An experimental and kinetic modeling study of CO2 hydrogenation to CO over Cu-Al catalyst utilizing MFB-TGA-MS

Carbon capture, utilization, and storage (CCUS) are essential technologies for realizing carbon neutrality in the context of fossil fuel decarbonization. Integrated carbon capture and utilization, in conjunction with the reverse water gas shift reaction (ICCU-RWGS), presents a promising strategy for the in-situ conversion of CO2. This ap-proach mitigates the energy penalties associated with CO2 capture and eliminates the additional costs associated with storage and transportation. In this study, we employed a Cu-Al composite catalyst, prepared using the im-pregnation method, for ICCU-RWGS, with a specific focus on CO2 hydrogenation. The kinetics of hydrogenation for the Cu-Al catalyst were comprehensively investigated using micro-fluidized bed thermogravimetric analysis coupled with mass spectrometry (MFB-TGA-MS). The results indicate that, when subjected to experimental condi-tions involving 800 degrees C, 20 vol.% CO2, 30 vol.% H 2 , and a sample mass of 1 g, the comprehensive evaluation reveals a CO2 conversion rate of 43.67 %. This conversion is accompanied by 100 % CO selectivity and a reaction rate of 0.10 mmol center dot g- 1 center dot s- 1 , respectively. Furthermore, we calculated the kinetic parameters for the CO2 hydrogenation by analyzing the MFB-TGA-MS data, utilizing the simplified K-L model for fluidized beds. The results indicated an activation energy of 55.8 kJ center dot mol - 1. These findings highlight the effectiveness of ICCU-RWGS methodologies, especially concerning CO2 hydrogenation, and present a compelling case for their further commercialization.