Mitsubishi Plastics, Inc.

Mitsubishi Chemical Corporation

Haijun Chen

Takahiko Takewaki

Takeshi Matsuo

The present invention provides a novel high-silica zeolite having a high molar ration of a tetravalent element (Y) to a trivalent element (X) in terms of oxide. A zeolite, comprising at least a trivalent element X and a tetravalent element Y, wherein a molar ratio n=YO/XOin terms of oxide is 9.5 or more, and the zeolite comprises an RHO-type structure, or comprising at least a trivalent element X and a tetravalent element Y, wherein a molar ratio n=YO/XOin terms of oxide is 9.5 or more, and a characteristic X-ray diffraction pattern. This zeolite is produced by hydrothermal synthesis of a zeolite from an aqueous gel that is prepared by adding a mixed solution comprising a crown ether, an alkali, and water to a solution containing an aluminum atom material, and by then dropwise adding a liquid containing a silicon atom material.

Zeolite, and production method and use therefor

A transition-metal-containing silicoaluminophosphate zeolite having excellent high-temperature hydrothermal durability is easily and efficiently produced. A method for producing a transition-metal-containing zeolite that contains a silicon atom, a phosphorus atom, and an aluminum atom in at least its framework structure includes hydrothermal synthesis using an aqueous gel containing a silicon atom raw material, an aluminum atom raw material, a phosphorus atom raw material, a transition metal raw material, and a polyamine (other than diamines). A transition-metal-containing silicoaluminophosphate zeolite produced by hydrothermal synthesis using a zeolite raw material and the aqueous gel containing the transition metal raw material and the polyamine has excellent high-temperature hydrothermal durability and high catalytic activity.

Transition-metal-containing zeolite

There is provided a water vapor adsorbent for adsorption heat pumps that has high adsorption and desorption performance and high water resistance, such as submersion resistance. The water vapor adsorbent contains a zeolite that contains at least a silicon atom, an aluminum atom, and a phosphorus atom in its framework structure and that has a framework density of 12.0 T/1,000 cubic angstroms or more and 16.0 T/1,000 cubic angstroms or less, wherein the water vapor adsorbent contains a group 11 metal of the periodic table, which constitutes 0.1% to 15% by weight of the zeolite. In the zeolite containing the group 11 metal, an ion of the group 11 metal substitutes for a Bronsted acid site, which promotes a hydrolysis reaction of the zeolite, and decreases the number of Bronsted acid sites of the zeolite, thereby improving the water resistance, such as submersion resistance, of the zeolite.

Growing community of inventors

Yokohama, Japan

Haijun Chen