摘要:

E D I T O R I A L Chemistry has of course never looked greener. But what about the future of the field we call Green Chemistry? We continue to hear encouraging news from the UK Scandinavia and other parts of Western Europe. There is also great chemistry being developed in some Eastern European laboratories. Innovation and greening of chemistry continue to proceed rapidly in both the United States and many Asian countries. Luckily these advances are not confined to the academic arena but are clearly being practiced by an increasing number of commercial organizations. So is there anything wrong with this picture? I would say "Yes". Green chemistry is so diverse that we often have trouble communicating amongst ourselves and often spend too much time arguing about what is really Green.These misunderstandings and arguments drain away our precious time for doing Green chemistry. When it comes to definitions of the field there are purists and there are revisionists; there are the dogmatic and the lackadaisical. When it comes to chemistry there are those who do it and those who talk about it those who set policy and fund grants and those who spend money generously provided by government and private funding agencies. All of these groups play vitally important roles in the health of the field. In the United States we have clearly seen of funding and regulatory agencies leading rather than following scientists into this new arena. I want to offer my personal take on what is Chemistry and what is Green and how to navigate the political waters that seem to have a few more sharks in them every year.I see societies benefiting greatly from industrial chemistry whether it is commodity chemistry fine chemistry or pharmaceutical chemistry. I also see a large number of “legacy chemical processes" that date back to be exciting early days when industrial chemistry was created largely in British German and Italian laboratories. These processes tend to generate large amounts of waste side products and undesirable or even toxic byproducts. Green Chemistry April 2002 G14 Green Chemistry Can we rally together or will we fragment into pieces? James K. Bashkin St. Louis MO USA In my view any chemical advance or engineering advance that significantly reduces the burden placed on the environment by current industrial processes is helping to clean up the DOI 10.1039/b202353a This journal is © The Royal Society of Chemistry 2002 environment by definition.Many of these advances may not be fully Green there may still be some waste generated there may still be lifecycle issues that have not fully been considered and there may still be unforeseen consequences that this new chemistry presents to the environment. We must be as vigilant as possible to avoid doing any greater harm while we attack the obvious problem processes with new vision. However if we see a new process that clearly eliminates millions of tons of waste a year I believe we should lend its a welcome ear and view it as a marvelous step in the right direction even if the chemistry is not yet perfect.I would like to see similar principles applied in the evaluation of academic work on the subject of Green chemistry. In many cases we will have to take small steps towards the ultimate greening of a particular chemical reaction. As long as these steps move the chemistry in the right direction I believe they should be heard by the community and collected in this journal. I can easily imagine and in fact have often witnessed catalytic cycles being put together by two different research groups each one of which has developed a beautiful new half reaction. I can also imagine a third research groups adapting such chemistry to one of the greener solvents now recognized by the community. The stepwise creation of Verdant Reactions will be just as valuable as the much rarer all-in-one instantly perfect replacement for a 50-year-old chemical process. I hope that in the upcoming Italian summer school Gordon Research Conference and other meeting places for those of us who practice preach and believe in Green chemistry we will see plenty of vigorous and even contentious debate on where we should focus our attention to bring about the greening of the environment and the Industry. But I also hope that the discussions and debates will leave room for the full spectrum of Green chemistry practitioners and will ultimately respect the various ways that each of us tries to impact industry academics and the environment.

ISSN:1463-9262    

DOI:10.1039/b202353a

出版商:RSC    

年代:2002

数据来源: RSC

摘要:

