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1. |
Green Chemistry: a new phase |
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Green Chemistry,
Volume Unassigned,
Issue Advance Articles,
1999,
Page 1-1
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摘要:
Green Chemistryhas been a major success story ever since the first volume was published in February 1999. Therefore, it was a great honour for me when I was approached and asked whether I would be willing to follow James Clark as the Scientific Editor for this journal. At the same time, I realised that it would be a very challenging task to foster the successful growth of such a well-renowned journal. However, I was more than happy to devote myself to this endeavour as I am absolutely convinced that both the journal and the field ofGreen Chemistryhave many reasons to be optimistic for their future development.It would have been impossible forGreen Chemistryto actually materialize as a journal on our PCs or desks and in many libraries without the dedication and the excellent work of the first Scientific Editor James Clark and his team at York. The most recent evidence for the prospering development seeded through this effort is the decision of the Royal Society of Chemistry to increase the publication rate ofGreen Chemistryto 12 issues per year from 2004. In a situation where many long-existing journals are facing increasing difficulties through budget cuts in libraries, this step constitutes at the same time a reward for a truly successful history and a challenge for the future.Green Chemistryis all set to accept that challenge! The Editorial Board headed by Colin Raston and the International Advisory Board continue to shape the journal to become one of the leading sources of reference in chemistry and its neighbouring disciplines. The RSC team led by Harp Minhas as the Managing Editor handles all publishing affairs efficiently and – with the aid of the referees – ensures rapid turnaround of manuscripts. Authors from all over the world submit fascinating research articles in a variety of disciplines and the latest impact factor of 2.54 in 2002 indicates that this work is followed by a very broad and active audience.Scientific publications addressing the field of “green chemistry” are emerging rapidly in many places. In the period 1999–2002, the number of publications with this key word has more than doubled every year and as of December 2003 over 1700 entries can be identified in SciFinder. Interestingly, this includes a significant number of patents and patent applications. Naturally, a large portion of these contributions deal with synthetic chemistry, but important areas such as life cycle assessment, toxicology, and green engineering are also at the heart of the development. Thus, the pool of potential contributions for the journalGreen Chemistrycan be expected to expand substantially in the next few years. At the same time,Green Chemistrywill continue to establish rigorous scientific standards to attract top quality contributions. In 2003 the acceptance rate was just over 30% and maintaining and fostering these rigorous criteria will help to strengthen the journal’s “scientific spine.”Green Chemistrycan also capitalize on its role as a reliable catalyst for encouraging communication between researchers, institutions, governmental bodies, funding agencies, and the public. The News and Views section forms an ideal platform for exchange of the latest news on events and trends. Conference announcements and reports are, for example, an integral part of this information. The section also features Highlights from other journals and – a relatively new format – Research Profiles of eminent scientists in the field. It would be nice to see this section used increasingly also as a forum to express opinions and for scientific debate. Markus Hölscher has accepted responsibility as the new “News Editor” and any information that seems suitable for this part of the journal can be submitted either to him or to the Cambridge Office directly.Thus, there is no doubt thatGreen Chemistryhas grown up, both as a journal and as a field of scientific endeavour. As a visualisation of this maturation, research articles are no longer accompanied by the “Green Boxes” that helped to define the context of the contributions in the early phase. All the enthusiasm and the hard work of those involved in the making ofGreen Chemistrywould have been in vain, however, without the excellent scientific work of all the authors and without the critical interest of their audience. Therefore, I would like to encourage you to continue to send your best work toGreen Chemistryand to make your colleagues aware of the benefits of publishing in the leading journal in the field.I wish all colleagues, authors, and readers a peaceful year in 2004, happiness in their private life, fruitful research in an exciting science, and success withGreen Chemistry!Professor Walter LeitnerScientific Editor,Green Chemistryleitner@itmc.rwth-aachen.de
ISSN:1463-9262
