Integrated syngas and nitrogen production in La0.6Ca0.4Co0.2Fe0.8O3−δ hollow fiber membrane reactor through oxidative CO2 reforming of methane

Abstract

Utilizing mixed ion-electronic conducting (MIEC) oxygen permeable ceramic membrane to introduce oxygen from air into the oxidative CO2 reforming of methane (OCRM), which integrates exothermic partial oxidation of methane (POM) with endothermic dry reforming of methane (DRM), not only reduces the energy consumption but also effectively mitigates carbon accumulation. In this study, La0.6Ca0.4Co0.2Fe0.8O3−δ (LCCF) hollow fiber (HF) membrane was fabricated via a phase inversion and sintering technique using LCCF oxide powder. A 10 wt% Ni/LCCF catalyst was prepared by mechanical mixing and high temperature reduction of NiO and LCCF powder. The catalyst and LCCF HF membrane were integrated into an OCRM membrane reactor. The findings indicate that moderate temperature increment was beneficial to the combined OCRM reaction in the membrane reactor. However, the increase in air flow rates, CH4/CO2 ratio, and feed flow rates were found to deteriorate the OCRM performance. At 825 °C, the CO selectivity and carbon balance were maintained at about 99 %. The stabilized oxygen permeation rate at about 2.08 mL min−1 signifies that the permeated oxygen significantly inhibits carbon accumulation in the catalyst. Notably, N2 with purity of 99.47 vol% was obtained at the air feed side of the setup, underlining the potential for efficient carbon management and high-purity N2 production within this OCRM membrane reactor.