Rate the sustainability grade of your scientific work Achim Diehlmann† and Guenter Kreisel‡ of the Friedrich Schiller University in Jena Germany propose a new nomenclature for sustainablity in chemistry which aids appreciation of the different levels at which sustainability can be considered Introduction Sustainability is one of the outstanding objectives in chemistry. Therefore various research programs have been set up numerous conferences have been held and a high number of research papers have been published on this topic. The high quality of the published work on sustainability shows that the scientists involved are on the right track. Nevertheless many papers could be criticised because of their broad and diffuse interpretation of the term ‘sustainable’.To avoid misunderstanding to specify the proposition of scientific work and to prevent ambiguity of the term ‘sustainable’ we propose a nomenclature for sustainability in chemistry that could help return to the concept of sustainable development the importance it deserves. Sustainable development Sustainable development with its widely accepted principles is one of the important goals of the future. The Brundtland Report1 initially defined sustainable development as a development “to meet the needs of the present without compromising the ability of future generations to meet their own needs”. The development should bring about improvements in economical ecological and social conditions for present and future generations worldwide.Since the Brundtland Report and especially since the Rio Declaration of Sustainable Development,2 a great number of scientists have been working † Dipl.-Ing. (FH) Achim Diehlmann email achim.diehlmann@uni-jena.de Tel +49 3641 948434 Fax +49 3641 948402 Friedrich Schiller University of Jena Institute of Technical and Environmental Chemistry Lessingstr. 12 D - 07743 Jena Germany. ‡ Prof. Dr. Guenter Kreisel email guenter.kreisel@uni-jena.de Tel +49 3641 948430 Fax ++49 3641 948402 Friedrich Schiller University of Jena Institute of Technical and Environmental Chemistry Lessingstr. 12 D - 07743 Jena Germany. in different research areas of sustainability. In chemistry where the special area of Green Chemistry has been founded a lot of work has been done in this field of investigation.3,4 Almost all of the published work has attempted to minimise environmental burden e.g.by reducing waste production of synthesis by using less harmful substances or by saving energy. But are all of these improvements per se sustainable or green? The three areas of sustainability Sustainable development is based on an improvement of the three sustainable areas—economy ecology and sociology. Natural scientists and chemists in particular very often improve just one part of sustainability—the ecological side—because they are experts in this field. The other parts—the economical and social aspects—may also be enhanced by the ecological improvement or they may be negatively affected.Since these aspects were not the focus of research whether the improvement is economically and socially sustainable or not cannot be determined without further research investigation. This further research must be carried out by experts in economic and social sciences to give a balanced assessment of sustainability. If investigations in all three fields is not carried out a new chemical process with minor environmental impact is only sustainable in terms of ecology. To evaluate new processes in the three sustainable areas and to define and standardise the term ‘sustainable’ to avoid misuse and exaggeration we propose a nomenclature that indicates which part of sustainability of a process has been investigated and which part has not.We suggest using an ‘S’ to indicate sustainability and adding ‘econ’ ‘ecol’ and ‘soc’ to indicate which areas have been researched (Fig. 1). An example should illustrate the idea. Within a chemical synthesis a toxic solvent is being substituted by a less toxic or nontoxic solvent. Ostensibly the new synthesis is more sustainable than the former and can be represented by S econ ecol soc. However if the new solvent is more expensive than the one it substitutes the process is less sustainable in terms of the economical sustainability. The sustainability classification would therefore become S econ ecol. If it is further assumed that the producer of the toxic solvent has to dismiss a worker because G15 Green Chemistry April 2002 DOI 10.1039/b202354g Fig 1 Indicator of sustainable areas.This journal is © The Royal Society of Chemistry 2002 NEWS & V I E W S NEWS & V I E W S he cannot find customers for the solvent the process now becomes only S ecol because of the lost working place. The term S econ ecol soc therefore is only valid if all three parts of sustainability have been improved. The holistic view of sustainability A further and often subconsciously neglected claim of sustainable development is an improvement not only in small process steps but over the whole life cycle. The ignoring of upstream and downstream products and processes could be a matter of insufficient data or a lack of awareness.It is often essential to focus an investigation within the narrow borders of a process. However if the view is limited to a process one must be aware of potential problems that could arise in a holistic context. This awareness is often problematical since scientists are trained to solve a specific problem without taking upstream and downstream processes into account. Here further education seems to be necessary. It is essential when publishing results always to state whether sustainability has been taken into account in a process or a ‘cradle-to-grave’ view. We therefore suggest indicating the view with a ‘H’ for the holistic approach ‘HS’ and a ‘P’ for a process-oriented approach ‘PS’ (Fig. 2). The above example indicates the importance of this approach.• were more expensive than the old process because it needed more production steps • generated a higher amount of waste that could also be toxic Green Chemistry April 2002 G16 then to state that the new process is more sustainable would be correct in a process view but incorrect in a holistic view. Using the proposed nomenclature would prevent misunderstanding and encourage scientists to examine and hopefully improve processes. Coming back to the Brundtland Report and the Rio Declaration there is another reason for setting up a standardised nomenclature. The Report and the Declaration focus on human needs. But these needs are beside the necessities like access to sufficient fresh water and nutrition based on geographical differences.These differences derive from climatic variations from religious constraints and from cultural differences. Fig. 3 Indicator of the sustainable scale. • required more energy to produce The scale of sustainable development If use of the new less toxic solvent from the previous example glob Fig. 2 Indicator of the investigation view. This journal is © The Royal Society of Chemistry 2002 The needs of a Mediterranean citizen for instance are essentially different from the needs of a Scandinavian citizen. Focusing on environmental issues there are questions of scale. An accident with toxic chemicals for example might harm the environment locally and perhaps regionally if the amount of toxic substance is great enough but it is not a global threat.A contribution to the greenhouse effect however can affect the whole world and is therefore a global problem. Sustainability therefore has a local regional and global character. Developments that lead to local improvements do not necessarily have an effect on a regional and global scale whereas a global scale improvement brings benefits to everyone. We recommend extending the proposed nomenclature to include the scale on which the invention is sustainable i.e. on a local (Sloc) regional (Sreg) or global scale (Sglob) (Fig. 3). Using this nomenclature will help avoid misunderstanding since it is clear what has been done and what still has to be done. Furthermore the nomenclature will help to prevent inappropriate comparisons e.g.local ecological sustainability and social sustainability. To demonstrate