On the solution combustion synthesis of copper based nanocatalysts for steam methanol reforming: Effect of precursor, ultrasound irradiation and urea/nitrate ratio

Abstract

Steam reforming of methanol over CuO/ZnO/Al2O3 nanocatalysts synthesized by ultrasound assisted urea-nitrates combustion method was investigated. Four kinds of nanocatalysts were fabricated and their characteristic properties were studied by XRD, FESEM, PSD, BET, EDX and FTIR analyses. Their physicochemical properties proved that using boehmite instead of aluminium nitrate as the aluminium precursor leads to smaller crystallites and particles, better dispersion and more surface area and subsequently higher activity in the steam methanol reforming process. Furthermore, application of sonication for mixing of the primary gel of combustion method resulted in better dispersion of active phases, smaller and more homogeneous particles, higher methanol conversion and hydrogen production. Although enhancement of fuel/nitrates ratio increased dramatically the surface area of synthesized nanocatalysts but it had no significant effect for improving methanol conversion or hydrogen production. In a word, CZA-A-CU-UN1 had better physicochemical properties and catalytic performance for the steam methanol reforming process.