Photocatalytic conversion of carbon dioxide and methane over titania nanoparticles coated mesh: Optimization study

Immobilized titania (TiO₂) nanoparticles semiconductor on stainless steel mesh was used for photocatalytic conversion of CO2 and CH4. This study utilized experimental design and process optimization tools t o maximize the desired response using response surface methodology (RSM) with central composite rotatable design (CCRD). The experimental parameters were stainless steel mesh size, titania nanoparticles loading, calcination temperature, UV light power and initial ratios of CO2:CH4:N2 in feed. The optimal conditions were determined as follows: stainless steel mesh size of 140, 4 g of coated titania nanoparticles on mesh, calcination temperature of 600 oC, UV light power of 250 W and 10% of CO2 in feed to achieve a maximum CO2 conversion of 37.87%. Correspondingly, the selectivity of products were 4.66%, 4.28%, 3.97% and 87.09%, for ethane, acetic acid, formic acid and methyl acetate, respectively.