Aluminosilicate acid catalysts, dehydration

Structural and Mechanistic Aspects of the Dehydration of Isomeric Butyl Alcohols over Porous Aluminosilicate Acid Catalysts... 

Zamaraev, K.I. and Thomas, J.M. Structural and mechanistic aspects of the dehydration of isomeric butyl alcohols over porous aluminosilicate acid catalysts. Adv. Catal. 1996, 41, 335-358. 

We have also investigated the properties of several of our nanostructured catalysts as solid acids in reactions such as the dehydration of alcohols and transesterification reactions [99]. One of the best examples of atomically dispersed solid acid catalysts is aluminosilicates [100]. When aluminium is substituted into silicate frameworks and remains isolated from other A1 centers it can behave as a strong acid site [101]. 

Over the past five years, we and our colleagues have undertaken an extensive study of the acid-catalyzed dehydration of the four isomeric butyl alcohols. In so doing, we compared the performance of crystalline, molecular-sieve acid catalysts (HZSM-5) in a range of crystal sizes (so as to vary diffusion path and active-site concentration) with that of amorphous aluminosilicate (AAS) gels in which the pore size is significantly larger. Our results, which permit the... 

Hydration and dehydration employ catalysts that have a strong affinity for water. Alumina is the principal catalyst, but also used are aluminosilicates, metal salts, and phosphoric acid or its metal salts on carriers and cation exchange resins. 

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