the advantage of the suggested nomenclature we refer to our example a third time. Assume that the producer of the toxic solvent has to dismiss a worker because he cannot find a new customer for the solvent. The process may now still be Secol. soc. since the manufacturer of the new solvent may hire a worker but on a local scale it may also be onlySecol. loc because of the lost working place. Fig. 4 shows the complete structure of the proposed nomenclature. The potential of biocatalysis to provide chiral products from achiral raw materials is enormous. However one drawback which is often encountered is the requirement for a cofactor and its need to be regenerated rapidly and efficiently.Richard Fish and Christine Lo of the University of California at Berkeley USA have demonstrated that NADH mimics can be successfully utilised for Fig. 4 The complete structure of the nomenclature. Conclusion 4 P. T. Anastas and J. C. Warner. Green Chemistry 2000 Oxford University Press Oxford UK. The proposed nomenclature system is a first attempt to handle the problems of communicating sustainable chemistry progress. It is an open system and may be Highlights Duncan Macquarrie reviews the recent literature on green chemistry Biocatalysis Enantioselective epoxidation Ionic liquids This journal is © The Royal Society of Chemistry 2002 NEWS & V I E W S widened if necessary.As shown the suggested nomenclature of sustainability is useful to specify the proposition of scientific work in three major areas. Standardised nomenclature further helps this purpose in horse liver alcohol dehydrogenase (HLADH)-catalysed reduction of ketones (Angew. Chem. Int. Ed. 2002 41 478). They used a rhodium hydride catalytic cycle to reduce nicotinamide derivatives which then functioned with HLADH to reduce a series of ketones to alcohols in high yield and enantioselectivity. The enantioselective epoxidation of a,ß-unsaturated ketones is a key step in the synthesis of a range of important molecules. Waldemar Adam and co-workers at the University of to prevent ambiguity of the term ‘sustainable’ and to give it back the importance that it deserves.We would like to thank Prof. Dr. B. Jastorff for his suggestions for improvement. Further we would like to thank Prof. Dr. B. Koenig spokesman for the project group of the ‘New organic chemistry practical for the new millennium’ project for the helpful commentaries. References 1 G. Brundtland Our Common Future 1987 Oxford University Press Oxford UK. 2 Report of the United Nations Conference on Environment and Development United Nations 1992 Rio de Janeiro. http://www.un.org/esa/sustdev/ 3 C. A. Eckert D. Bush J. S. Brown C. L. Liotta Tuning Solvents for Sustainable Technology. In Industrial & Engineering Chemistry Research 2000 39 4615–4621 Würzburg Germany have now shown that optically active hydroperoxides can be used to form these products in high yield and good enantioselectivity (Eur.J. Org. Chem. 2002 630). What is particularly fascinating is that the choice of base catalyst is critical. With KOH as base the reaction produces one enantiomer the use of diazabicycloundecane (DBU) leads to the other isomer. These differences are accounted for in terms of different coordination of the species involved in each of the two cases. Ionic liquids are attracting significant attention as potential replacements for organic solvents. One such type of ionic liquid is the N-alkyl,NA-methylimidazolium tetrachloroaluminate which also functions as an acid catalyst.Raj Varma and Vasudavan Namboodiri Green Chemistry April 2002 G17 NEWS & V I E W S of the US Environmental Protection Agency have now described a novel microwave-assisted route to these liquids which reduces reaction time and energy use significantly (Chem. Commun. 2002 342) and also the use of traces of these compounds for the tetrahydropyranylation of alcohols again under microwave irradiation. Both reactions proceed in excellent yield. The behaviour of various metal catalysts for the Michael reaction in ionic liquids has thrown up some very interesting results. Cosimo Nobile and colleagues at the University of Bari Italy have investigated the addition of pentane-2,4-dione with methyl vinyl ketone in butyl methylimidazolium tetrafluoroborate using three different metal based catalysts (Chem.Commun. 2002 434). They found that Ni(acac) catalysts dramatically enhanced the rate of reaction when used in ionic liquids but were much poorer in dioxane and also were slower in the absence of solvent. Excellent yields were obtained in the ionic liquid and the catalytic solution could be reused several times upon direct distillation of the reaction product and re-charging of fresh reagents. Conversely when either Yb(iii) or Fe(iii) catalysts were used the reaction was much slower in ionic liquids than neat but the selectivity was much higher than the 50–60% found neat. (The neat reactions proceeded much further than those in ionic liquids in these two cases something which may explain the changes in selectivity).Osaka Japan have now demonstrated a one-step catalytic method for this reaction involving the oxidative addition of malonate to alkenes using a Mn(ii) / Co(ii) / O2 system in acetic acid solvent (J. Org. Chem. 2002 67 970). Yields are very good and selectivity is also high. Other C-acids can be used and alkynes also show some reactivity. Supercritical CO2 The use of supercritical CO2 as reaction medium has been used by Nils Theyssen and Walter Leitner of the Max-Planck Institute in Mülheim an der Ruhr Germany for the selective oxidation of cyclooctane to cyclooctanone using oxygen and acetaldehyde as sacrificial reductant (Chem. Commun.2002 410). They found that conversions of almost 40% were possible with the production of cyclohexanone as major product along with smaller amounts of the alcohol and the 1,4-dione being also formed the latter providing supporting evidence for a radical pathway. Malonates The mono-functionalisation of malonates at the CH2 group is a very useful strategy to build up functional building blocks. Such reactions can be achieved via the Knoevenagel reaction and subsequent hydrogenation but can have some drawbacks. Yasutaka Ishii and co-workers at Kansai University in Green Chemistry April 2002 G18 This journal is © The Royal Society of Chemistry 2002 Bismuth catalysts A short review has appeared in Synlett where Cristophe Le Roux and Jacques Dubac of the Universite Paul Sabatier in Toulouse France discuss catalytic aspects of bismuth salts (Synlett 2002 181).Bismuth is the least toxic of the heavy metals and its application in a range of acid catalysed reactions is discussed with mechanistic insights being derived about the actual catalytic species. For example bismuth triflate serves as an effective catalyst for the difficult acylation of unactivated aromatics such as benzene toluene and halobenzenes giving high yields of acylated product in reasonable times with either acid chlorides or anhydrides. Sulfonylations are also readily achieved with a few percent catalyst. Transesterification Transesterification of esters is a reaction type of great significance in a variety of areas.Solid acids are well suited as catalysts for this transformation since they can be easily removed without the addition of water which can cause hydrolysis. Vitor Ferreira and colleagues from the Universidada Federal Fluminense in Niteroi Brazil have found that some clays are excellent catalysts for the transesterification of ketoesters and carbohydrates (Tetrahedron Lett. 2002 43 1165). They found that smectite vermiculite and atapulgite all catalysed these reactions in good to excellent yields. More traditional acid clays such as K10 were relatively inactive. Aromatic aldehydes ? esters The direct conversion of aromatic aldehydes to esters has been described by a group led by Subhash Chavan of the National chemical Laboratory in Pune India (Synlett 2002 267).They have utilised an oxidative process involving the aldehyde methanol hydrogen peroxide and the titanium-silicate zeolite Process technology A fascinating special feature section in Organic Process Research and Development (Org. Proc. Res. Dev. 2001 5 