DOI:10.1039/b316109a
出版商:RSC
年代:2003
数据来源: RSC
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2. |
New Board Member |
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Green Chemistry,
Volume Unassigned,
Issue Advance Articles,
1999,
Page 2-2
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摘要:
Steve’s academic interests focus on the utilisation of supercritical carbon dioxide for polymer synthesis, polymer processing and preparation of novel polymeric materials for tissue engineering and drug delivery. Steve currently holds a chair of Chemistry at the School of Chemistry, University of Nottingham and prior to this held a Royal Society University Research Fellowship (1991–1999). In 2001 he was recipient of the Jerwood–Salters Environment Award and the Corday–Morgan Medal and Award of the Royal Society of Chemistry. In 2003 he received a Royal Society–Wolfson Research Merit Award. A more detailed description of his research and some movies of supercritical fluids can be viewed athttp://www.nottingham.ac.uk/∼pczctg/Index.htm
ISSN:1463-9262
DOI:10.1039/b315801m
出版商:RSC
年代:2003
数据来源: RSC
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3. |
Highlights |
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Green Chemistry,
Volume Unassigned,
Issue Advance Articles,
1999,
Page 3-4
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ISSN:1463-9262
DOI:10.1039/b313721j
出版商:RSC
年代:2003
数据来源: RSC
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4. |
Green approaches: a new horizon for future scientists |
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Green Chemistry,
Volume Unassigned,
Issue Advance Articles,
1999,
Page 5-9
Darren Anderson,
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IntroductionIt’s time to accept our share of responsibility for the modern state of the world. With real concerns mounting on the state of global sustainability and newer considerations such as endocrine disruption, we must aggressively pursue the ideals of green chemistry.We are a new generation of scientists. We have chosennotto ignore the potential consequences of our chosen professions. We realize that we have responsibilities in the education, acceptance, and implementation of green chemistry principles.As a new generation of scientists and engineers, we need to recognize that our actions and decisions will affect the future well being of our planet. While we have the tools to create products and processes that improve our quality of life, we must consciously make choices to ensure that our actions do not endanger life or the environment around us. We strongly believe that by applying the principles of green chemistry to all aspects of science and engineering, we can continue to improve the society in which we live without simultaneously harming it.In a field where one cannot always go to the literature to discover the answers that one seeks, the Pan-American Advanced Studies Institute on Green Chemistry (PASI-GC) gave us the opportunity to network with people leading their field. Through this program we gained valuable professional experiences as individuals; however, we also realized that these ideals must spread beyond our inner circle in order to be truly effective.The dissemination of green chemistry will be no easy task. Interdisciplinary cooperation between all scientific fields will be necessary to create new methods of measuring the toxicity, environmental impact, and energy requirements of new and existing chemical compounds and commercial materials. This technology and theory must then be implemented into as many industrial, academic, and government applications as possible. This unique conference has given us the tools to aggressively pursue these goals, rather than to merely talk about them.Two weeks of intensive presentations, discussions, and actual laboratory time pertaining to green chemistry, its theory, policy, and application, made this a conference like none before it. There were no hierarchical communication barriers between the students involved and the presenters and organizers of this event. The ability to converse casually yet meaningfully about current and future technologies with the people who were responsible for their existence was an experience previously unmatched. This event will have a special place in the memories of all involved for some time to come, as both a model of interaction and an impetus for change.In this report, we wish to convey the ideology we have acquired through the PASI on Green Chemistry and emphasize how much is still left to be accomplished in the field. We begin with a description of the PASI-GC, followed by a discussion of why green chemistry is important, the multinational and multidisciplinary aspects of the field, and its role in education. We conclude with some specific actions we believe are important for the advancement of green chemistry. We hope to encourage all to reflect upon our actions and beliefs as scientists, ensuring that we promote the principles of green chemistry1to the greatest extent.
