| abstract |
A porous support-zeolite membrane composite obtained by forming a zeolite membrane on an inorganic porous support, wherein the zeolite membrane contains a zeolite having a microporous structure composed of rings which each contain at most 8 oxygen atoms. In the porous support-zeolite membrane composite, the SiO 2 /Al 2 O 3 molar ratio at the surface of the zeolite membrane is larger than that of the zeolite membrane itself by 20 or more, or the water adsorption of the porous support-zeolite membrane composite as determined from the water vapor adsorption isotherm at a relative pressure of 0.8 is at least 82% of the water adsorption of the composite as determined under the same conditions as described above after one-week immersion of the composite in a 90 mass% aqueous acetic acid solution at room temperature. |