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Abstract In this study, hierarchically porous perovskite catalysts of a general formula ABO3 concerning with three sample’s categories; Intrinsic perovskites (BaMnO3 (BMO) and SrMnO3 (SMO)), their A-site substituted perovskites; modified by substitution of the A-site (Ba+2) with a cation of the same oxidation state as Sr+2 (Ba0.5Sr0.5MnO3 (BSMO) and Ba0.5Sr0.5FeO3 (BSFO)) and their B-site substituted ones; modified by substitution of B-site (Mn+4) using cation with different oxidation state like Fe+3 (BaMn0.5Fe0.5O3 (BMFO) and SrMn0.5Fe0.5O3 (SMFO)), were prepared using hydrothermal method. Their characteristic properties were investigated by XRD, FTIR, Raman spectroscopy, XPS, N2 sorption, TEM, NH3- CO2-TPD, SEM and EDX. The prepared perovskite samples were modified in order to improve acid/base character and to enhance their effectiveness as catalysts especially in oxidation reactions. The role of A and B-site substitutions have been tested for oxidative coupling of primary alcohols (a methanol/ ethanol mixture of molar ratio ” " ~ " ” 1) into value-added products. The data indicate that, acrolein, acetaldehyde and formaldehyde were found to be the main products under different reaction condition (temperature and flow rate) using different perovskite catalysts. The highest catalytic performance was achieved using the BaSrMnO3 perovskite catalyst, in which the acrolein selectivity reached 62% (T=300 °C, MetOH/EtOH=1, LHSV=10 h−1), followed by SrMnFeO3, BaSrFeO3, BaMnFeO3, SrMnO3 then BaMnO3, respectively. Introduction of basic elements led to an increase in the number of acid/base pairs then to an improvement of the target molecule yields, which elucidates high acrolein selectivity. The high activity was attributed to the significant high rate of C- C bond formation over BaSrMnO3 relative to others. These catalysts propose promising yields of acrolein which make it a superb choice to be effective in a viable process. |