US 12,275,639 B2
Method for preparing hydrogen gas
Byeong Soo Shin, Uiwang-si (KR); Kyung Moon Lee, Uiwang-si (KR); Young Jin Cho, Gimhae-si (KR); Yong Ha Park, Suwon-si (KR); Hoon Mo Park, Seongnam-si (KR); and Dong Hoon Nam, Suwon-si (KR)
Assigned to HYUNDAI MOTOR COMPANY, Seoul (KR); and KIA CORPORATION, Seoul (KR)
Filed by HYUNDAI MOTOR COMPANY, Seoul (KR); and Kia Corporation, Seoul (KR)
Filed on Jul. 26, 2022, as Appl. No. 17/874,248.
Claims priority of application No. 10-2022-0029659 (KR), filed on Mar. 8, 2022.
Prior Publication US 2023/0286800 A1, Sep. 14, 2023
Int. Cl. B01D 53/04 (2006.01); B01D 53/047 (2006.01); C01B 3/04 (2006.01); C01B 3/56 (2006.01)
CPC C01B 3/56 (2013.01) [B01D 53/0462 (2013.01); B01D 53/047 (2013.01); C01B 3/047 (2013.01); B01D 2253/102 (2013.01); B01D 2253/108 (2013.01); B01D 2257/102 (2013.01); B01D 2257/404 (2013.01); B01D 2257/406 (2013.01); B01D 2259/403 (2013.01); C01B 2203/0277 (2013.01); C01B 2203/042 (2013.01); C01B 2203/08 (2013.01); C01B 2203/1205 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A method for preparing hydrogen gas, the method comprising:
a decomposition step of decomposing ammonia-containing gas to produce decomposition-product gas, which contains nitrogen (N2), hydrogen (H2), and undecomposed ammonia, and exhaust gas;
a first adsorption step of adsorbing and removing the undecomposed ammonia contained in the decomposition-product gas by a first adsorbent to produce first product gas containing nitrogen (N2) and hydrogen (H2);
a second adsorption step of adsorbing and removing the nitrogen (N2) contained in the first product gas by a second adsorbent to produce higher-purity hydrogen (H2);
a first regeneration step of regenerating the second adsorbent by desorbing the nitrogen (N2) adsorbed to the second adsorbent while generating second off gas containing nitrogen (N2) and hydrogen (H2); and
a third heat-exchange step of heat-exchanging the exhaust gas transferred from the decomposition step and at least a portion of the second off gas transferred from the first regeneration step; and
a second regeneration step of regenerating the first adsorbent after the first adsorption step by transferring, to the first adsorbent, the exhaust gas and the at least a portion of the second off gas, which are heat-exchanged in the third heat-exchange step and serve as heating-desorbing gas, and a remainder of the second off gas, which is transferred from the first regeneration step and serves as cooling-cleaning gas.