Effect of Calcination Time on Catalyst’s Activity and Stability

Abstract

Based on the catalyst Pd-Fe-Co-Ce/FSC(ratio 1:1:1:3), a catalytic wet oxidation method was used to treat organic waste-water that is difficult to biodegrade. The calcination temperature of the catalyst was set to 550 °C, and the calcination time was set to 1 h, 3 h, 5 h, 7 h in order. From the analysis, it is found that the effluent pH first decreases and then increases. With the extension of the reaction time, the absorbance of the treated waste-water decreases, and the decolorization rate increases. With the extension of the reaction time, the COD of the treated water sample decreased and the COD removal rate increased. For catalysts No.1, No.2, No.3 and No.4, the COD of wastewater was 10851, 768, 1149 and 1238 mg/L at 120 min of catalytic wet oxidation of wastewater, and the corresponding COD removal rates was 84.1%, 88.7%, 83.1% and 81.8%, respectively. The experimental results showed that the catalyst prepared by calcining for 3 h had a COD removal rate and a decolorization rate of 88.7% and 97.9%, respectively, and the metal dissolution solubility of the treated water was relatively low. 3 h is a suitable catalyst’s calcination time.