Preparation of soybean oil factory sludge catalyst and its application in selective catalytic oxidation denitration process

Abstract SCO (selective catalytic oxidation) was a new denitration process, and it was used in low temperature environment and in this study. The soybean oil factory sludge (named SOFS) was a solid waste, but preparing it as a denitration catalyst can reduce environmental pollution. SOFS was activated by using equal volume of solution, and it was activated by strong acids (HCl, HNO 3 , HClO 4 ), strong alkalis (LiOH, NaOH, KOH), different concentrations (5%, 10%, 15%, 20%) and different activation time (2 h, 3 h, 4 h, 5 h). And then muffle furnace roasting and plasma roasting methods were selected to prepare MnO/SOFS catalyst with incipient impregnation. The catalyst was characterized by Fourier Transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and scanning electron microscope (SEM). The experimental results showed that: (1) The optimum activation conditions for denitration catalyst were obtained, LiOH had the best activation effect, its concentration was 15%, and its activation time was 4 h; compared with the original SOFS, the denitration rate increased from 78% to 90%. (2) MnO/SOFS catalyst roasted by the plasma had the best denitration effect, its denitration rate reached 98%, and the conditions of the plasma were O 2 flow rate of 800 ml/min, calcination power of 60 W and calcination time of 30 min.