Cleaning by depositing of montmorillonite, kaolin clays

摘要

1,221,929. Treatment of clay. ENGLISH CLAYS LOVERING POCHIN & CO. Ltd. 27 Feb., 1968 [28 Feb., 1967], No. 9574/67. Heading C1A. [Also in Divisions B2 and C4] Montmorillonite is removed from a kaolinitic clay by a process which comprises deflocculating an aqueous suspension of the clay, applying shearing forces to the suspension at a solids content of 40-80% by weight, so that the work done is at least 60 horsepower hours per ton, diluting the resulting suspension to a solids content of 10-20% by weight, and centrifuging. The lighter fraction is montmorillonite-rich. If the clay contains up to 4% montmorillonite, the shearing forces are applied to a suspension at a solids content of not less than 55% by wt. For a clay containing 10% montmorillonite a suspension of not greater than 70% is used.