Preparation and application of Co3O4 catalysts from ZIF-67 membranes over paper-like stainless steel fibers in isopropanol combustion

Abstract

Co3O4 catalysts supported on paper-like stainless steel fibers (PSSF) were prepared by MOFs-templated (M) method and applied for catalytic combustion of isopropanol. Physicochemical properties of the as-synthesized Co3O4 catalysts were investigated by SEM, EDS mapping, TEM, XRD, BET, XPS and H2-TPR, respectively. Characterization results of SEM and TEM shown that Co3O4 (M)-350 and Co3O4 (M)-400 still remained the dodecahedron shape of the ZIF-67 precursor and possessed porous structures. The XPS results shown that the ratio of Co3+/Co2+ and Oc/Oc ​+ ​Oa ​+ ​Ol firstly increased and then decreased with the increase of calcination temperature. Among the as-synthesized catalysts, Co3O4(M)-400 exhibited the highest activity for the catalytic combustion of isopropanol with the T50 and T90 values of 258 ​°C and 281 ​°C, respectively, which was associated with high BET surface area, high amount of Co3+ species and abundant surface chemisorbed oxygen. Moreover, Co3O4 (M)-400 was employed as a structured catalyst for isopropanol combustion, the catalytic kinetics were studied based on different feed concentration, bed height and GHSV. The experimental results indicated that the T50 and T90 of isopropanol combustion over Co3O4(M)-400 with the bed height of 2 ​cm were increased slightly as the GHSV and feed concentration of isopropanol increased.