Abstract: An in situ process for making improved zeolitic fluid cracking catalysts by spray drying a mixture of (i) hydrous kaolin and/or metakaolin, and (ii) calcined aluminum source, said calcined aluminum source being derived from a pulverized, ultrafine kaolin, calcining the resulting microspheres to convert hydrous kaolin to metakaolin, and reacting microspheres composed of a mixture of metakaolin and calcined aluminum source with an alkaline sodium silicate solution. The weight percent of metakaolin in the calcined microspheres is greater than the calcined aluminum source content.

Abstract: An in situ process for making improved zeolitic fluid cracking catalysts by spray drying a mixture of (i) hydrous kaolin and/or metakaolin, and (ii) calcined aluminum source, said calcined aluminum source being derived from a pulverized, ultrafine kaolin, calcining the resulting microspheres to convert hydrous kaolin to metakaolin, and reacting microspheres composed of a mixture of metakaolin and calcined aluminum source with an alkaline sodium silicate solution. The weight percent of metakaolin in the calcined microspheres is greater than the calcined aluminum source content.

Abstract: A method for reducing the abrasion of a silica-containing calcined kaolin pigment by the controlled leaching of silica from the pigment, preferably by the use of a caustic solution to dissolve the silica out of the calcined kaolin. In another aspect of the invention, the brightness, opacity, or both of a calcined kaolin is increased by increasing the fineness of the kaolin feed supplied to the calciner. The combination of these methods results in the production of a calcined kaolin with low abrasion and high brightness and opacity. Another aspect of the invention concerns an improved method of filtration of dilatent materials such as the leached calcined clay.

Abstract: This invention pertains to the use of a combination of polyvalent cations, clay dispersant and high molecular weight anionic polymer to preferentially remove colloidal fines (slimes) from a kaolin slurry, leaving the remainder of the kaolin in the slurry in the form of a coherent gelatinous mass.

Abstract: A process for filtering kaolin clay slurries in the presence of a filter aid which increases the percent solids in the filter cake, decreases the product solids in the waste filtrate, increases the rate of filtration, and yet does not interfere with redispersal of the filter cake after filtration. The process utilizes high molecular weight, highly anionic polyacrylic acid homopolymers or copolymers, or water soluble salts thereof, as filter aids for thickening and dewatering kaolin clay slurries. The flocculated clay may be redispersed after the separation process by normal means, such as the addition of low molecular weight anionic polymers with mixing.

Abstract: Paper coating pigments comprising a product obtained by the controlled mechanical delamination of kaolin particles. The pigments provide improved opacification, brightness, printing properties and gloss compared to conventional delaminated kaolin pigments. The pigment of the invention is particularly useful for coating light weight printed paper and provides a unique combination of high opacity, brightness and gloss not available when using other kaolin pigments. The novel pigment is specifically designed to replace plastic pigments and (or) titanium dioxide in coating formulations while maintaining or improving desired paper properties.

Abstract: Described is a process for separating a mixture of finely divided minerals into constituents thereof. In particular, the invention relates to a procedure for effecting such separation by a novel selective flocculation technique wherein a dispersed aqueous pulp containing the mixture of minerals is preconditioned for selective flocculation with an anionic polymer by addition of both a fatty acid such as oleic acid and source of polyvalent cation such as calcium chloride. The fatty acid and cation of the salt selectively coat the component of the mixture that is subsequently flocculated with the anionic polymer. A polyacrylate salt dispersant is preferably used in the process. The invention is especially adapted to the separation of colored titaniferous impurities from kaolin clay in which case both a white purified kaolin product and a strongly flocculated dun-colored titania/kaolin mixture are recovered and then dispersed producing a material useful as a paper coating pigment.

Abstract: This invention relates to paper filling pigments comprising novel mechanically delaminated kaolin particles having controlled narrow particle size distribution and shape. The pigments provide improved opacification compared to conventional and engineered kaolin particles in fine paper making.

Abstract: A selective flocculation process that uses a mixture of dispersants including soda ash to disperse a slimed ore pulp prior to conditioning with a fatty acid, salt and then a polymeric flocculating agent.

Abstract: Described is a process for separating a mixture of finely divided minerals into constituents thereof. In particular, the invention relates to a procedure for effecting such separation by a novel selective flocculation technique wherein a dispersed aqueous pulp containing the mixture of minerals is preconditioned for selective flocculation with an anionic polymer by addition of both a fatty acid such as oleic acid and source of polyvalent cation such as calcium chloride. The fatty acid and cation of the salt selectively coat the component of the mixture that is subsequently flocculated with the anionic polymer. A polyacrylate salt dispersant is preferably used in the process. The invention is especially adapted to the separation of colored titaniferous impurities from kaolin clay in which case both a white purified kaolin product and a strongly flocculated dun-colored titania/kaolin mixture are recovered and then dispersed producing a material useful as a paper coating pigment.

