Extrusion and acid treatment of clay to improve filtration properties

摘要

A method of extruding clay and then treating the clay with acid to beneficiate the clay for increased capacity of filtration of oil- soluble colorant compounds from oil. The clay is first extruded through one or more die openings to align some of the clay platelets and to form the clay into cylindrical pellets. The extruded clay pellets are then acid treated, either before or after grinding, in an aqueous acid solution to form an acid slurry of the clay. The acid slurry of the clay is agitated for a time sufficient and at a temperature sufficient so that the acid reacts with a portion of the clay and, thereafter, the acid treated clay is separated from the acid solution; the clay then is washed to remove most of the acid solution from the clay; filtered and thereafter dried.