Abstract: Preparation of so-called "reduced charge" montmorillonite or bentonite pigment from a naturally-occurring crude clay containing dioctahedral montmorillonite by ion-exchanging cations in the clay with hydrogen ions while the clay is in slurry form, filtering, pugging the filter cake with a preselected amount of a neutral or alkaline lithium salt, preferably the oxide, hydroxide or carbonate, and heat treating to collapse the mineral structure.

Abstract: Disclosed is a method for subjecting a finely divided solid to a series of processing steps on a single horizontal vacuum belt filter wherein the processing includes a liquid-solid mass transfer function, such as ion-exchange, carried out by percolation, and this step is followed by at least one step, such as washing, in which rapid passage of a large volume of liquid through the solid takes place. The method is used to ion-exchange zeolitic microspheres in the production of a fluid cracking catalyst.

Abstract: A process for the catalytic cracking of hydrocarbons to produce gasoline wherein the hydrocarbon charge is contacted under fluid cracking conditions with a fluid catalyst composition comprising ion-exchanged synthetic crystalline faujasite and an amorphous alumina-silica residue of caustic leached calcined kaolin clay which had undergone the kaolin exotherm during calcination, the catalyst particles analyzing, on a volatile-free weight basis, at least 90 percent combined SiO.sub.2 and Al.sub.2 O.sub.3 in a SiO.sub.2 /Al.sub.2 O.sub.3 molar ratio within the range of 0.8 to 1.4/1 and less than 3 percent Na.sub.2 O.