ISSN:1463-9262
DOI:10.1039/b314167p
出版商:RSC
年代:2003
数据来源: RSC
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5. |
Green Chemistry 2005: new look, new people, new chances |
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Green Chemistry,
Volume Unassigned,
Issue Advance Articles,
1999,
Page 7-8
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With the publication of this first issue ofGreen Chemistryin 2005, we would like to give you a brief update on the development of the journal in the past year and on some important changes that have been introduced with the beginning of this year.Journal changesReaders will have noticed that the journal has a striking new look for 2005. The new modern cover design and size makesGreen Chemistryimmediately recognizable as part of the successful RSC journal family. Individual issues will now feature artwork from the most significant paper/review within the issue at the invitation of the Editor thus enhancing the impact of the journal.A news publicationChemical Technologyforms part of the introductory pages ofGreen Chemistry. This publication draws together news and research highlights from a variety of RSC publications and provides a snapshot of developments across the chemical technology sector. The introduction ofChemical Technologyalso allows the inclusion of full colour contents lists with graphical abstracts making it easier for you to browse for your favourite article whenGreen Chemistryarrives on your desk. To enhance readability and impact further the font size in the journal has also been increased.Furthermore, you will notice that “G” pages have disappeared from the journal in order to achieve greater consistency with other RSC journals. The news material will, however, remain an important part of the journal and we encourage the submission of essays, conference reports and other relevant information to the News Editor.Editorial Board changesWith the turn of the year, the Editorial Board has also seen considerable changes owing to the fact that a number of members have completed their term at the end of 2004. Throughout the year, there are still other changes in the pipeline as current members complete their three year terms and we will announce these at the appropriate time.At this stage, we say farewell to Professor Tony Barrett, Professor Terry Collins, Dr Leo Petrus, and Dr Adisa Azapagic with heartfelt thanks for their excellent commitment and support for the journal over the last three years. Their efforts have been pivotal in the success story ofGreen Chemistry!At the same time, we welcome our new Editorial Board Members in 2005. We are happy and proud to announce that Professor C. J. Li (see photo and biography in issue 2) has joined the Board as our new North American Editor forGreen Chemistry. Together with Professor Paul Anastas, Professor Roshan Jachuk and Professor Tom Welton, the new team is lined up nicely to shape a bright future for the journal.Submissions, publication times, and impactThe ever increasing numbers of papers submitted to the journal continue to reflect the growing interest inGreen Chemistryas a subject and journal. Our publication times remain amongst the fastest in the field, with average receipt to publication times of around 100 days, ensuring your research is given the highest priority. At the same time,Green Chemistryis now more conscious than ever that it has to maintain the highest possible scientific standards. As a consequence, the acceptance rate was consistently around 30% throughout 2004. This stringent policy is supported by a rising impact factor reaching 2.82 in 2004.Supporting our authors and refereesThe RSC has developed a number of tools to help our authors and referees through the publication process andGreen Chemistryauthors can take full advantage of these developments.ReSourCeprovides authors and referees with a single web account for their publishing activities with manuscript tracking and proofing facilities. Authors are also able to access a list of their previous manuscripts and for published articles collect their free PDF reprints and link to the online articles. For further details, please check outhttp://www.rsc.org/resource.A recent collaboration with the Unilever Centre for Molecular Science Informatics (at the University of Cambridge, UK) has resulted in theExperimental Data Checker—a java applet which analyses experimental data. Again further information is found at the corresponding web pagehttp://www.rsc.org/is/journals/checker/run.htm.Thank youFinally, and most importantly, we would like to express our thanks and gratitude to everyone who has supportedGreen Chemistryby contributing excellent papers, providing valuable and speedy referees' reports, or any other form of collaboration. It has been great fun to work with you over the last year and we look forward to reflecting the continuing growth of the Green Chemistry Community and its scientific achievements in the years to come.We wish you all a peaceful turn of the year and every success in 2005! Walter LeitnerScientific Editor Harp MinhasManaging Editor