612–664) has been published focussing on Intensive Processing and Continuous Processing in industrial production of fine chemicals. A series of articles from industrialists discuss the NEWS & V I E W S TS-1 as catalyst. Yields range from 65–99% under reflux in methanol for a few hours. Aliphatic aldehydes are also converted to esters but in lower yields. The authors suggest the mechanism shown below as a plausible explanation for the process.advantages available from innovative reactor design and how this can be used to enhance reaction rates conversions and reduce the potential for hazardous incidents. Several examples are shown utilising a range of techniques and reactor types featuring miniaturisation or intensive mixing features. Such considerations of process technology are an integral part of designing a safe energy and chemical-efficient process. Sustainable development A review has been published by Jürgen Metzger and colleagues from the University of Oldenburg Germany to coincide with the World Summit on sustainable development in Johannesburg South Africa (Angew. Chem. Int. Ed. 2002 41 414). This overview describes the societal context of chemistry within sustainable development and sets out the challenges for chemistry in contributing to this area.Key challenges are seen as the development of cleaner processes especially for large volume common intermediates and successes in the production of propylene oxide and adipic acid are described. A further area of importance is the development of novel separation methods which underpin the majority of processes and are critical to a genuinely clean process (as opposed to a clean reaction). Green Chemistry April 2002 G19 This journal is © The Royal Society of Chemistry 2002 NEWS & V I E W S The importance of improving regulation in encouraging the development and adoption of greener chemical processes and products Michael Warhurst,† Safer Chemicals Campaigner at Friends of the Earth in London UK argues that in addition to the Principles of Green Chemistry there is a need for the development of a regulatory system that encourages the application of green chemistry Introduction The editorial in the first edition of Green Chemistry1 included a definition of Green Chemistry which had been originally proposed by Paul Anastas and John Warner "Green Chemistry is the utilisation of a set of principles that reduces or eliminates the use or generation of hazardous substances in the design manufacture and application of chemical products" In this paper I will argue that it is vital that this 'set of principles' includes the development of a regulatory system that encourages the application of greener chemistry as in many cases it is only through regulation that we will be able to 'reduce or eliminate the use or generation of hazardous substances'.I will also argue that it is the responsibility of the green chemistry community to get involved in this regulatory debate rather than leaving it to the usual suspects—the chemical industry the regulators and the non-governmental organisations such as Friends of the Earth. Green Chemistry will not contribute to sustainability unless it is implemented. The current systems for regulating the production and use of chemicals do not encourage the development of greener products and processes and in many cases actually do the opposite.An important reason for examining the role of regulation on greener chemistry at this time is that the European Union is currently reviewing † From 2/4/02 Senior EU Toxics Campaigner WWF Brussels Belgium. Green Chemistry April 2002 G20 this legislation. The signs are that this review will result in substantial changes in the legislation which could improve the drivers for greener chemistry. The role of regulation in the adoption of green chemistry There are three main ways in which regulation impacts on the adoption of green chemistry influencing prices (or costs); restricting options and influencing demand. I will briefly outline how these impacts occur. Influencing prices Regulation has a huge impact on the prices or costs attached to using chemicals.Such cost may in some cases be deliberately intended to internalise some of the external impacts caused by the use of a product into the price of the product. Impacts occur throughout the lifecycle of a material for example • Raw materials. The cost of raw materials can be very dependent on regulation for example through legal restrictions on extraction (e.g. planning controls) or through environmental taxation (e.g. carbon tax). • Regulation of production processes. The price of a more hazardous chemical may be more expensive because of additional production costs for example due to pollution control regulations. • Costs of using a material.More hazardous materials are likely to cost more to handle due to Health and Safety regulations. • Disposal costs. Regulations define permissible disposal routes and generally mean that the most hazardous material will cost the most to dispose of. Regulation will define whether the cheapest routes of disposal (e.g. discharge into the local river) are available. Restricting options Regulations that ban or heavily restrict the use of certain chemicals or processes will clearly impact both on the economics of these chemicals and processes and on the market for substitutes for example • Phase out or restriction on specific chemicals. Once it is known that a chemical is to be phased out or heavily restricted the development (or improvement) of substitutes becomes essential.In addition it is quite possible for these substitutes to be more expensive since it is not the market that is controlling the decline in use of the restricted chemical. • Phase out or restrictions on specific processes. Processes may also be affected by phase out or restriction for example the use of mercury cells in production of chlorine in the EU. Again this provides huge practical and economic incentives for the development of greener alternatives. Influencing demand ‘Softer’ regulatory approaches can also influence demand for a product or process and its alternatives by either encouraging or discouraging its use This journal is © The Royal Society of Chemistry 2002 • Discouraging the use of a product.Several methods of discouraging the use of a product have already been mentioned for example through increasing its price through environmental taxation or by announcing that it will shortly be banned. However there are also other methods available for example adding it to a list of less desirable chemicals (e.g. the Swedish ‘Observation List’ below) or by excluding its use in the criteria for products with an ecolabel. • Encouraging the use of a product. The use of a greener product can be encouraged through reductions in taxation (as happened initially with unleaded petrol) or by a range of ‘promotional’ activities. For example a Government (or other institution) could assist companies moving to greener products by providing advice to companies on what alternatives are available and by publicising the existence of these alternatives.The impact of regulation The above outline has flagged up a large number of relevant regulations which have a direct impact on the market for greener chemicals. Looking purely at the European situation important regulations include • chemical substance related legislation e.g. Marketing and Use Classification and Labelling New and Existing Substances (see below) • factory emissions legislation e.g. Integrated Pollution Prevention and Control Directive • waste disposal legislation e.g. Landfill Directive • factory safety legislation e.g. Control of Major Accident Hazards Directive • product-related legislation e.g.Ecolabelling If there was no regulation at all there would be minimal financial pressure for the adoption of greener chemistry. With no regulation it would be most cost effective to discharge most of a company's waste into the local river—as happened during the 19th century. Given therefore that regulation is essential for the adoption of greener chemistry it is surprising how little research and debate there is within the Green Chemistry community on what is