Intensified bio-oil steam reforming for high-purity hydrogen production: Numerical simulation and sorption kinetics

Abstract

This work proposes the production of high-purity hydrogen by an intensified non-isothermal sorption-enhanced bio-oil steam reforming (SEBOSR) process, by combining the bio-oil steam reforming over a Ni/La2O3-αAl2O3 catalyst and in-situ CO2 adsorption over Li2CuO2. The kinetics of CO2 adsorption on Li2CuO2 was studied experimentally and applied to assess the performance of SEBOSR in a fixed bed reactor via a non-isothermal mathematical model. Model simulations show that the prebreakthrough stage of the SEBOSR process, which corresponds to high purity H2 production, can be extended by increasing the adsorbent loading and the S/C ratio, as well as by decreasing the inlet gas velocity. Increasing inlet temperature generates longer prebreakthrough step times but leads to a reduction in hydrogen purity. This intensified process allows to diminish the catalyst deactivation, which ultimately only occurs in the inlet region of the packed bed to some extent. In addition, SEBOSR indirectly uses sustainable CO2-neutral biomass as a source of hydrogen; highly pure and renewable H2 can be produced in one step (without the need of additional gas purification), via a process with enhanced thermal efficiency.