ISSN:1463-9262
DOI:10.1039/b418779m
出版商:RSC
年代:2004
数据来源: RSC
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6. |
Origin of the mediator losses in electrochemical delignification processes: primary and secondary reactions of violuric acid andN,N′-dimethylvioluric acid radicals with lignin model compounds |
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Green Chemistry,
Volume Unassigned,
Issue Advance Articles,
1999,
Page 8-14
Markus Mickel,
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Green ContextThe development of more environmentally benign alternatives to chlorine in pulp bleaching processes is an important large scale industrial challenge—Redox mediators and more recentlyN-hydroxy compounds have been proposed for this purpose. They generate radicals in the presence of enzymes, and these in turn cause pulp delignification. Unfortunately, significant quantities of these ‘mediators’ are lost in the delignification process. This paper analyses this loss, explains its cause and thus opens the door to improved mediator design. Thus electrochemical mediator-based delignification is shown to be an attractive alternative to existing chlorine-based processes.JHC
ISSN:1463-9262
DOI:10.1039/b208812f
出版商:RSC
年代:2002
数据来源: RSC
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7. |
Biodegradable ionic liquids |
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Green Chemistry,
Volume Unassigned,
Issue Advance Articles,
1999,
Page 9-14
M. Teresa Garcia,
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Dr M. Teresa Garcia received her Ph.D. in chemistry from the University of Barcelona, Spain in 1990. She is currently a research associate in the Surfactant Technology Department of the Chemical and Environmental Research Institute of Barcelona (IIQAB) belonging to the Spanish National Research Council (CSIC). Her research interests include environmental chemistry and ecotoxicology of surfactants.
ISSN:1463-9262
DOI:10.1039/b411922c
出版商:RSC
年代:2004
数据来源: RSC
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8. |
A brief structured view of green chemistry issues |
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Green Chemistry,
Volume Unassigned,
Issue Advance Articles,
1999,
Page 10-12
Ramon Mestres,
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摘要:
Green chemistry is commonly presented as a set of twelve principles, fruit of great intuition and chemical common sense, together with the related concepts, research fields and significant results which have emerged from the principles.1–9It might be worthwhile now to provide some kind of order or structure to the aims, concepts, research areas, implications and connections of green chemistry, which may facilitate its presentation for the education of future and young chemists. Although the present article is just an incipient attempt, it has the virtue of being open to many additions.Green chemistry is part of a wide multidisciplinary area, comprehensively termed Chemistryandthe Environment, where chemistry focuses its attention on the links existing between anthropogenic activity and environmental contamination by chemicals. Within this, the observation and understanding of the harmful effects, origin, mobility and persistence of chemical pollutants is the subject of Chemistryofthe Environment, whereas the term Chemistryforthe Environment denotes striving for provision of chemical solutions to chemical contamination. The desired decrease in the concentration of pollutants could in principle be attained by removing them from the environment, when already present, by preventing their dissemination, when still confined, and especially, by avoiding their generation. The last of these is none other than the aim of green chemistry.It may be a matter for discussion whether green chemistry can be expected to afford adequate answers to chemical contamination derived from sources other than anthropogenic chemical activity, but there cannot be any doubt that the main objective of green chemistry is the chemical process itself and the final products of the chemical industry, employed by other industries or activities.The introduction of mineral or organic fossil material from under the earth’s surface into the production stream may be regarded equivalent to the preparative generation of chemicals and justifies that contribution to reduction of use of these materials may be assumed to be within green chemistry’s aims.Up to this point green chemistry has been presented in the context of chemistry and the environment, where it in fact was born. Indeed, there would be no green chemistry without the prior concern for contamination by chemicals. However, it must be also be acknowledged that green chemistry is not only meant to improve the environment but also to provide the chemical industry with a new view for overcoming the serious issues met as a consequence of its being the source of a great deal of the chemical pollution and, consequently, the culprit of environmental damage. Realisation of a number of present and future problems existing for chemistry and the conviction