Process for producing a poly(alumino-silicate) and product prepared by this process

摘要

In a process for preparing particulate, porous, water-insoluble amorphous poly(alumino-silicate) having a Si/AI gram-atomic ratio of about 1:1 to 10:1, a pore volume of greater than 0.5 ml/g, an average pore diameter of 50 to 200 A and a surface area of 200 to 600 m2/g by mixing an aqueous solution of an appropriate aluminate and an aqueous solution of an appropriate silicate, allowing the aluminate and silicate in the resultant mixture to polymerize to poly(alumino-silicate), freezing the mixture and thereafter isolating, washing, drying and recovering particulate poly(alumino-silicate) therefrom, said process characterized in that:(a) the amounts, respectively, of aluminate and silicate, calculated as Al2O3 and SiO2, are such that the total amount thereof in the mixture is about4 to 25 weight %ofthe mixture, such that the Si/AI gram-atomic ratio in the mixture is about 1:1 to 10:1, and such that the amount, in the mixture, of at least one water-soluble compound which is precipitable from the mixture at -10 to -100°C and which is inert to the aluminate, silicate and poly(alumino-silicate) is about 25 to 160 weight % based on the combined weights of aluminate and silicate, calculated as Al2O3 and Si02; and(b) the mixture is cooled to about -10 to -100°C until it is frozen, to separate substantially all of the chemically unbound water as substantially pure ice and to precipitate water-soluble compound within the pores of the poly(alumino-silicate) particles being formed.