Page 147 - Principles of Catalyst Development

CATALYST CHARACTERIZ)~ TION

How They Are Tested

7.1. PRELIMINARY REMARKS

Characterization of the catalyst is necessary at every stage of development.
Critical parameters are measured not only to check the effectiveness of each
operation but also to provide specifications for future products. Prepar-
ational procedures can be properly assessed and corrections made only if
guidelines to the properties are available. Product quality in commercial
production is facilitated with appropriate testing, and the first step in any
diagnosis of process problems is to measure changes that have occurred. It
is vital that accepted techniques for determining these characteristics be
established as an adjunct to research design, preparation, testing, and
manufacture.
In this chapter, we examine current methods for measuring those
properties of the catalyst relating to plant performance. These are classified
as bulk, particle, and surface properties, including such factors as composi-
tion, structure, mechanical properties, surface area, dispersion, and acid-
ity.(191) Although these measurements also enter into rest:arch, specialized
techniques in scientific studies are not included, nor do we treat methods
that investigate adsorbates, unless they are part of adsorbent characteriz-
ation.
With this approach, we describe applicability of each method, including
capabilities and limitations. Most workers in catalyst development are not
necessarily expert in analytical procedures. The techniques described are
usually available within the facilities of most companies or from outside
testing laboratories. For this reason, details of instrumentation and
methodology have been minimized in order to concentrate on what should
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