Synthesis and eva‎luation of Fe-Cr Free Based Catalysts for High Temperature Water Gas-Shift Reaction

5/16/2023 12:00:00 AM

The steady growth of the population has doubled the growing need for energy used in industry. The use of hydrocarbon fuels to date has led to adverse climatic and environmental changes, and debates over their non-renewability have led various governments to try to find alternative and renewable fuels. Has pushed. In the meantime, H2 is mentioned as a suitable choice to replace hydrocarbon fuels. One way to produce hydrogen is to use catalyst-based methods. The water-gas shift reaction (WGSR) is used to produce hydrogen in ammonia synthesis units. This process is performed in two stages: low temperature water-gas shift reaction (LT-WGSR) in the range (180-280°C) and high temperature water-gas shift reaction (HT-WGSR) in the range (310 – 450°C) is done. Conventional catalysts used in HT-WGSR are Fe-Cr catalysts, which have harmful environmental effects due to their carcinogenicity of hexavalent chromium (Cr6+). Hence the discussion of replacing chromium with other metals. In the present study, various catalytic bases based on iron oxide were synthesized and analyzed. All catalyst bases were prepared by mechano-chemical synthesis method, which produces less solvent waste than other synthesis methods. Among the synthesized catalysts, Fe-Ce catalysts showed better thermal stability compared to Fe, Fe-Cr and Fe-Al samples. In order to increase the activity, the active metal nickel (Ni) was used in different weight ratios, which in addition to increasing the catalyst activity, also caused a side effect of methanation. Among the different values, the sample containing 10% by weight of nickel showed the best activity. NiO and K2O compounds were used as promoters to suppress the methane formation resulting from the reaction. Eventually, the potassium containing catalyst surprisingly suppressed methane formation.

خالص‌سازي هيدروژن , واكنش انتقال آب-گاز دما بالا , كاتاليست‌ مبتني بر آهن عاري از كروم , سركوب متان سازي , تبديل درصد CO

Hydrogen Purification , High Temperature Water-Gas Shift Reaction , Fe-Cr Free Based Catalyst , Methanation Suppression , CO Conversion

Meisam Nezhad Hassan

Dr. Mehran Rezaei