Reverse water gas shift reaction over tungsten carbide prepared catalyst from waste date palm fronds at low temperatures reverse water gas shift reaction

Abstract

The reverse water gas shift reaction over the prepared tungsten carbide alloy (WC/AC) from date palm fronds catalyst was studied by CO₂ hydrogenation, temperature-programmed reduction of the WC/AC catalyst. In comparison to the reaction of CO₂ alone, hydrogen can significantly promote the CO formation in the RWGS reaction. The formate derived from association of H₂ and CO₂ is proposed to be the key intermediate for CO production. Formate dissociation mechanism is the major reaction route for CO production. The reverse water gas shift (RWGS) reaction over WC/AC with potassium (K) promoter was studied by means of CO₂ hydrogenation at temperature programmed. The main role of Potassium oxide (K₂O) was to provide catalytic activity for decomposition of formats, besides acting as a promoter for CO₂ adsorption. Hydrogen was dissociatively adsorbed on WC/AC and could spill over to K₂O to associate with CO₂. This resulted in the formation of formate species for the production of CO.