Reactor engineering aspects, chemical

Dente and Ranzi (in Albright et al., eds.. Pyrolysis Theory and Industrial Practice, Academic Press, 1983, pp. 133-175) Mathematical modehng of hydrocarbon pyrolysis reactions Shah and Sharma (in Carberry and Varma, eds.. Chemical Reaction and Reaction Engineering Handbook, Dekker, 1987, pp. 713-721) Hydroxylamine phosphate manufacture in a slurry reactor Some aspects of a kinetic model of methanol synthesis are described in the first example, which is followed by a second example that describes coping with the multiphcity of reactants and reactions of some petroleum conversion processes. Then two somewhat simph-fied industrial examples are worked out in detail mild thermal cracking and production of styrene. Even these calculations are impractical without a computer. The basic data and mathematics and some of the results are presented. 

Nitric acid is one of the three major acids of the modem chemical industiy and has been known as a corrosive solvent for metals since alchemical times in the thirteenth centuiy. " " It is now invariably made by the catalytic oxidation of ammonia under conditions which promote the formation of NO rather than the thermodynamically more favoured products N2 or N2O (p. 423). The NO is then further oxidized to NO2 and the gases absorbed in water to yield a concentrated aqueous solution of the acid. The vast scale of production requires the optimization of all the reaction conditions and present-day operations are based on the intricate interaction of fundamental thermodynamics, modem catalyst technology, advanced reactor design, and chemical engineering aspects of process control (see Panel). Production in the USA alone now exceeds 7 million tonnes annually, of which the greater part is used to produce nitrates for fertilizers, explosives and other purposes (see Panel). 

Froment and Bischoff [5] and Rase [6] cover, in addition, many of the more engineering aspects of the design of chemical reactors. 

R.M. Koros, Engineering aspects of trickle-bed reactors, in H.I. dc Lasa (Ed.), Chemical Reactor Design and Technology, M. Nijhoff Publ., Dordrecht, 1986, pp.579-630. 

Transport phenomena in heterogeneous catalysis This section will not attempt to cover the more technical aspects of chemical reactor engineering. 

This chapter reviews some of the main topics involved in the design and modeling of solar photocatalytic reactors, with particular emphasis on the authors research experience. Solar photons are source of energy that initiates photocatalytic degradation. Thus, proper consideration of radiative processes is key to address this subject. The determination of the directional and spectral characteristics of solar UV radiation, the interaction of the catalyst with radiation inside reaction spaces, the optical design of solar collectors, and the optical properties of the materials involved are all subjects where these concepts are necessary. Therefore, developments in this area should be solidly grounded on the fields of solar collector optics and radiative transfer, besides the more traditional chemical engineering aspects involved. This requires a multidisciplinary approach. 

To simulate the effects of reaction kinetics, mass transfer, and flow pattern on homogeneously catalyzed gas-liquid reactions, a bubble column model is described [29, 30], Numerical solutions for the description of mass transfer accompanied by single or parallel reversible chemical reactions are known [31]. Engineering aspects of dispersion, mass transfer, and chemical reaction in multiphase contactors [32], and detailed analyses of the reaction kinetics of some new homogeneously catalyzed reactions have been recently presented, for instance, for polybutadiene functionalization by hydroformylation in the liquid phase [33], car-bonylation of 1,4-butanediol diacetate [34] and hydrogenation of cw-1,4-polybutadiene and acrylonitrile-butadiene copolymers, respectively [10], which can be used to develop design equations for different reactors. 

Surface tension is an important property in the study of physics and chemistry at free surfaces as it affects the transfer rates of vapor absorption at the vapor-liquid interface. Such data are of importance to scientists, engineers, and practitioners in many fields such as chemical process and reactor engineering, flow and transport in porous media, materials selection and engineering, biomedical and biochemical engineering, electronic and electrical engineering, etc. The surface of a liquid is not only interesting for the fundamental aspects but also for its relevance in environmental problems, biological phenomena, and industrial applications. 

M.M.G. Senden, S.T. Sie, M.E.M. Post and J. Ansorge. Engineering Aspects of the Conversion of Natural Gas into Middle Distillates , HJ de Lasa et al (eds.). Chemical Reactor Technology for Environmentally Safe Reactors and Products, pp.227-247 (1992)... 

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