Particles featuring gamma alumina
Abstract
Abstract A propensity to form gummy mixtures with water is a troublesome characteristic of a technical grade of boehmite, said power comprising a total ignition loss of about 25 percent, a volatile alcohol content corresponding to less than 1 percent carbon, minor amounts of amorphous alumina and a major amount of alpha mono hydrate. A portion of the technical boehmite is mildly calcined at 400*-500* C. for at least 15 minutes to provide a dehydrated alumina powder, which then mixed with a significantly larger amount of the uncalcined technical grade of boehmite, can be mixed with water for providing a plastic mixture suitable for shaping into catalyst particles. The catalyst particles are calcined above about 600* C. for more than 1 hour in the presence of steam to form attrition resistant particles of gamma alumina having the pore size distribution desirable in certain types of catalysts.
Inventors
- 👤 Edward B Cornelius
- 👤 David W Koester
Bibliographic Details
Claims Analysis
Total Claims: 2References Cited (Backward Citations)
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