THE SEPARATION OF GASEOUS-MIXTURES WITH COMPOSITE MICROPORE GLASS MEMBRANES AT HIGH-TEMPERATURE

Separation of gaseous mixtures was carried out up to 773 K using composite microporous glass membranes coated on the surface of porous ceramic tubing. The composition of the metal alkoxide solution used in the coating process was Si(OC2H5)4:27.9; C2H5OH:42.0; H2O:26.2; HCl:0.3 and H3BO3:3.6wt%. With the ceramic tubing supplied by TOTO Co., Ltd, much thinner microporous glass membranes can be made, because five coating cycles were enough to obtain a coating free of cracks, compared with at least seven cycles for TDK Co., Ltd material. The membrane can permeate only H2O from the thermochemical reaction gas mixture of H-2 and H2O, at the flux rate of 37 kg (m2 day)-1 at a trans-membrane pressure of 0. 196 MPa and at 773 K.