Hydrogen Production by Sorption‐Enhanced Steam Glycerol Reforming: Sorption Kinetics and Reactor Simulation

Abstract

in Wiley Online Library (wileyonlinelibrary.com).Sorption-enhanced glycerol reforming, an integrated process involving glycerol catalytic steam reforming and in situ CO 2 removal, offers a promising alternative for single-stage hydrogen production with high purity, reducing the abundant glycerol by-product streams. This work investigates this process in a fixed-bed reactor, via a two-scale, nonisothermal, unsteady-state model, highlighting the effect of key operating parameters on the process performance. CO 2 adsorption kinetics was investigated experimentally and described by a mathematical reaction-rate model. The integrated process presents an opportunity to improve the economics of green hydrogen production via an enhanced thermal efficiency process, the exothermic CO 2 adsorption providing the heat to endothermic steam glycerol reforming, while reducing the capital cost by removing the processing steps required for subsequently CO 2 separation. The operational time of producing high-purity hydrogen can be enhanced by increasing the adsorbent/catalyst volume ratio, by adding steam to the reaction system and by increasing the inlet reactor temperature.

High temperature CO2 sorbents and their application for hydrogen production by sorption enhanced steam reforming process

“…In the presence of CaO as the CO 2 sorbent, it was found that the in-situ CO 2 removal resulted in a significant enhancement of H 2 production and thermal efficiency as well as an important reduction of CO concentration [209,[217][218][219]. Chen et al [220] performed thermodynamic analyses on the SESGR process based on the principle of Gibbs free energy minimization for chemical reactions.…”

Solid sorbents for in-situ CO 2 removal during sorption-enhanced steam reforming process: A review

“…With the presence of steam in the gas mixture, MgO-based sorbents in the carbonation reaction could significantly increase the reactivity and capacity [73]. MgCO 3 can be formed in the presence of H 2 O due to the reactions of (4) and (5). And the used sorbent can be regenerated into Mg(OH) 2 (shown as (6)) at relatively low temperatures:…”

“…In addition, it is a low-cost hydrogen production due to reducing the number of processing steps required for subsequently separating CO 2 and decreasing the reaction temperatures for energy usage [1][2][3][4][5][6]. In general, SERP concept can be accomplished in different types of reactor configurations including (a) the interconnected fluidized-bed reactor; (b) alternating fixed-bed reactor; and (c) rotating reactor.…”

“…extensive studies on novel systems for hydrogen production have been carried out as SERP with in-situ CO 2 removal, which has been considered to change the normal equilibrium limits of shift reactions for producing high-purity hydrogen and increasing hydrocarbons conversion [1][2][3][4][5][6][7][8][9][10][11][12][13]. In addition, it is a low-cost hydrogen production due to reducing the number of processing steps required for subsequently separating CO 2 and decreasing the reaction temperatures for energy usage [1][2][3][4][5][6].…”

Catalytic performance of Ni/CaO-Ca 5 Al 6 O 14 bifunctional catalyst extrudate in sorption-enhanced steam methane reforming

“…This novel technology is normally called sorption-enhanced steam methane reforming (SESMR). Indeed, the concept of sorptionenhanced reaction process has recently also been applied to the steam reforming of ethanol and glycerol [11,12].…”