Continuous Production of Hydrogen from Sorption-Enhanced Steam Methane Reforming in Two Parallel Fixed-Bed Reactors Operated in a Cyclic Manner

• Published in: Industrial & engineering chemistry research Vol. 45; no. 26; pp. 8788 - 8793
• Main Authors: Li, Zhen-shan, Cai, Ning-sheng, Yang, Jing-biao
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 20-12-2006
• Subjects: Applied sciences; Chemical engineering; Exact sciences and technology; Reactors; Sorption; Reforming; Water vapor; Hydrogen production; Fixed bed reactor
• ISSN: 0888-5885; 1520-5045
• DOI: 10.1021/ie061010x

Hydrogen with purity higher than 90% was produced continuously by sorption-enhanced steam methane reforming reactions in two parallel fixed-bed reactors operated in a cyclic manner. The process involved sorption-enhanced steam methane reforming reactions and a sorbent regeneration reaction. First, through addition of a CO2 sorbent into a reforming reactor, the reactions of reforming, water−gas shift, and CO2 sorption were combined, and more CH4 was expected to convert H2 in one reactor. Second, regeneration of the sorbent was carried out in the other reactor. The hydrogen production and sorbent regeneration processes were carried out simultaneously in the two fixed-bed reactors, operated in a cyclic manner by switching a methane/steam feed and an Ar-containing feed between the two reactors at a fixed feed switchover time. The critical value of the feed switchover time for achieving the production of higher concentrations of hydrogen was investigated and analyzed.