that convenient chemical solutions can be attained by application of green chemistry philosophy become the starting point for the structure of green chemistry.These problems may be enumerated as follows:Pollution through chemicalsRisks caused by dangerous chemicalsExhaustion of sources of primary materialsWhen pollution by chemical contamination is taken into account, it is possible to realise that many of the polluting chemicals are synthetic and that they are released to the environment, in a more or less continuous flow, by chemical industries. Fluids leak; waste materials are either disposed of or released as aqueous effluents. A significant proportion of the final products of chemical industry are disseminated into the environment; not by the chemical industry that produced them, but by other industries or activities which employ these products in agriculture, textile, building, automotive, cleaning, pharmacy,etc.It may be convenient to recognise here the existence of a significant quantitative distinction betweendangerousandpollutingchemicals. Highly toxic, flammable, explosive or aggressive chemicals, which have been or can be the cause of highly dramatic personal or public events are here categorised simply asdangerouschemicals. They are nothing new to chemists and have been a permanent cause of concern since their early industrial application in the XIXth century.Polluting chemicals are certainly harmful and dangerous, but rather through long term effects: ecotoxicity, greenhouse effect, depletion of stratospheric ozone,etc. The noxious effects of many pollutants have frequently been unforeseen by chemists. It may then be convenient to maintain a distinction between prevention of release of pollutants and precaution against immediate serious personal harm.Industries have usually dealt with these chemical pollution and safety issues by introduction of a kind of palliative engineering technology, which requires great unprofitable expenditure, frequently without attempting modification of the chemical process itself. Industries have also met awkward situations when final products already launched into market have subsequently been found to be harmful to humans or to the environment. The green chemistry approach to all these pollution, immediate risk and noxious final product situations is that it is better and cheaper to find new, cleaner and safer chemical technologies for the synthesis of a particular chemical and to know to what extent a final product may be harmful before it is first synthesised in the laboratory.The third problem for chemistry identified here derives from the depletion of fossil feedstocks for chemical industry. Although how far into the future complete exhaustion may occur is open to discussion, the shortage of easily recovered oil will certainly cause a rise in feedstock prices in the near future. This leads to the need for the use of renewable feedstocks and for the modification or development of novel chemical technologies for this purpose. It cannot be overlooked that other materials and water are or may become scarce either locally or at global level. This accessibility to resources must also be considered if development of young nations and the future sustainability of chemistry is to be guaranteed.From what has been said so far four general objectives can be derived from green chemical philosophy.1 Reduction of use and generation of polluting chemicals in the chemical process2 Reduction of use of dangerous chemicals in the chemical process3 Reduction of the harmful effects of final products4 Reduction of the use of exhaustible feedstock materials and of scarce resourcesWhen the reduction of use and generation of polluting chemicals is considered, attention must be paid first of all to the chemical process and to all that it implies, namely starting materials, reagents, solvents, isolation and purification of the product and treatment and disposal of by-products. The ultimate aim is an ideal process that starts from non-polluting starting materials, leads to no secondary or concomitant products and requires no solvents in order to carry out the chemical conversion or to isolate and purify the product. Such an intrinsically clean process seems unattainable, but it is to be expected from the ingenuity and resourcefulness of chemists that, as the result of a single modification or more probably from successive approaches, a much more satisfactory process than that currently in operation will be achieved.General objectives for the chemical process, along with related concepts, namely selectivity, and atom economy, some intermediate objectives and procedures to attain them are shown inTable 1, together with some significant areas of research where progress can be expected to help to achieve substantially cleaner processes.Reduction of use and generation of polluting chemicals in the chemical processGeneral objectives andrelated conceptsIntermediate objectivesAreas of researchUse of non-polluting starting materialsRenewable resourcesChemicals near to the sources Reduction of secondary products in chemical