Abstract: A structured kaolinitic pigment having improved physical and optical characteristics when incorporated as a filler in paper. The pigment is also useful in paper coating applications. The pigment consists of porous aggregates of kaolin particles which are chemically bonded together. The pigment may be produced by chemically reacting a particulate kaolin with a metal chloride, such as silicon tetrachloride. The process is conducted under conditions such that the kaolinite structure is not impaired.

Abstract: A method for chlorinating a clay mineral starting composition to produce reactive chloride intermediates, comprising: reacting said composition in substantially dry particulate form with gaseous SiCl.sub.4 to activate the surface of said composition, thereby forming said reactive chloride intermediate, said reaction being conducted at temperatures below that at which volatilization or dehydration of the starting composition will occur. The resulting compounds are highly reactive intermediates, which can then be functionalized by reaction with a large group of organics, or organic derivatives.

Abstract: A method for chlorinating the surface of a layered lattice silicate to produce a reactive chloride intermediate. The layered lattice silicate is reacted in substantially dry particulate form with a reactant system capable of forming bound chloride moieties at its surface, to form the said chloride thereof, the reaction being conducted at temperatures below that which would otherwise substantially alter the starting composition.

Abstract: A fluidized bed apparatus is provided which comprises (a) a fluidized bed container having gaseous fluidization agent intake means and discharge means; (b) gaseous fluidization agent distributor means comprising a distributor-separator plate arranged intermediate said gaseous agent intake and discharge means that is adapted to receive a mass of solid particles and substantially separate said particles from said gaseous agent intake means and has a plurality of parts therethrough spaced over substantially the entire surface thereof which have means for controlling the velocity and dispersion of a gaseous fluidization agent passing between said intake means and said discharge means; and (c) vibrating means for vibrating said container. Preferably, said container includes filter means intermediate said distributor-separator plate and said gaseous agent discharge means.