US Patent 7819944 Method of dehydration, dehydrating apparatus, and membrane reactor

A dehydration method by which water is selectively separated from a water-containing mixture 31 with a separation membrane. The separation membrane is a DDR type zeolite membrane 2. The dehydration method includes bringing the mixture 31 into contact with one side of the DDR type zeolite membrane 2 and causing a pressure difference between that side of the DDR type zeolite membrane 2 which is in contact with the mixture and the other side of the DDR type zeolite membrane 2 to thereby cause the water to selectively permeate and separate out. By the dehydration method, water can be selectively separated from a water-containing mixture without the need of a high energy cost. The separation membrane has excellent acid resistance.