Engineering chemical reaction

In chemical reaction engineering, data and models obtained from applied chemical kinetics are used to design, optimize and control a chemical reactor by taking into account the feedstock specifications and the technical and economic constraints (Table 2). Whereas, in applied 

The fundamentals of chemical reaction engineering can be found in many books [23-31]. See also ref. 237. 

The major objective of chemical reaction engineering is the analysis and design of equipment for carrying out desirable chemical reactions, i.e. chemical reactors. 

The essential feature in chemical reactor analysis and design is the formulation of conservation equations for mass and energy for the chosen type of reactor. These equations can be either algebraic or differential and their solution gives the extent of the reaction. 

This chapter gives an introduction to the subject of chemical reaction engineering. The first part introduces basic definitions and concepts of chemical reaction engineering and chemical kinetics and the importance of mass and heat transfer to the overall chemical reaction rate. In the second part, the basic concepts of chemical reactor design are covered, including steady-state models and their use in the development 

Another classification of chemical reactors is according to the phases being present, either single phase or multiphase reactors. Examples of multiphase reactors are gas liquid, liquid-liquid, gas solid or liquid solid catalytic reactors. In the last category, all reactants and products are in the same phase, but the reaction is catalysed by a solid catalyst. Another group is gas liquid solid reactors, where one reactant is in the gas phase, another in the liquid phase and the reaction is catalysed by a solid catalyst. In multiphase reactors, in order for the reaction to occur, components have to diffuse from one phase to another. These mass transfer processes influence and determine, in combination with the chemical kinetics, the overall reaction rate, i.e. how fast the chemical reaction takes place. This interaction between mass transfer and chemical kinetics is very important in chemical reaction engineering. Since chemical reactions either produce or consume heat, heat removal is also very important. Heat transfer processes determine the reaction temperature and, hence, influence the reaction rate. 

Finally, chemical reactors can be classified according to the mode of heat removal. We can have either isothermal or non-isothermal reactors, a sub-category of which is adiabatic reactors. Often it is desirable to use the heat released by an exothermic reaction for an endothermic reaction, in order to achieve higher heat integration. 

In this chapter emphasis is placed on chemical reaction engineering and the reactor design, although separation steps for product purification (examined in Section 3.3) are also important for the plant design (and in many cases have great visual impact, see figure below). 

Syngas production by partial oxidation of heavy oil with C02-wash and pressure swing adsorption, Oberhausen, Germany. Courtesy of Linde Engineering, Germany. 

1 Main Aspects and Basic Definitions of Chemical Reaction Engineering 

What are the thermodynamic constraints of a reaction, and what temperature and pressure should be apphed to maximize conversion and product yield(s)  

What is the size of reactor or amount of catalyst needed for a certain degree of reaction progress Which processes determine the effective reaction rate What are the differences between homogeneous, catalytic and gas-solid reactions All these questions address the kinetics, and the equations for various reaction types will be derived, including the inspection of mass and heat transfer resistances. 

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Levenspiel, O., Chemical Reaction Engineering, 2d ed., Wiley, New York, 1972. 

M. Koukohk and J. Matek, Proceedings of the 4th European Symposium on Chemical Reaction Engineering, Bmssels, 1968, pp. 347—359. 

Early ia the development of chemical reaction engineering, reactants and products were treated as existing ia single homogeneous phases or several discrete phases. The technology has evolved iato viewing reactants and products as residing ia interdependent environments, a most important factor for multiphase reactors which are the most common types encountered. 

M. E. Edwards, Chemical Reaction Engineering of Polymer Processing Reaction Injection Moulding Inst. Chem. Eng. Symp. Ser. 8(87), 783—796 (1984). 

Cropley, J. B. Heuristic Approach to Complex Kinetics, pp. 292-302 in Chemical Reaction Engineering—Houston, ACS Symposium Series 65, American Chemical Society, Washington, DC (1978). 

In turbulent flow, axial mixing is usually described in terms of turbulent diffusion or dispersion coefficients, from which cumulative residence time distribution functions can be computed. Davies (Turbulence Phenomena, Academic, New York, 1972, p. 93), gives Di = l.OlvRe for the longitudinal dispersion coefficient. Levenspiel (Chemical Reaction Engineering, 2d ed., Wiley, New York, 1972, pp. 253-278) discusses the relations among various residence time distribution functions, and the relation between dispersion coefficient and residence time distribution. 

Brotz, W. 1965, Fundamentals of Chemical Reaction Engineering. Addison-Wesley, Reading, MA... 

Fogler, H. S. 1998, Elements of Chemical Reaction Engineering 2nd Edition, Prentice Hall, Inc., Englewood Cliffs, NJ... 

Reproduced from Proceedings of the Fifth European and Second Int. Symposium on Chemical Reaction Engineering, B, 8-27-38, 1972 Elsevier. 

Berty, J.M., J.H. Bricker, S.W. Clark, R.D. Dean and T.J. McGovern, 1972, Proceedings of the Fifth European/Second International Symposium on chemical Reaction Engineering, Amsterdam, 2-A May, Elsevier Publishing. 

Cropley, J.B., 1978, Chemical Reaction Engineering, paper 24 in ACS Symposium Series 65, pp. 292-302. 

First European Symposium on chemical Engineering, 1957, Chemical Reaction Engineering, Pergamon Press, Amsterdam, New York. 

At the First European Symposium on Chemical Engineering, Amsterdam, (1957) the definition for Chemical Reaction Engineering was accepted as ... 

Chemical reaction engineering is part of chemical engineering in general. It aims at controlling the chemical conversion on a technical scale and will ultimately lead to appropriate and successful reactor design. An important part is played by various factors, such as flow phenomena, mass and heat transfer, and reaction kinetics. It will be clear that in the first place it is necessary to know these factors separately. 

Octave Levenspiel "Chemical Reaction Engineering," John Wiley Sons, New York, 1962. 

Walas, S. M., Chemical Reaction Engineering Handbook of Solved Problems, Gordon and Breaeh Publishers, 1996. 

Missen, R. W., Mims, C. A., and Saville, B. A., Introduction to Chemical Reaction Engineering and Kinetics, John Wiley Sons, 1999. 

Safety in Chemical Reaction Engineering 911 Other factors that are responsible for exothermic incidents are ... 

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