摘要:

AbstractA computer simulation model for suspension flows in plate‐and‐frame type membrane modules has been developed. Reduced forms of the mass transport and momentum equation were solved simultaneously to study concentration polarization and permeation flux decline. The verified simulator can be used to analyze and predict the process dynamics and can aid in the design of ultrafiltration syst

ISSN:0001-1541    

DOI:10.1002/aic.690290402

出版商:American Institute of Chemical Engineers    

年代:1983

数据来源: WILEY

摘要:

AbstractCalorimetry was used to determine the heat of reaction and equilibrium constant at 318 K for the reaction between maleic anhydride (A) and 2‐methyl furan (B). The values were −60 kJ/gmol and 614 cm3/gmol, respectively. The motivation for this work was to find a single phase‐reacting system that could be used to store solar energy. Thus, the energy storage capacity was calculated for a mixture ofAandB, both initially at 7 kmol/m3, in dioxane. The maximum apparent heat capacity of 7.37 J/cm3·K occurred at 334 K. This maximum value is 76% higher than the heat capacity of pure

ISSN:0001-1541    

DOI:10.1002/aic.690290403

出版商:American Institute of Chemical Engineers    

年代:1983

数据来源: WILEY

摘要:

AbstractA new flexible method has been developed for modelling multistage multicomponent separation processes. The method is based on the simultaneous modular approach and can be referred to as a quasilinear two‐level modelling. The network is solved within each iteration as a linear one, and after each network solution the split streams are updated modularly using nonlinear submodels. The method is suited for modelling the most important separation processes with arbitrary structure and permits to use different models for the subunits or processing units. Illustrative examples and computational results are presented showing the efficiency, flexibility and capability of the metho

ISSN:0001-1541    

DOI:10.1002/aic.690290404

出版商:American Institute of Chemical Engineers    

年代:1983

数据来源: WILEY

摘要:

AbstractThe permeation behavior of the high‐flux asymmetric membrane differs from that of the conventional symmetric membrane. A calculation method for predicting the gas separation performance of a permeator with asymmetric membrane is presented. The model takes into account the permeate pressure drop and is applicable to both hollow‐fiber and spiral‐wound modules. The effect of permeate‐feed flow pattern on module performance is analyzed. It is shown that for the high‐flux asymmetric membrane, the countercurrent flow pattern is not necessarily always the preferred operating mode. The mathematical model is verified by large‐scale field pilot‐plant experiments for helium recovery from natural gas using large hollow‐fiber module

ISSN:0001-1541    

DOI:10.1002/aic.690290405

出版商:American Institute of Chemical Engineers    

年代:1983

数据来源: WILEY

摘要:

AbstractA general method is developed for a systematic determination of criteria predicting steady‐state multiplicity in lumped‐parameter systems in which many irreversible reactions occur simultaneously. The method enables use of criteria derived for simple reaction networks to predict the behavior of more complex networks. The available multiplicity criteria for the single‐ and two‐reaction networks can always be used to write down sufficient multiplicity criteria for any multireaction system. Several examples illustrate the power of the proposed te

ISSN:0001-1541    

DOI:10.1002/aic.690290406

出版商:American Institute of Chemical Engineers    

年代:1983

数据来源: WILEY

摘要:

AbstractAn equation of state is obtained to describe the fluid state from the supercritical gas to subcritical vapor and liquid for small and large molecules of organic and inorganic substances. The perturbation theory of the fluid state is extended to include rotational contribution of molecular motion in addition to translational and the attractive force contributions. Three equation constants describe a substance and values are presented for 22 substances. Application is made to mixtures with emphasis on their phase equilibria.

ISSN:0001-1541    

DOI:10.1002/aic.690290407

出版商:American Institute of Chemical Engineers    

年代:1983

数据来源: WILEY

摘要:

AbstractSolasodine fromSolanumplants is a potential raw material for steroid drug manufacture. Acid hydrolysis of the naturally occuring glycosides of solasodine is a major step in production of the aglycone. As part of a detailed study of the hydrolysis of solasodine glycosides, the hydrolysis procedure has been mathematically modelled. Two models are presented and have been used to obtain kinetic data for the reactions at a number of different reaction conditions. The subsequent conversion of solasodine to solasodiene is considered in Part II of this paper; the combined reactions and guidelines for commercial hydrolysis are presented in Part III.

ISSN:0001-1541    

DOI:10.1002/aic.690290408

出版商:American Institute of Chemical Engineers    

年代:1983

数据来源: WILEY

摘要:

AbstractThe undesirable conversion of solasodine product to solasodiene which occurs during the acid hydrolysis of solasodine glycosides has been mathematically modelled. The model incorporates acid loss which results from reaction of acid with alcohol solvents. The model has been used to obtain kinetic data for the reaction at a number of different reaction conditions.

ISSN:0001-1541    

DOI:10.1002/aic.690290409

出版商:American Institute of Chemical Engineers    

年代:1983

数据来源: WILEY

摘要:

AbstractKinetic models for glycoside hydrolysis and solasodiene formation are combined, and using previous experimental data the effect of changes in reaction conditions on hydrolysis times and the proportion of solasodiene in the final hydrolysed product are established. These are used to give a set of guidelines for commercial hydrolysis. The use of the models for new commercial situations is explained.

ISSN:0001-1541    

DOI:10.1002/aic.690290410

出版商:American Institute of Chemical Engineers    

年代:1983

数据来源: WILEY

摘要:

AbstractBatch/semicontinuous chemical plants are usually designed either by assuming infinite intermediate storage or by assuming that the units themselves act as storage vessels, while the storage vessels are sized by rules of thumb or experience. In this paper, the case of an intermediate storage vessel which links one upstream batch/semicontinuous unit to one downstream batch/semicontinuous unit is analyzed. The units are assumed to operate with fixed cycle times and capacities. Expressions for determining the minimum storage tank capacity necessary to decouple the two units are derived from a mathematical model of the periodic process. Effects of the relative starting times of the two units on the required storage capacity are determined, thus suggesting the optimum process timings to minimize the same. Application of the results is illustrated by an example.

ISSN:0001-1541    

DOI:10.1002/aic.690290411

出版商:American Institute of Chemical Engineers    

年代:1983

数据来源: WILEY