Abstract: Fine, pure, boehmite alumina crystallites are peptized, partially precipitated and phosphated, hardened, and dried to form a xerogel. The alumina can be impregnated with a chromium compound. The chromium-containing catalyst is activated by calcination. The activated catalyst can be used as a polymerization catalyst to polymerize mono-1-olefins.

Abstract: Fines are reduced in refractory materials by mixing the refractory material with an acid composition in a liquid polar organic compound and thereafter working the mixture until a decrease in volume occurs. The resulting product can be shaped and subjected to conventional finishing treatments. The resulting product exhibits reduced fines and thus is an improved material for use as a catalyst support. The resulting catalyst is of particular utility in the production of film grade ethylene polymer.

Abstract: Fine, pure, boehmite alumina crystallites are peptized, partially precipitated and phosphated, hardened, and dried to form a zerogel. The alumina can be impregnated with a chromium compound. The chromium-containing catalyst is activated by calcination. The activated catalyst can be used as a polymerization catalyst to polymerize mono-1-olefins.

Abstract: A method for producing particles having a controlled particle size from agglomerated material is provided. Agglomerated material is passed through a beater mill and subjected simultaneously to the beating action of a plurality of blades and a vigorous stream of air as the agglomerated material impacts the peripheral screen of the beater mill.

Abstract: Fines are reduced in refractory materials by mixing the refractory material with an acid composition in a liquid polar organic compound and thereafter working the mixture until a decrease in volume occurs. The resulting product can be shaped and subjected to conventional finishing treatments. The resulting product exhibits reduced fines and thus is an improved material for use as a catalyst support. The resulting catalyst is of particular utility in the production of film grade ethylene polymer.

Abstract: Ethylene polymer is particularly suitable for the production of tough film is produced under slurry conditions using a fluorided aluminophosphate support and a reaction temperature within the range of 93.degree. to 107.degree. C. in the presence of hydrogen and a small amount of trialkyl boron cocatalyst wherein said aluminophosphate has a phosphorous to aluminum ratio within the very narrow range of 0.15 to 0.4 and wherein said aluminophosphate carrying chromium catalyst is being activated at a temperature within the range of 482.degree. to 704.degree. C. The resulting film is not only substantially superior to film made from the best of the readily available commercial resins but is also better than film made from polymers using a similar catalyst system without the specific combination of parameters of this invention.

Abstract: Particulate materials such as catalyst or catalyst substrate are slurried and exposed to ultrasonic energy in a rapid attrition treatment.

Abstract: Platinum or other platinum-group metals can be deposited substantially on the surface only of pellets of a refractory catalyst support by impregnation with an aqueous solution of such as hexammonium platinum tetrasulfite. The resulting catalysts contain relatively small total amounts of platinum-group metal positioned primarily at the surface, yet are as highly active as catalysts uniformly impregnated throughout the body of the pellet and containing much larger amounts of platinum-group metal. The catalyst further can contain rhenium.

Abstract: Platinum or other platinum-group metals can be deposited substantially on the surface only of pellets of a refractory catalyst support by impregnation with an aqueous solution of such as hexammonium platinum tetrasulfite. The resulting catalysts contain relatively small total amounts of platinum-group metal positioned primarily at the surface, yet are as highly active as catalysts uniformly impregnated throughout the body of the pellet and containing much larger amounts of platinum-group metal. The catalyst further can contain thenium.