Photocatalytic CO2 Reduction with H2O Vapours Using Montmorillonite/TiO2 Supported Microchannel Monolith Photoreactor.

Abstract:

In this study, the performance of a montmorillonite (MMT)/TiO₂ coated monolith photoreactor was tested for the photocatalytic CO₂ reduction. CH₄ and CO were the main products having yield rates of 139 and 52 μmole g catal.⁻¹ h⁻¹, respectively. The other adequately significant products were C₂H₄, C₂H₆, C₃H₆ and C₃H₈. The catalytic reactor performance for CH₄ production was in the order of MMT–TiO₂–monolith (139 μmole g catal.⁻¹ h⁻¹) > TiO₂–monolith (82 μmole g catal.⁻¹ h⁻¹) > MMT–TiO₂–cell (43 μmole g catal.⁻¹ h⁻¹) > TiO₂–cell (7.7 μmole g catal.⁻¹ h⁻¹). The higher yield rates in monolith photoreactor were due to the higher illuminated surface area and efficient light utilization. In addition, the profound hydrocarbon yield rates over MMT/TiO₂ nanocatalyst supported microchannels were due to the efficient production and utilization of charges. The reaction rate and the adsorption–desorption phenomenon was postulated according to the Langmuir–Hinshelwood (L–H) model. A simple kinetic equation, derived to model the coupled effect of adsorptive photocatalytic reduction and oxidation, fitted-well with the experimental data.

1. Muhammad Tahir and Nor Aishah Saidina Amin (2013). Photocatalytic CO2 reduction with H2O vapors using montmorillonite_TiO2 supported microchannel monolith photoreactor. Chemical Engineering Journal, 230, 314-327, Elsevier. (2012 I.F = 3.461)