A process for the production of crack-free semi-permeable inorganic membranes.

摘要

The membranes are coated on a microporous sintered support of an inorganic oxide and can be used up to a temperature of 900 DEG C while retaining their small pore diameters, e.g. for gas separation. …The support having a typical pore-size of from 0.10 mu to 0.50 mu is submerged during 1 to 5 sec.. in a sol containing 0.01% to 25% by weight Boehmite with a preferred particle-size of 3nm to 2 mu , to obtain a membrane layer up to 20 mu . The submerged support is thereafter dried out and heated to a temperature of at least 390 DEG C and the intermediate product may be heated thereafter up to 1500 DEG C. Heating at a temperature of about 500 DEG C during 24 hours is preferred. The sol contains by preference HNO3 or 0.01 to 0.20 mol HClO4 per mol Boehmite and the microporous support is preferred to be d-Al2O3.