Macroporous silicic acids - prepn from silica gel and inorganic salt soln

摘要

The pore of silica gel are filled with an inorganic salt soln., drying and calcining at 300-1500 degrees C. The soln. may be alcoholic or aqs. and the salts have m.p. 300 - 1500 degrees C, e.g. NaC1, KC1, ZnC1, and/or NH4F, or Li salts. The silicic acid pore size is 250-100,000 degrees A. There are very few active sites on the surface of the product so that it is esp. useful as a support in gas chromatography and as a molecular sieve for separating polymers, colloids, enzymes, viruses.