Abstract: This invention relates to a process for separating a mixture of finely divided minerals into constituents thereof. In particular, the invention relates to a procedure for effecting such separation by a novel selective flocculation technique wherein a dispersed aqueous pulp containing the mixture of minerals is preconditioned for selective flocculation with an anionic polymer by addition of both a fatty acid such as oleic acid and source of polyvalent cation such as calcium chloride. The fatty acid and cation of the salt selectively coat the component of the mixture that is subsequently flocculated with the anionic polymer. A polyacrylate salt dispersant is preferably used in the process. The invention is especially adapted to the separation of colored titaniferous impurities from kaolin clay.

Abstract: Paper coating pigments comprising mechanically delaminated kaolin particles. The pigments possess the opacification, smoothness and printability advantages of conventional delaminated kaolin pigments but have desirably low viscosity and gloss not characteristic of conventional delaminated kaolin pigments. Crude kaolins of specified physical characteristics for production of these pigments by controlled delamination.

Abstract: A process for reacting metallic iron with sulfur dioxide (SO.sub.2) gas in the presence of water and bleachable matter, especially iron-contaminated kaolin clay, whereby the kaolin or the like is bleached in situ and the viscosity of the kaolin is less than it would be if bleached in a conventional manner.

Abstract: An improved method for improving the brightness of clay of the type that is capable of being bleached by an oxidative reagent such as Georgia gray kaolin. Such clay, in the form of a dispersed slurry, is treated with a combination of sodium silicate, sodium hypochlorite and ozone, most preferably followed by magnetic purification and a reduction bleach. Sodium hypochlorite is added shortly before ozonation.

Abstract: Pigments in a form for bulk shipment are prepared by kneading dry pigment particles with a limited amount of water or an aqueous slurry of pigment particles to form dough-like, dust-free agglomerates which are shipped without subsequent drying and/or compaction.

Abstract: Paper coating pigments comprising mechanically delaminated kaolin particles. The pigments possess the opacification, smoothness and printability advantages of conventional delaminated kaolin pigments but have desirably low viscosity and gloss not characteristic of conventional delaminated kaolin pigments.

Abstract: A process for reacting metallic iron with sulfur dioxide (SO.sub.2) gas in the presence of water and bleachable matter, especially iron-contaminated kaolin clay, whereby the kaolin or the like is bleached in situ.

Abstract: A low-abrasion calcined kaolin opacifying pigment composed of particles in the size range of about 70 to 84% by weight finer than 2 microns and having a color defined by Hunter Trisitimulus values of "L" within the range of 92 to 94, "a" within the range of .sup.+ 1.0 to .sup.+ 2.2 and "b" within the range of .sup.+6.4 to .sup.+ 7.5. The pigment is produced by novel wet processing including high solids degritting of a high iron, high titania content Tertiary kaolin without conventional fractionation, bleaching and dewatering to isolate a fine particle size fraction, followed by spray drying, pulverization, calcination and repulverization.

Abstract: A process which is especially useful for effecting magnetic separation of magnetically attractable impurities from an aqueous clay slurry or suspension includes passing the suspension through a porous, ferromagnetic matrix while applying a magnetic field to the matrix, on which impurities are collected, and thereafter regenerating the matrix by flushing collected impurities therefrom with a flush liquid, e.g., water. The improvement comprises, after discontinuing the passage of the suspension through the matrix, but before passing flush liquid therethrough, admitting a pressurized gas, e.g., compressed air, into the separator to displace suspension retained therein, and recovering the displaced suspension. In addition, flush liquid retained in the matrix after the flushing step may be displaced therefrom by the compressed air. By displacing the retained suspension from the matrix with, e.g., compressed air, instead of a flush liquid, e.g.

Abstract: A process for the wet processing of kaolin clay which includes a step for physically removing discrete particles of colored impurities by high gradient magnetic separation (HGMS) in which all processing steps including HGMS are carried out with the feed clay slurry at high solids, above 50%, and the magnetically purified clay slurry is also recovered at high solids, above 50%. A feature of the invention is that the HGMS unit is operated in a novel manner such as to avoid the dilution of the magnetically purified clay slurry with water during all stages of HGMS treatment without adverse effect on the yield of magnetically purified clay.