Optimizing the Performance of the Meso-Scale Continuous-Flow Photoreactor for Efficient Photocatalytic CO2 Reduction with Water Over Pt/TiO2/RGO Composites

Abstract

AbstractTuning the reaction parameters to maximize products yield is one of the major needs for any process. The goal of this research is to increase the reduction of CO2 with water by examining the operating parameters of a meso-scale continuous-flow type photochemical reactor over hydrothermally synthesized photocatalysts such as Pt/TiO2 and Pt/TiO2/RGO. Effects of catalyst type, weight of catalyst utilized, photochemical reactor temperature, retention time by variating the liquid water flow rate, and cocatalyst loading were investigated to increase the concentration of total organic carbon compounds including HCHO and CH3OH. The effect of titanium dioxide phase ratio (anatase: rutile) presence at the Pt/TiO2/RGO photocatalysts was also studied. The results revealed that the 0.3 wt.% Pt/TiO2/RGO5% photocatalyst which includes a phase ratio of 81:19 for anatase: rutile respectively has the superior photocatalytic activity to other studied photocatalysts. The physciochemical properties of different prepared photocatalytic samples were determined using various characterization techniques. Analyzing the liquid products on gas chromatography, it was found that CH3OH represents the major product whereas HCHO was the minor one. This reactor exhibits a great performance towards CO2 photocatalytic reduction under the optimized conditions. Graphical Abstract