Oxidative coupling of bio-alcohols mixture over hierarchically porous perovskite catalysts for sustainable acrolein production

RSC Adv. 2021 Aug 31;11(46):28961-28972. doi: 10.1039/d1ra05627a. eCollection 2021 Aug 23.

Abstract

The acrolein production from bio-alcohols methanol and ethanol mixtures using AMnO3 (since A = Ba and/or Sr) perovskite catalysts was studied. All the prepared samples were characterized by XRD, XPS, N2 sorption, FTIR, Raman spectroscopy, TEM, SEM, TGA, and NH3-CO2-TPD. The catalytic oxidation reaction to produce acrolein has occurred via two steps, the alcohols are firstly oxidized to corresponding aldehydes, and then the aldol is coupled with the produced aldehydes. The prepared perovskite samples were modified by doping A (Sr) position with (Ba) to improve the aldol condensation. The most catalytic performance was achieved using the BaSrMnO3 sample in which the acrolein selectivity reached 62% (T = 300 °C, MetOH/EtOH = 1, LHSV = 10 h-1). The increase in acrolein production may be related to the high tendency of BaSrMnO3 toward C-C coupling formation. The C-C tendency attributes to that modification have occurred in acid/base sites because of metal substitution.