Comprehensive kinetic model

In this work, a comprehensive kinetic model, suitable for simulation of inilticomponent aiulsion polymerization reactors, is presented A well-mixed, isothermal, batch reactor is considered with illustrative purposes. Typical model outputs are PSD, monomer conversion, multivariate distritution of the i lymer particles in terms of numtoer and type of contained active Chains, and pwlymer ccmposition. Model predictions are compared with experimental data for the ternary system acrylonitrile-styrene-methyl methacrylate. 

Kim, T.J., Yetter, R.A., and Dryer, F.L., New results on moist CO oxidation High pressure, high temperature experiments and comprehensive kinetic modeling, Proc. Combust. Inst., 25, 759,1994. 

A comprehensive kinetic model addressing all the findings has not been developed. Some of the reported rate equations consider the self-poisoning effect of the reactant compounds, some other that effect of ammonia, and so on so forth. The reported data is dispersed with a variety of non-comparable conditions and results. The adsorption of the poisoning compounds has been modeled assuming one or two-sites on the catalyst surface however, the applicability of these expressions also needs to be addressed to other reacting systems to verity its reliability. The model also needs of validated adsorption parameters, difficult to measure under the operating conditions. 

J. P. Boitiaux, J. Cosyns, M. Derrien, and G. Leger, Proper design of butadiene selective hydrogenation process for maximum 1-butene yield by using comprehensive kinetic model, AIChE National Meeting (Houston, March 24, 1984). 

T.J. Kim, R.A. Yetter, and F.L. Dryer. New Results on Moist CO Oxidation High Pressure, High Temperature Experiments and Comprehensive Kinetic Modeling. Proc. Combust. Inst., 25 759-766,1994. 

The most comprehensive kinetic model for the synthesis of polyurethanes was developed by Macosko and his team.44"46 In all cases the heart of the model is the degree of conversion, p, which is defined for polyurethane synthesis as... 

The reaction and separation synthesis approach of Section 5 has been adopted to the problem of activated sludge process design (83). The conventional designs as well as all novel schemes for combined oxidation/denitrification of wastewater are explored. The process is optimized using a novel methodology for optimal reaction/separation network synthesis, supplied with a comprehensive kinetic model (84). The activated sludge process is synthesized using the systematic... 

The personal experience of the authors allows us to conclude that, in most cases, the development of a suitable comprehensive kinetic model is not limited by the development of a mathematical model but by the limitations of the experimental measurements. In fact, in chemical kinetics the experiments are very often expensive, in terms of time and money, and not all the kinetically relevant reaction intermediates can be measurable and even defined in their chemical structure. Thus, the testing of more detailed kinetic models may be hindered by the availability of experimental data. 

A comprehensive kinetic model for the free-radical polymerisation of vinyl chloride in the presence of monofunctional and bifunctional initiators,... 

The above flowsheet can be simulated by means of an appropriate simulation package. In the absence of a comprehensive kinetic model and of fundamental thermodynamic data the results will be only approximate, namely with respect to satisfying the quality specifications. However, the simulation allows the designer to obtain an overall view of streams, utilities and equipment, needed for an economic assessment. 

Peppley BA, et al. Methanol-steam reforming on Cu/ZnO/Al2C>3 catalysts. Part 2. A comprehensive kinetic model. Appl Catal A Gen. 1999 179(1 2) 31-49. 

The construction of a comprehensive kinetic model to represent the oxidation of a hydrocarbon, incorporating the best available kinetic parameters, permits a quantitative link to be forged by numerical computation between detailed chemical measurements and the interpretation of the underlying kinetics and mechanism of the combustion system. The first step is the simulation of composition-time profiles for intermediate and final products under conditions resembling the experimental study, as a validation of the model itself. Further insight may then be gained into the... 

Validation of comprehensive kinetic models for low-temperature oxidation... 

The chemical reactor has a determinant role on both the material balance and the structure of the whole flowsheet. It is important to stress that the downstream levels in the Hierarchical Approach, as the separation system and heat integration, depend entirely on the composition of the reactor exit stream. However, a comprehensive kinetic model of the reaction network is hardly available at an early conceptual stage. To overcome this shortcoming, in a first attempt we may neglect the interaction between the reactor and the rest of the process, and use an analysis based on stoichiometry. A reliable quantitative relationship between the input and the output molar flow rates of components would be sufficient. This information is usually available from laboratory studies on chemistry. Kinetics requires much more effort, which may be justified only after proving that the process is feasible. Note that the detailed description of stoichiometry, taking into account the formation of sub-products and impurities is not a trivial task. The effort is necessary, because otherwise the separation system will be largely underestimated. 

Based on this process schematization, a comprehensive kinetic model has been proposed [41, 42]. Its main features are ... 

In principal, the kinetic data base is infinitely large, and the practical reality for this to happen may be not too distant in the future.. .. This brings to bankruptcy the philosophy of comprehensive kinetic model and leads in a natural way to the following view. All conceivable chemical reactions with the associated rate parameters—available experimentally, eal-culated theoretically, or simply estimated—constitute a reaction data bank. Given a speeifie problem, a subset of the data bank should be taken to assemble the reaetion meehanism. ... 

Li, J., Zhao, Z., Kazakov, A., Dreyer, F.L.(2004). An updated comprehensive kinetic model of hydrogen combustion. International Journal of Chemical Kinetics, Vol. 36, pp566-75. 

Borstar is an industrial olefin polymerization plant/technology, which combines different polymerization processes and reactor units, utilizing an advanced catalytic system. In the present work, a detailed model for the dynamic and steady-state simulation of this industrial plant has been developed. A comprehensive kinetic model for the ethylene-1-butene copolymerization over a two-site catalyst was employed to predict the MWD and CCD in the Borstar process. The Sanchez-Lacombe equation of state (S-L EoS) was employed for the thermodynamic properties of the polymerization system and the phase equilibrium calculations in the process units. 

The most common approach to identification of reversibility in chain transfer has been to conduct polymerizations in the presence of potential transfer agents and observe a reduction in both the molecular weight and molecular weight distribution of the oligomer/polymer. A comprehensive kinetic model to predict the effects of reaction variables on the molecular weight behavior in CCTP systems has been reported. This... 

Huang, H., Fairweather, M., Griffiths, J.F., Tomlin, A.S., Brad, R.B. A systematic lumping approach for the reduction of comprehensive kinetic models. Proc. Combust. Inst. 30, 1309-1316(2005)... 

Xiang, Q., Kin, J. S., Lee, Y. Y. A comprehensive kinetic model of dilute-acid hydrolysis of cellulose. Appl Biochem Biotechnol 2003,105-108, 337-352. 

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