Patents
The invention relates to a process of making a single-layer ultrafiltration membrane inside clay-alumina porous tubular support instead of multiple-layer coating and a process thereof to make single-layer coating having pore sizes less than 20 nm and at most 50 nm is disclosed. A mesoporous membrane layer having an average pore diameter smaller than 50 nm is formed on the porous tubular support made of a mixture of clay and alumina with thickness from 1.0 mm to 3 mm; OD from 9 mm to 35 mm; ID from 6 mm to 25 mm; pore size from 0.5 to 2.0 micro m. Ceramic slurry made of individual nanosized powder consisting of Zr02 and/or Ab03 boehmite is deposited inside the porous tubular support, dried in air, followed by firing to a temperature of at least 400 °C and at most 800 °C to form an ultrafiltration ceramic membrane having an average pore diameter in the range of 18 nm and less than 50 nm