Page 107 - Principles of Catalyst Development
P. 107

CATALYST  PREPARATION

            How  They Are Made








            6.1.  INTRODUCTION

            Although some degree  of catalytic activity is  found  in  any given  material,
            successful preparations proceed through a series of mysterious steps justify-
            ing the judgment "black art."  Indeed,  it  was  this  very  fact  that  prompted
            the following  quotation from  Ranei  I54 ):

                 It is  in  the  preparation  of catalysts that the  chemist  is  most  likely  to  revert  to
                 type  and to employ alchemical  methods. The work  should be approached with
                 humility  and  supplication  and  the  production  of a  good  catalyst  received  with
                 rejoicing  and thanksgiving.

                In  this  chapter,  we  find  that  catalyst  preparational  methods  are  not
            always  magical  but  that  some  of the  elements  mentioned  by  Raney  are
            indeed  necessary  for  success.  Catalysts  are  considered  in  the  order  listed
            in Table 6.1.



            6.2.  SINGLE  ACTIVE  COMPONENTS  AND  SUPPORTS

                Single oxide active components and supports are usually prepared with
            high surface area and porosity. Similar techniques apply in the production
            of both, but the major use of these materials is  for supports. (53)  Procedures
            used  are those found  in the  preparation of colloidal hydrous oxides,  with
            variations  inherent to  each  type.(155)  The  preparational  steps  are  given  in
            Fig. 6.1.
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