processesSelectivitySelective novel reactionsCatalytic and biocatalytic proceduresSelectivity of current reactionsReaction mechanismsReal time control of ongoing processesContinuous processesProcess intensificationReduction of number of synthetic steps Reduction of environmentally significant concomitantsAtomic economyNew procedures with no environmentally significant concomitantsCatalytic and biocatalytic proceduresReactions with O2, N2, H2O as concomitantsReduction of number of synthetic stepsCatalytic and biocatalytic procedures Reduction of use of polluting solvents as reaction mediaReactions without solventSolventless reactionsReactions in special solventsReactions in waterSolvents under supercritical conditionsIonic liquidsReactions in low toxicity organic solvents Reduction of use of polluting solvents for separation or purificationNo secondary productsSeparation and purification proceduresSolvents under supercritical conditionsReaction conditions with separation of productsBiphasic conditionsPolymeric reagentsHeterogeneous catalysis Reduction of energy consumptionChemicals close to the sourcesReactions at room temperatureA similar approach can be assumed for the reduction of danger, as shown inTable 2. Dramatic events are usually linked to solvents, reagents, or reaction conditions. Little need to be added here about solvents, except to say that solvents are not usually both persistently polluting and dangerous.Reduction of use of dangerous chemicals in the chemical processGeneral objectives andrelated conceptsIntermediate objectivesAreas of researchProcesses without dangerous reaction solvents Processes without dangerous solvents for separation and purification Processes without dangerous reagentsSafer reagentsCatalytic and biocatalytic procedures Safer reaction conditionsMild reaction conditionsSelective activation techniquesPhotochemistryElectrochemistryMicrowavesSonochemistryRoom temperature and ordinary pressureReduced scaleContinuous processesProcess intensificationBroadly speaking, it may be assumed that the dangerous character of reagents is associated with their high reactivity, frequently due to their highly positive enthalpy of formation, or to a high enthalpy for their reaction with oxygen or water. Use of less reactive reagents will require higher reaction temperatures, a feature which will increase reaction risk and decrease selectivity. Milder reagents can become convenient and effective when an adequate catalyst causes a reduction of the activation enthalpy. Catalytic methods are thus expected to provide suitable conditions for use of safer milder reagents. Mild conditions using poorly reactive reagents can also be attained by adequate selective energy sources, which activate one of the reacting molecules above or near the energy of the transition state. This is the case for photochemical or electrochemical processes or for sonochemical or microwave activation.A great variety of industries and productive sectors employ chemicals with harmful and noxious after-effects, which frequently end up disseminated in the environment unchanged or chemically modified. Reduction of these harmful effects requires a knowledge frequently lacking in chemical education, namely toxicity and ecotoxicity. Thus, the launching of new products into the market will require learning first how to establish the toxicity and ecotoxicity of a chemical structure before it has been prepared. As shown inTable 3, use of natural products, whenever possible, may be a good guarantee of dealing with ecotoxicologically harmless substances, even when they are toxic. Especially interesting for pest control is the use of natural chemicals, whether naturally or synthetically produced, which can alter the specific physiology or behaviour of insects or other pests.Reduction of the harmful effects of final productsGeneral objectives andrelated conceptsIntermediate objectivesAreas of researchHarmless final productsNatural productsBioactive products based on specific physiology and behaviourNew harmless productsDesign of intrinsically non toxic chemicals Degradable products after their functionDesign of degradable materials Recyclable products after their functionDesign of recyclable materialsChemical materials which are used in large amounts should ideally be easily recovered by any convenient form of recycling, or degraded under easily controlled conditions. The same comment about the foreknowledge of toxicity would apply here in order to succeed in the design of useful materials which could be cheaply and easily recycled or degraded.Last, but not least, as far as possible fossil derived feedstocks must be substituted and renewable feedstocks, mostly plant derived, must be developed (Table 4). The largest amount of such plant derived materials is biomass. There is a renewed interest in the use of biomass for production of fuels and of basic chemicals and solvents. When combined with biotechnological methods biomass may become the carbon source for the production of advanced intermediates or final products. Materials obtained from renewable specific