Co-Ru catalysts with different composite oxide supports for Fischer–Tropsch studies in 3D-printed stainless steel microreactors

Abstract

Bimetallic Co-Ru on different mesoporous composite oxides (m-SiO2-Al2O3, m-SiO2-TiO2, m-TiO2-Al2O3) and CoRu-m-SiO2-TiO2 were synthesized by incipient wet-impregnation (IWI) and one-pot (OP) hydrothermal methods, respectively. Bimetallic catalysts were coated in the microchannels of 3D-printed stainless steel (SS) microreactors for Fischer-Tropsch (FT) studies. The physiochemical properties of the catalysts were examined by BET, XRD, SEM, TEM, TPR, TGA-DSC and XPS techniques. The TPR results showed that the method and the composite support had a profound effect on the reducibility of the active sites. All the catalysts resisted deactivation for first 50 h and 10Co5Ru/m-SiO2-TiO2 (IWI) was most stable with ∼80 % CO conversion at the end of 60 h. The stability and activity of the catalysts were observed in the order: 10Co5Ru/m-SiO2-TiO2 (IWI) >10Co5Ru/m-SiO2-Al2O3 (IWI) >10Co5Ru/m-Al2O3-TiO2 (IWI) >10Co5Ru-m-SiO2-TiO2 (OP). The TPO and XRD analyses of the spent catalysts confirmed coking as a potential factor but not the only cause of catalyst deactivation over time.