the best regulation. What about the voluntary approach? One argument particularly from industry is that a combination of market pressures NEWS & V I E W S and voluntary action will be sufficient to ensure the adoption of greener chemistry.As discussed above many of the price signals that affect the profitability of greener chemistry in fact come from regulations in any case so these ‘market’ pressures are in reality hugely influenced by regulation. There is little evidence that pure ‘voluntary’ action is effective. Companies may act before regulation forces them to but this is primarily a response to the changing market place as the regulatory deadlines approach. Companies may also respond to public pressure regarding a particular chemical or to concerns that such pressure may come in the future. Even with more elaborate environmental management systems such as ISO 14001 and EMAS there is currently no clear evidence of a link with good environmental performance.2 The predominant focuses of the industry are on whether a process or product is legal and whether it is profitable (i.e.whether it adds to shareholder value). It is however true that a few companies take a longer term view of profitability and shareholder value which can assist in their approach to sustainability. It is worth noting that in some countries (e.g. The Netherlands) voluntary agreements are actually legally binding contracts. This increases their chances of success as they are in effect another form of regulation. The chemical industry makes much of voluntary programmes such as ‘Responsible Care’ and ‘Product Stewardship’,3 and has various impressive sounding statistics to back them up.Yet these claims ignore changes that have occurred in the regulatory environment. For example there have been many changes in the UK regulations for factory emissions in the past decade including the introduction of ‘Best Available Technology Not Exceeding Excessive Cost’ in Integrated Pollution Control the creation of the Environment Agency and now the EU-wide Integrated Pollution Prevention and Control system introducing ‘Best Available Technology (BAT)’ with BAT reference documents being created to cover the whole of Europe. Yet industry statistics on emission reductions due to ‘Responsible Care’ ignore regulatory changes. A particular issue with sustainability and the use of hazardous chemicals is the fact that one ‘worst of sector’ company can cause huge damage through continuing to market and produce undesirable chemicals.A chemical banned in the EU (e.g. tetraethyllead) can still be manufactured in the EU for export to the developing world (this is still the case with tetraethyllead). Is the current EU regulatory system contributing to greener chemistry? Most aspects of the regulation of the production and use of chemicals in Europe are regulated at an EU level with individual Member States having only limited flexibility to impose their own regulation. This is not the place for a detailed description of the regulatory process (a more detailed summary is available in chapter 4 of the ‘Crisis in Chemicals’ report4) but the regulations relating to marketing and use of ‘Industrial Chemicals’ (not pesticides biocides or pharmaceuticals which all have their own systems) can be summarised as consisting of four elements • Classification and labelling.A process whereby classifications are agreed for substances based on the safety data which is available. Classifications including for example toxic to reproduction are agreed and then may affect how the substance is labelled when it is sold and may also impact upon what it can be used for. • Marketing and use. A reactive process in which concerns over substances can be investigated and decisions on restrictions on the use of that substance can be agreed if there is sufficient information is available on the harm that the chemical can cause.• New chemicals. The beginnings of a move to a more pro-active regulatory system the New Chemicals system requires that all chemicals introduced to the market after 1981 must have a set of safety data available. A new chemical is any chemical that is not included on the European Inventory of Existing Commercial Chemical Substances (EINECS) described below. • Existing chemicals. Existing chemicals are those that were claimed by industry to have been on the EU market at any point between 1971 and 1981. Industry submitted the names of these substances to the European Inventory of Existing Commercial Chemical Substances (EINECS) which meant that these substances did not have to go through the new chemicals process.The list contains 100,106 substances though it is estimated by that there are in reality around 30,000 existing substances on the market at more than Green Chemistry April 2002 G21 This journal is © The Royal Society of Chemistry 2002 The data problem NEWS & V I E W S 1 tonne per annum in the EU.5 Although the Existing Chemicals process does not oblige companies to generate new safety data on their chemicals they are supposed to have submitted what data they had to the European Chemical Bureau (ECB the body that administers EU chemicals regulation). This data is then supposed to be used to decide which chemicals are a priority for further investigation culminating with a complex risk assessment and risk management process.Problems with the current regulatory system and how they impact on the development of greener chemistry The current EU system is now widely acknowledged to be failing. This failure has in recent years led to increasing discussion on how to improve things culminating in the current debate on the nature of a new regulatory system. I will focus on five deficiencies which are particularly relevant to the adoption of greener chemistry • the lack of any obligation to deliver safety data on Existing Chemicals in contrast to New Chemicals; • the high burden of evidence that is required to remove a chemical from the market; • the lack of precautionary action against chemicals that accumulate in our bodies or the environment; • the lack of an obligation on industry to use the safest available chemicals in their products; • the considerable secrecy about what chemicals are used in products and the lack of accessible safety information for downstream users and the public.The lack of any obligation on industry to generate the same quality and quantity of safety data on Existing Chemicals has created a huge data vacuum. A survey by the European Chemicals Bureau of their database found that only 14% of the EU high production volume chemicals—those 2593 chemicals produced and imported at over 1000 tonnes/year—have a full 'base set' of safety data publicly available. Jan Hammer of the Swedish National Chemicals Inspectorate summed up the problem at a conference in December 1999 “If it is not possible to perform a hazard assessment for 95% of the substances on the market then in reality these substances are not covered by the current legislation.This is a major Green Chemistry April 2002 problem in a nutshell most substances on the market are in reality not covered by the current legislation.” 