Method for a controlled change of the pore size in solids

摘要

A porous solid such as a zeolite of clay can be degassed to make it suitable as an adsorbent, after which the entrances of the pores are narrowed to a desired size by treating the porous solid with two chemisorbable materials, one of which is diborane. The treatment may be repeated. The purpose of the first such treatment is to make the pore entrances so narrow, that unduly large molecules cannot enter and the smaller ones can, while a later treatment may serve to narrow the pores still further, so that the adsorbed molecules cannot escape.