Zeolite membrane complex, method of producing zeolite membrane complex, and hydrothermal synthesis apparatus

A zeolite membrane complex, comprising:

• a support which is a longitudinal member having a length of 50 cm or more and has at least one through hole extending in a longitudinal direction;
• and
• a zeolite membrane provided over an inner peripheral surface of said at least one through hole in said support or over an outer peripheral surface of said support, from one end portion of said support in said longitudinal direction to the other end portion thereof,
• wherein among constituent elements of said zeolite membrane except oxygen, an element with the highest percentage is assumed as a main element, and in a case where the concentration of said main element of said zeolite membrane is measured at a plurality of measurement points including respective points on three portions defined by dividing said support into three equal parts in said longitudinal direction, among concentrations of said main element at said plurality of measurement points, a concentration having the maximum absolute value of a difference from an average value of all the concentrations is specified, and an overall evaluation value obtained by dividing the absolute value of the difference of said concentration from said average value by said average value is 15% or less.

A method of producing a zeolite membrane complex, comprising:

• a) preparing a longitudinal support having a length of 50 cm or more;
• and
• b) forming a zeolite membrane on said support by immersing said support in a starting material solution for zeolite membrane formation and performing hydrothermal synthesis,
• wherein while said starting material solution is heated at a predetermined synthesis temperature in said hydrothermal synthesis, the temperature gradient of said starting material solution between respective positions facing one side and the other side of said support in a longitudinal direction ranges from 0.1 to 10° C./m.

A hydrothermal synthesis apparatus, comprising:

• a reaction container which accommodates a longitudinal support having a length of 50 cm or more and is filled with a starting material solution for zeolite membrane formation;
• and
• a heating part for heating said reaction container, to thereby form a zeolite membrane on said support by hydrothermal synthesis,
• wherein while said heating part heats said starting material solution at a predetermined synthesis temperature in said hydrothermal synthesis, the temperature gradient of said starting material solution between respective positions facing one side and the other side of said support in a longitudinal direction ranges from 0.1 to 10° C./m.