6 However safety data must be generated for ‘New Chemicals’. As any Existing Chemical on the EINECS list can be used without safety data such chemicals are in effect subsidised. This therefore discourages the development of greener newer chemicals. The evidence problem The regulatory system puts many barriers in the way of taking action on chemicals for which concerns have been raised.This is partly due to the lack of safety data available problems in determining the uses of many chemicals and a slow and complex regulatory process. However a major contributor is the high burden of evidence that is required before restrictions can be put in place. This high burden of evidence has led to inaction on many chemicals of concern notably endocrine disrupting chemicals (EDCs) even where there is substantial evidence of concern. Such delays are in contrast to pressures for precautionary action coming from scientific bodies such as the Royal Society in the UK whose report in June 20007 stated “Despite the uncertainty it is prudent to minimise exposure of humans especially pregnant women to EDCs”.A lack of regulatory action on chemicals of concern reduces the pressure for development and use of greener alternatives. Little action on persistent or bioaccumulative chemicals A key element of many approaches to sustainability is the belief that we should not be causing any build up of chemicals in the environment above background levels. Many would also believe that it is unacceptable to be contaminating our bodies—and those of wildlife—with man-made chemicals whether we currently know them to be toxic or not. But we are—a WWF review in 1999 found that “several hundred man-made chemicals have been found as contaminants in human body fat and many of these can be passed on to babies at a particularly sensitive stage in their development via the placenta and during lactation”.8 The continued routine use of persistent and/or bioaccumulative chemicals is particularly surprising given previous experience (and continuing problems) with chemicals such as polychlorinated biphenyls and CFCs.9 G22 This journal is © The Royal Society of Chemistry 2002 However the current regulatory system with its emphasis on proving that harm will be caused before taking action is not able to deal with the problems caused by chemicals that are persistent or can bioaccumulate.It is almost impossible for such chemicals to be controlled in the current system so their use continues. Lack of an obligation to use the safest available chemicals The current regulatory system does not put pressure on industry to use the safest (or greenest) chemicals available; companies will more commonly use the cheapest.Some sort of obligation to use the safest available chemical will have a huge impact on the economics of research and development of safer alternatives. Currently there is a considerable commercial incentive for companies to continue manufacturing and marketing less safe but cheaper chemicals even if they themselves are marketing the safer alternative. One example of this is the production of alkylphenol ethoxylate surfactants. Despite the manufacture of alternative surfactants (and the gradual tightening of EU regulations on these chemicals10) the industry continues to manufacture these poorly-degradable hormone disrupting chemicals.At a meeting of the UK Government's Stakeholder Forum on Chemicals in December 2001 it was argued by one company representative that that if their customers didn’t get alkylphenols from them they would get them from someone else. This statement also demonstrates the importance of regulatory restrictions on problem chemicals otherwise less responsible companies will always be able to use this argument. Secrecy The current regulations do not oblige producers to inform downstream users or the public of what is in the products they are using. This can make it extremely difficult for a downstream user or retailer to find out whether they are using chemicals that they may be concerned about and whether other products are available that do not use this chemical.A common problem with the EU risk assessment process is that insufficient information is available on the actual uses of a chemical of concern making it difficult for risks to be assessed. A more open system with information flowing freely up and down the supply chain would enable the uses of chemicals of concern to be clearly visible assisting A new approach Sweden one of the first countries to ban PCBs has been implementing more precautionary regulation of chemicals for many years and has recently moved to extend this regulation in a new chemicals bill.11 Their regulatory system includes both ‘soft’ and ‘hard’ regulation • Soft regulation.The Government publishes an 'Observation List' of less desirable chemicals based on clear criteria.12 This list does not result in legal restriction but industry is encouraged to substitute listed chemicals by less hazardous alternatives. This reduces the profitability of the less desirable chemicals. • Hard regulation. The new chemicals bill calls for new products for sale to general consumers to be "as free as possible" from substances which are carcinogenic mutagenic or toxic to reproduction (frequently abbreviated to CMR) by 2007. It also calls for a ban by 2005 on new organic bioaccumulative and persistent substances; by 2010 on other organic substances which are "very persistent and very bioaccumulative,”; and by 2015 on other organic persistent and bioaccumulative substances.In addition it requires safety data to be provided for all chemicals in use by 2010 and that all products containing hazardous substances are labelled by this date. A fundamental review of EU chemicals regulations is underway. A key part of the debate is the contrast between approaches similar to the Swedish Government’s and more traditional approaches which focus on proving harm from a chemical before regulating it. After a number of stakeholder meetings and tough internal debate the Commission published a White Paper on a new chemicals policy in February in the development and promotion of greener alternatives. Chemicals regulation in Europe is now under review with Sweden leading the way with its own proposals.The Swedish approach Current proposals for a new EU regulatory system The current proposal for a new regulatory system includes the following key points The chemical industry’s approach to the policy review Sweden has stated that it wishes to see its approach to chemicals regulation reflected in the new EU system. The debate on a new EU system The view of Environment and Consumer NGOs • A full right to know including what chemicals are present in products. This journal is © The Royal Society of Chemistry 2002 NEWS & V I E W S 2001.5 This White Paper has been discussed by the Member States with Environment Council (made up of EU Environment Ministers) agreeing conclusions on it in June 2001.13 It was then discussed by the European Parliament who produced a report on it in November 2001.14 • that all chemicals produced at > 1 tonne/year should have safety data provided by 2012.In addition it increases the thresholds for testing requirement for new chemicals thus making it cheaper for industry to introduce new products by reducing the testing required for lower tonnages • the creation of an 'Authorisation' scheme for chemicals of high concern where use of the chemicals will be phased out except for specific authorised uses. The definition of 'high concern' is currently under dispute. The White Paper proposed that this should include carcinogens mutagens and reproductive toxins (CMR) and chemicals which meet the criteria for persistent organic pollutants as defined in the UNEP POPs treaty.It also proposed adding persitent bioaccumulative and toxic chemicals (PBT) and very persistent very bioaccumulative chemicals (vPvB) once criteria have been agreed. Environment Council supported extension to PBT and vPvB and also proposed addition of proven endocrine disrupters and sensitisers. In contrast the Parliament—in a very close vote—backed limiting authorisation just to CMRs and POPs • a new centralised 'Chemicals Agency' • more responsibility to industry and increased flow of information up and down the supply chain Environment and Consumer NGOs have been collaborating on a common position on the chemicals review including the agreement in December 1999 of the 'Copenhagen Charter' a summary of their demands We demand from the EU review of chemicals policy • A deadline by which all chemicals on the market must have had their safety independently assessed.All uses of a chemical should be approved and should be demonstrated to be safe beyond reasonable doubt. • A phase out of persistent or bioaccumulative chemicals. • A requirement to substitute less safe chemicals with safer alternatives. • A commitment to stop all releases to the environment of hazardous substances by 2020. • A more detailed discussion of how these principles could be applied to the EU regulatory system is given in the Crisis in Chemicals report which also examines the impacts of the biomedical revolution on chemicals regulation.4 The chemical industry through their European