Environmental reaction engineering

A review of the state of environmental reaction engineering cannot be accomplished in a chapter of modest length. Rather than attempt a comprehensive review of environmental reaction engineering, therefore, we have chosen to focus here somewhat more narrowly. Specifically, we will discuss several challenging problems in what might be termed atmospheric reaction engineering. 

Catalytic Reaction Engineering for Environmentally Ben%n Chemical Processes... 

Since the first synthesis of ammonia, catalyst development and chemical reaction engineering have been instrumental in the creation of the chemical process industry. As a result, catalytic processes have contributed much to the realization of prosperous civilizaticm. In the future, catalytic processes are expected to fulfill important roles in petroleum refining, diemical processing and environmental preservation. However, at present, many catalytic processes discharge large amounts of byproducts and consume large amounts of auxiliary raw materials. 

The study of the rates of chemical reactions is called kinetics. Chemists study reaction rates for many reasons. To give just one example, Rowland and Molina used kinetic studies to show the destructive potential of CFCs. Kinetic studies are essential to the explorations of reaction mechanisms, because a mechanism can never be determined by calculations alone. Kinetic studies are important in many areas of science, including biochemistry, synthetic chemistry, biology, environmental science, engineering, and geology. The usefulness of chemical kinetics in elucidating mechanisms can be understood by examining the differences in rate behavior of unimolecular and bimolecular elementary reactions. 

We regard the essential aspects of chemical reaction engineering to include multiple reactions, energy management, and catalytic processes so we regard the first seven chapters as the core material in a course. Then the final five chapters consider topics such as environmental, polymer, sohds, biological, and combustion reactions and reactors, subjects that may be considered optional in an introductory course. We recommend that an instmctor attempt to complete the first seven chapters within perhaps 3/4 of a term to allow time to select from these topics and chapters. The final chapter on multiphase reactors is of course very important, but our intent is only to introduce some of the ideas that are important in its design. 

In the presence of a strong reductant, abiotic reductive dechlorination of CPs is catalyzed by the reduced form of Vitamin B12 (Gantzer Wackett, 1991Smith Woods, 1994). These abiotic dechlorinations favor removal of m- and /(-chlorines, which differs substantially from reductive dechlorinations by anaerobic microbial consortia or by the CP-dehalogenating bacteria isolated to date. This indicates that abiotic dechlorinations of CPs are not central reactions in environmental or engineered anaerobic systems. 

Keywords Reactor design Potential environmental impact Chemical reaction engineering Impact analysis... 

Renken, A., Microstructured reactors novel approaches for chemical reaction engineering, in Proceedings of the 27th International Exhibition-Congress on Chemical Engineering, Environmental Protection and Biotechnology, ACHEMA (19-24 May 2003), DECHEMA, Frankfurt, 2003, 13. 

Institute of Chemical Engineering and Environmental Sciences, Department of Chemical Reaction Engineering,... 

Reactive extrusion is a new tool in polymer reaction engineering. From an environmental viewpoint, the need for only small quantities of volatile solvents, and consequent reduced cost, are positive aspects. From an economical point of view, the expensive extrusion equipment is compensated by there being no need to separate the polymer from the solvent The process is largely complicated by the occurrence of various nonlinear effects that may introduce instabilities into the process, these being of thermal, hydrodynamic, and chemical origin. 

Chemical engineering problems in environmental protection usually require a synthesis of thermodynamics, chemical reaction engineering, and transport phenomena, often applied to systems that are not well understood at a fundamental level. An attribute of the revolution in chemical engineering is the opportunity for a deepened understanding of processes at the molecular level, which will have a significant impact on environmental problems. 

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