Ammonia separation method and zeolite
AssigneeMitsubishi Chemical Corporation
InventorsManabu Tanaka, Takeshi Matsuo, Takayuki Aoshima
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Abstract
Provided is a method for separating ammonia gas using zeolite membrane having excellent separation stability at a high temperature capable of separating ammonia gas from a mixed gas composed of multiple components including ammonia gas, hydrogen gas, and nitrogen gas to the permeation side with high selectivity and high permeability. Also provided is a method for separating ammonia by selectively permeating ammonia gas from a mixed gas containing at least ammonia gas, hydrogen gas, and nitrogen gas using a zeolite membrane, wherein the ammonia gas concentration in the mixed gas is 1.0% by volume or more.
Claims13
A method for separating ammonia from a mixed gas comprising ammonia gas, hydrogen gas, and nitrogen gas, the method comprising:
- contacting the mixed gas with an aluminosilicate zeolite membrane thereby allowing the ammonia gas to selectively permeate the zeolite membrane and separate from the mixed gas,
- wherein a concentration of the ammonia gas in the mixed gas is 1.0% by volume or more relative to a total volume of the mixed gas.
An aluminosilicate zeolite membrane comprising a zeolite, wherein the zeolite has a molar ratio of N element to Al element from 0.01 to 4, as determined by X-ray photoelectron spectroscopy.
An aluminosilicate zeolite membrane comprising a zeolite, wherein the zeolite has a molar ratio of Si element to Al element from 2.0 to 10, as determined by X-ray photoelectron spectroscopy.
An aluminosilicate zeolite membrane comprising a zeolite, wherein the zeolite has a molar ratio of alkali metal element to Al element from 0.01 to 0.070, as determined by X-ray photoelectron spectroscopy.
A method for separating ammonia from a gas mixture comprising ammonia gas, and hydrogen gas, nitrogen gas, or both, the method comprising:
- contacting the gas mixture with a zeolite membrane composite thereby allowing the ammonia gas to permeate the zeolite membrane composite and separate from the gas mixture,
- wherein the zeolite membrane composite comprises a porous support and an aluminosilicate zeolite membrane comprising a zeolite,
- wherein:
- the aluminosilicate zeolite membrane is deposited on a surface of the porous support;
- and
- a change rate of a thermal expansion coefficient at 300° C. with respect to a thermal expansion coefficient at 30° C. of the zeolite is equal to or within ±0.25% and a change rate of a thermal expansion coefficient at 400° C. with respect to the thermal expansion coefficient at 30° C. of the zeolite is equal to or within ±0.35%.
Dependencies are inferred from the claim text.