lobbying organisation CEFIC is heavily involved in the chemicals policy review.Some of the positions that they are promoting which are particularly relevant to the promotion of green chemistry include • opposition to the authorisation process. Initially CEFIC spokespeople were totally opposed to the authorisation approach later they moved to a policy of only accepting a very limited process covering only CMRs and UNEP POPs only if other legislation did not already apply to the chemicals concerned and a risk assessment proved that there was a risk15 • opposition to taking action on vPvB or PBT chemicals except if they are shown to be a proven risk in risk assessment.CEFIC do not support any action on chemicals unless their known toxicity is sufficient to be a proven risk; • opposition to observation lists and general obligations to use the safest chemicals. In addition CEFIC and their its sector groups frequently lobby against restrictions on individual chemicals as they are passing through the current EU risk assessment process for example during the debate on the brominated flame retardant 'penta' which is increasing in concentration in breast milk.16 US chemical manufacturers also frequently put pressure on the EU process for example arguing against controls on alkylphenols.17 Green Chemistry April 2002 G23 NEWS & V I E W S The process from here The Commission has set up a number of technical working groups to examine various aspects of the new legislation.It is hoped that new draft legislation will be published in Summer 2002 and it will then be debated in both Environment Council and the European Parliament—both of which must agree the final legislation. Therefore the policy approach taken by the Governments of all the EU member states will be crucial to the outcome of the Environment Council debate whilst the European Parliament's conclusions will be determined by the policy position taken by the MEPs and their party groups. It will probably take around two years to complete the process which is likely to include two readings in the parliament and finally the 'Conciliation' process in which Council and the Parliament must reach a compromise position.Regulation has a major impact on the economics and application of Green Chemistry. A large part of this regulation is now under review in Europe providing an opportunity to improve these regulatory drivers. Therefore there is an opportunity for a debate on what regulatory methods best drive greener chemistry. Key questions include • how regulations can be designed to encourage—and force—positive innovation? • what is the best method of encouraging or forcing substitution? What is the potential for Swedish-style observation lists and when might it be necessary to use more complex 'Comparative Assessment' methodologies? • what methods are available for rapid decision making on whether a product or process is overall greener more sustainable and safer than an alternative? Those 'Green Chemists' who are interested in the subject might also find it beneficial to learn more about the issue from the numerous reports and other documents available (e.g.ref. 18 and ref. 19). In addition they could discuss the issue with their political representatives and Governments. For example it is unfortunate that the UK Government's Department for Trade and Industry has tended to lobby against tighter regulation Green Chemistry April 2002 Green Chemistry aims to minimise environmental impacts from the production and use of chemicals.A crucial part of this minimisation of impact is the presence of regulations that discourage or prevent the use of more hazardous chemicals and which provide incentives for the use of greener alternatives. Without technology-forcing regulation the status quo is frequently easier and cheaper which is crucial since profitability and legality will remain the main drivers for the chemical industry (and most if not all other industries). Most of the major environmental improvements that have occurred have been created by new regulations not by voluntary or market mechanisms. Examples include the control of urban smog through clean air acts (banning the use of various fuels) the phase out of lead in petrol in the developed world (through a legal phase out combined with financial incentives) and the role of the Montreal protocol in reducing and eventually (in the future) stopping the destruction of the ozone layer (through legally binding phase out of ozone depleting chemicals).The current EU review of chemicals regulation provides an opportunity to promote the use of greener chemicals in Europe. In addition the results of this European review will have an impact on the development of a global approach to chemicals control a process which is now underway within the United Nations Environment Programme. 1 J. Clark 'Editorial' Green Chemistry 1999 1 G1–G2. 2 ENDS 'Agency cools on greater role for management systems under IPPC' ENDS Report 2001 323 12–13.2001 Commission of the European Communities Brussels Belgium. http:/ /www.europa.eu.int/ comm/environment/ chemicals/whitepaper.htm 6 EU Chemicals Regulators Future G24 of chemicals use 20 rather than promoting the role of regulation in encouraging innovation. Conclusions The role of green chemistry research in the regulatory debate National Chemicals Inspectorate (KEMI). http://www.kemi.se/publikationer/obs_ eng/defaulte.htm 15 CEFIC Thought Starter on REACH. An References initial proposal for translating the REACH system into practice 2001 CEFIC Brussels. 16 ENDS 'Industry admits flame retardant pollution resists phase-out' ENDS Report 1999 298 13–14. 3 CIA Product Stewardship 1992 Chemical Industries Association London.17 ENDS 'US manufacturers attack NPE phase-out proposals' ENDS Report 1999 298 45. 18 FoE Safer Chemicals Campaign 4 A. M. Warhurst Crisis in Chemicals The threat posed by the 'Biomedical Revolution' to the profits liabilities and regulation of industries making and using resources for experts 2002 Friends of the Earth. http://www.foe.co.uk/ campaigns/safer_chemicals/resource/ experts.html 19 Euractiv Chemicals links dossier 2002 chemicals 2000 Friends of the Earth London UK. http://www.foe.co.uk/ resource/reports/crisis_chemicals.pdf 5 European Commission White Paper Strategy for a future Chemicals Policy European Chemicals Policy Report This journal is © The Royal Society of Chemistry 2002 Brainstorming session 16-17 December 1999 1999 Ministry of Housing Spatial Planning and the Environment The Netherlands. http:// www.vhcp.nl/ actualiteiten/reportbrainstorm.pdf 7 The Royal Society Endocrine disrupting chemicals (EDCs) 2000 The Royal Society London UK. http:/ /www.royalsoc.ac.uk/ templates/ statements/StatementDetails. cfm?statementid = 111 8 G. Lyons Toxic Trespass 1999 World Wide Fund for Nature Godalming UK. http:// www.panda.org/toxics/downloads/ chemical_trespass.doc 9 EEA Late lessons from early warnings the precautionary principle 1896-2000 2001 European Environment Agency Copenhagen Denmark. http:/ /reports.eea.eu.int/ environmental_issue_ report_2001_22/en 10 ENDS 'Risk reduction strategy but still no legislation on nonylphenols' ENDS Report 2001 323 52. 11 Swedish Environment Ministry Chemicals strategy for a non-toxic environment (Press Release) 2nd February 2001 Swedish Environment Ministry. http://www.regeringen.se/ galactica/service = irnews/owner = sys/ action = obj_show?c_obj_id = 37833 12 KEMI Observation List 1998 Swedish 13 Environment Council Strategy for a future chemicals policy COUNCIL CONCLUSIONS 2001 Environment Council Brussels Belgium. http:/ /europa.eu.int/comm/enterprise/chemicals/ chempol/whitepaper/councconcl.htm 14 European Parliament European Parliament resolution on the Commission White Paper on Strategy for a future Chemicals Policy (COM(2001) 88 - C5- 0258/2001 - 2001/2118(COS)) 2001 European Parliament Brussels. (Final text not yet on-line will be at www.europarl.eu.int) www.euractiv.com Brussels Belgium. http://www.euractiv.com/cgi-bin/ cgint.exe/ 99060-965?1100 = 5&714&1015 = 9&1014 = ld_chem&-TT = ENCHLD 20 ENDS 'DTI draws teeth from plans to reform UK chemicals policy' ENDS Report 1998 282 18–20.