production, namely vegetable oils or starch and traditional natural products, as carotenoids or quinine are now receiving special attention. It may be added here that recycling of large bulk materials may also become a form of recovering part of the fossil derived feedstocks.Reduction of the use of exhaustible feedstock materials and of scarce resourcesGeneral objectives andrelated conceptsIntermediate objectivesAreas of researchDevelopment of renewable sources of feedstocksBiomassProduction of fuelsProduction of basic chemicalsProduction of synthetic intermediates and final productsRenewable materials for specific productionProduction of basic chemicalsNatural productsProduction of synthetic intermediates and final productsRecycled materialsFeedstock recycling of plastics Improvement of efficiency in use of non-renewable sourcesReduction of energy consumptionImprovement in generation of energy Improvement of efficiency in use of scarce sourcesEconomy of waterReduction of the depletion rate of fossil materials may come also from increasing the efficiency in use of fuels. This is expected, for instance from the development of fuel cells.In conclusion, this article presents here a first attempt at providing a structure or scheme for some of the concepts and issues related to green chemistry, which may become valuable for the education of young and future chemists. The present structure is amenable to change and addition. Where some particular issues have been placed in this scheme may be a cause of argument. Photochemistry, for instance, is not constrained to the provision of safer reactions to the synthetic chemical armoury, but it is true that typical photochemical reactions do not require use of strong reagents. Similar comments could be made about the place for other issues. Thus, many published results show that other activation techniques go hand in hand with solvent free reactions. Catalytic methods, including biocatalysis, are exceptional in being found in the scheme in connection with selectivity, atomic economy and safety. This should not be surprising when it is considered that the great source of inspiration for green chemistry is no other than nature, especially in its living chemical reactors, where selectivity, atomic economy, and mildness of reactions are at their utmost.
ISSN:1463-9262
DOI:10.1039/b314467b
出版商:RSC
年代:2003
数据来源: RSC
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9. |
Green Chemistry… 10 years on |
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Green Chemistry,
Volume Unassigned,
Issue Advance Articles,
1999,
Page 11-12
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摘要:
Editorial BoardWe would like to welcome Professor Shu Kobayashi, Tokyo University, onto theGreen ChemistryEditorial Board from this year. Professor Kobayashi’s longstanding and world-renowned experience in efficient synthetic methodologies including asymmetric catalysis, organic reactions in water, microencapsulated catalysts, and microreactors in organic synthesis will provide an additional regional link forGreen Chemistryin Asia. Shu has been a stimulating plenary speaker at many green chemistry conferences and his research has been recognised with a long list of prestigious awards, including most recently the Arthur C. Cope Scholarship and Howard Memorial Lectureship. We look forward very much to his input and collaboration within the editorial board.
ISSN:1463-9262
DOI:10.1039/b820904a
出版商:RSC
年代:2008
数据来源: RSC
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10. |
Succinic acid from renewable resources as a C4building-block chemical—a review of the catalytic possibilities in aqueous media |
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Green Chemistry,
Volume Unassigned,
Issue Advance Articles,
1999,
Page 13-26
Clara Delhomme,
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摘要:
1. IntroductionPrior to the end of the 18th century, the economy was largely based on agriculture; however, the industrial revolution changed this, establishing fossil fuels (petroleum, coal and natural gas) as the main resources. In continuation of this development, the chemical industry nowadays consumes more than 1 billion barrels of oil per year.1Considering this consumption and the limited nature of the fossil fuels, it is not astonishing that the economy faces several problems—a continuously rising price of oil, political and economic issues related to the unequal distribution of the remaining oil stocks and increasingly severe environmental impacts due to the use of these resources and the by-products generated during their consumption.These problems have motivated the industry to find alternatives to fossil fuels. Considerable effort is being invested in biotechnology and “green chemistry” (among others) to develop a chemical industry based on renewable resources as at least (a partial) substitute for the dwindling fossil fuels. To that end, fermentation of biomass for the production of renewable building-block chemicals is currently being developed. The so-called “green chemistry” deals to a considerable extent with the