Performance Evaluation and Characterization of Catalysts

The ultimate task of design and development for industrial catalysts is to invent or update the catalysts that can be applied in special reactions and realize industrial scale manufacture. Most of work involved is carried out in the medium-scale units in the lab. The main work in laboratory is to design chemical compositions of catalyst and to study preparation methods for catalyst. Meanwhile, the evaluation, testing and characterization of the different catalysts should be carried out for comparison and design. The work on design of catalyst is more difficult than that on preparation of catalyst and requires high technology. 

It is hard to find out the most appropriate equipment/method and performance index to measure and assess the quality of catalysts, which is difficult in unified definition and standardization of methods. So far, some methods for evaluating the activities of a few catalysts such as those for catalytic ammonia synthesis and catalytic cracking have been standardized. The evaluation methods are different due to the varieties of catalysts and the experiences of researchers. Sometimes, the technical details of evaluation methods are a part of patent, such as formula and preparation process is confidential. Even then, some basic conceptions and methods for the evaluation and testing of catalysts are still worthy being introduced, which is the main focus of this chapter. 

In general, three main indexes to measure the quality and efficiency of an industrial catalyst are activity (conversion), selectivity and stability. Other performances including mechanical strength, anti-deactivation, geometric physical properties, macro- and micro-physical structure and economic aspect, should also be examined comprehensively, as shown in Table 7.1. 

A catalyst developed successfully should provide three kinds of information of catalysts The chemical composition and structure, the texture organization and mechanical property, and catalytic activity, which are different but connect to each 

Stability (mechanical strength heat-resistant anti-toxic), tolerance of pollution 

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Performance Evaluation and Characterization of Catalysts Table 7.9 Pore volume (Vg) and porosity (6) of catalyst A301 and AllO-2... 

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