Patent ID: 8377838

Claim:
A method for producing a DDR type zeolite membrane having a separation ability of 10 or higher separation coefficient to a mixed gas of carbon dioxide (CO 2 ) and methane (CH 4 ), said method comprising: a membrane formation step of immersing a porous substrate having a DDR type zeolite seed crystal adhered thereon, in a raw material solution containing 1-adamantaneamine, silica (SiO 2 ) and water, and conducting a hydrothermal synthesis of DDR type zeolite to form a 1-adamantaneamine-containing DDR type zeolite membrane on the porous substrate to produce a precursor of DDR type zeolite membrane; and a burning step of heating the precursor at 400° C. or above and at 550° C. or below for 50 hours or longer to burn and remove the 1-adamantaneamine contained in the DDR type zeolite membrane.