ISSN:1463-9262    

DOI:10.1039/b202354g

出版商:RSC    

年代:2002

数据来源: RSC

摘要:

Ionic liquids This journal is © The Royal Society of Chemistry 2002 Professor Kenneth Seddon from Queen’s University Belfast introduces this special issue on ionic liquids Figure 1. The rise in publications concerning ionic liquids as a function of time as determined using SciFinder. The more observant of our readers will have noticed that this issue of Green Chemistry contains rather more papers concerning ionic liquids than is normal. Indeed there are more papers on this subject in this one issue than were published anywhere in 1988. Let me make it quite clear then that ionic liquids are not dominating the field of green chemistry! As the most cited paper in the first years of Green Chemistry was about ionic liquids an Editorial Board decision was taken to have a Special Issue devoted primarily to ionic liquids.As the appointed Guest Editor I invited papers from key researchers in the field for inclusion. However although papers were invited it should be clear that they underwent the normal full and rigorous refereeing and editorial process to which all RSC papers are subjected (after all this is a society not a commercial journal!). For my part I was honoured to be asked to do this and it was an extremely pleasurable experience—like organising a conference of world experts without the logistics! I believe that the papers included here ranging from organic synthesis to nuclear chemistry from catalysis to atomistic simulation from archival history to physical properties represent an exciting cross-section of the research being carried out both in industry and academia at the moment.They illustrate elegantly the breadth and diversity of ionic liquids research their green nature the international dimension and their potential for industrial application. I defy anyone who has an interest in chemistry whatever their field to read the papers in this issue and fail to be excited. Figure 1 illustrates the rise in publications concerning ionic liquids over the past few decades (and these are just the papers using the term “ionic liquid”). It will not be long before we are approaching 500 papers per year. A similar trend is found in the patent literature. There is little doubt that this phenomenal interest will continue.But is this good news? The simplistic but nevertheless correct answer is “yes”; if ionic liquids are to impact the field of green chemistry then we need to know much more about them experimentally and theoretically than we do now. Ionic liquids are the least developed of the viable green solvents; our ability to predict results and engineer processes is limited by the sparsity of extant data (especially physical thermodynamic kinetic and engineering data). We are only just starting to climb the ‘S’ curve of knowledge whereas heterogeneous catalysts are approaching the plateau. So this burgeoning of interest with the concomitant rise in published observations and data is to be welcomed without it ionic liquids will become a transient phenomenon an interesting academic footnote in the chemical archive.However everything has a price. With increasing activity comes the inevitable increasing “garbage” factor. In recent years we have seen papers reporting physical data on ionic liquids that were demonstrably impure liquids reported as solids and solids reported as liquids because of the impurity level communications “rediscovering” and publishing work (without citation) already published in the patent literature the synthesis of water-sensitive ionic liquids under conditions that inevitably result in hydrolysis and academically weak publications appearing in commercial journals with lax refereeing standards. On the positive side individual reactions such as the Heck reaction and the Diels–Alder reaction are being studied by a number of research groups and so there is an establishing comfort zone when similar results are obtained and an excellent discussion forum in the case of apparently Green Chemistry April 2002 DOI 10.1039/b202711a FOREWORD G25 business holding a US Patent on ionic liquid synthesis to stifle the academic freedom of American researchers.Following the Spring 2001 ACS National Meeting in San Diego all the American university attendees but none of the European received a letter. Amongst other statements was included “we wish to advise you that Patent Law grants no [such] exemption to academic institutions or to the employees thereof. Therefore an academic investigator (like any other investigator) who wishes to make or use ionic liquids that fall under the scope of [our] patent must first obtain our permission to do so.In respect to making such ionic liquids the investigator must take a license from [us]. In respect to using such ionic liquids the investigator must either obtain them from [us] or come to an agreement with [us] that authorizes their procurement from a third party source. To practice our patented technology without our permission will be construed by [us] as infringement. [We] reserve the right to protect [our] Intellectual Property as [we] deem necessary.” I will leave it to the reader to come their own conclusion about the motives of the writer but this is not only a blatant attempt to stifle academic freedom and control the direction of academic research but it also suppresses American research at the expense of European research.It would be immensely damaging if anyone took this letter seriously not least to the company involved who can only themselves benefit as new applications for their patented materials emerge. To conclude this commentary upon the current state of ionic liquids it is worth saying that their impact is already immense. Apart from the excitement of the research they are entering University undergraduate and postgraduate courses and even some schools. They are routinely mentioned as part of governmental green chemistry policy and have moved from academic curiosity to mainstream research in less than a decade. But the acid test is looming; there is now a need to see ionic liquid technology practised in industry to parallel the recent commercialisation of supercritical fluid technology by Thomas Swan in a newly commissioned plant in Consett (County Durham).To quote Professor Paul T. Anastas White House Office of Science and Technology Policy in Washington D.C. and advisor to both President Clinton and President Bush (as reported in Chemical & Engineering News) “Green chemistry aims to design the hazards out of chemical products and processes including solvents. With ionic liquids you do not have the same concerns as you have with for example volatile organic solvents which can contribute to air pollution. Ionic liquid chemistry is a very new area that is not only extremely interesting from a fundamental chemistry point of view but could also have a very large impact on industry.” It is up to us to prove this to be right! FOREWORD diverse findings.Following the first international conference focussing entirely on ionic liquids (a NATO ARW on Green Industrial Applications of Ionic Liquids Heraklion Crete 12–16 April 2000) there were ten sessions concerning the green applications of ionic liquids at the Spring 2001 ACS National Meeting in San Diego ten sessions are planned concerning the green applications of ionic liquids at the Autumn 2002 ACS National Meeting in Boston and a DeChema meeting on Green Solvents for Catalysis will be held in Bruchsal Germany in October 2002. Also 2002 will see the publication of three edited books devoted entirely to ionic liquids and there is this special issue of Green Chemistry.Figure 2. The attendees at the First International Meeting on Ionic Liquids a NATO ARW on Green Industrial Applications of Ionic Liquids Heraklion Crete 12-16 April 2000. The above is part of the healthy development of any significant area of chemistry. But it is essential that the diversity of the audience is maintained. One of the glories and fascinations of ionic liquids is that they impact on every area and aspect of chemistry and overlap with many areas of physics biochemistry chemical engineering and even (recently) space flight! There are and have been a number of attempts to launch a journal of ionic liquids. It is my belief and that of many others that this would be a disastrous move for the field. Ionic liquid results should be dispersed over a broad base of academic disciplines not concentrated in one place which would inevitably create the impression of a niche area. Indeed green chemistry will have succeeded when it is so well accepted that the adjective green can be dropped; ionic liquids will have succeeded when they are used for synthesis without especial comment in the way that methanol is used today. Would we ever have seriously considered a Journal of Methanol? If the above developments can be described as healthy then we must also beware the cancer. A serious threat to the area of ionic liquids is the quite incredible attempt of a small American Green Chemistry April 2002 G26 This journal is © The Royal Society of Chemistry 2002 Kenneth R. Seddon Queen’s University Belfast

ISSN:1463-9262    

DOI:10.1039/b202711a

出版商:RSC    

年代:2002

数据来源: RSC