optimization of chemical processes, reducing the negative environmental impact of the chemical industry,e.g.by lowering energy consumption, with more efficient catalysts and by enabling use of solvents with a lower environmental impact. Furthermore, bio-based feedstock (produced by fermentation) must be transformed into valuable chemicals. Since the output of fermentations consists usually of dilute aqueous solutions of organic products, new water-stable catalysts need to be designed for such applications.Succinic acid is among the new bio-derived building-block chemicals that could replace the current maleic anhydride C4platform. The main interest in succinic acid lies in its derivatives,1since it can be transformed into a lot of interesting products: 1,4-butanediol (BDO), γ-butyrolactone (GBL), tetrahydrofuran (THF),N-methyl-2-pyrrolidone (NMP), 2-pyrrolidone (2-Pyrr), succinimide, succinic esters, maleic acid (M.A.)/maleic anhydride (M.Anh.) and several others (cf.Fig. 1).Succinic acid derivatives.2The optimization of the fermentation process for succinic acid production is currently underway. To that end, various natural succinate producing strains of bacteria (e.g. Anaerobiospirillum succiniciproducens,Actinobacillus succinogenesandMannheimia succiniciproducens) and engineeredEscherichia colistrains have been investigated.3However, among the bottleneck problems of the industrial production of succinic acid from renewable resources remain the costs related to purification.4Because the fermentation must be done at neutral or low acidic pH, the fermentation broth must be acidified upon conclusion of the reaction to create the free acid. Furthermore, other organic acids produced as side products during the fermentation can unfavorably affect the recovery of succinic acid.4Therefore, the direct downstream catalysis of succinic acid in the filtered aqueous fermentation broth allows the production of valuable derivatives without the need to isolate pure succinic acid.In the past century, the utilization of water as a reaction medium for organic synthesis was quite limited. The low water-solubility of most organics and the water-sensitivity of some reagents or intermediates5were serious disadvantages. However, the high waste production due to organic solvents, their volatility and the high energy consumption for gas phase reactions are two major environmental drawbacks for the chemical industry that must adapt to new environmental restrictions and to growing consumer awareness. Furthermore, the handling of flammable, explosive and carcinogenic organic solvents is a major safety problem. Water—an abundant and non-toxic solvent—could be a greener alternative as well as having other advantages: it favors ionic reactions, solvates cations and anions, is an ideal solvent for radical reactions, can facilitate the control of exothermic reaction due to its high phase change enthalpies and heat capacity6,7and, finally, water has been reported to suppress the coke and tar formation for the vapor hydrogenation of maleic acid with metal containing catalysts.8Furthermore, in opposition to liphophilic oil, coal or natural gas derived compounds, the chemicals produced from renewable resources are often hydrophilic. Hence, a new class of catalysts must be developed. These new catalysts must fulfill the following requirements: (1) water-stability, (2) high selectivity towards substrate and product, (3) no inhibition due to or degradation by fermentation side products, (4) immobilizability to enable easy recovery, (5) high activity at low pressure and temperature (ideally atmospheric pressure and room temperature so as to minimize energy requirements). Furthermore, the chemicals produced from the fossil fuels are mostly in a low oxidation state and must therefore be oxidized, whereas the compounds produced from renewable resources are often in a high oxidation state and must therefore be reduced. Current catalysts must therefore be substantially modified so that they are able to catalyze reductions of bio-based chemicals in aqueous media.In the case of succinic acid, most derivatives presented inFig. 1are produced through hydrogenation or reductive amination (in the presence of hydrogen), hence, this review will focus on these types of reactions for production of succinic acid derivatives in presence of water. Additionally, some space is dedicated to the synthesis of succinic acid by the hydrogenation of maleic and fumaric acid with the help of aqueous organometallic catalysts. Although at first glance, this approach seems not to be relevant to succinic acid derived from renewable feedstock, it might nevertheless be helpful in the design of water-stable homogeneous or immobilized catalysts that are able to hydrogenate the renewable succinic acid in an aqueous environment. A summary of achievements in the area of organometallics for solvent hydrogenation of succinic anhydride has been added as further information and for comparative purposes.
ISSN:1463-9262
DOI:10.1039/b810684c
出版商:RSC
年代:2008
数据来源: RSC
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