Zhang Huiping

Synthesis of TiO2 nano-particles and their photocatalytic activity for formaldehyde and methyl orange degradation

TiO2 nano-particles were synthesized by sol-gel technique and characterized by X-ray diffractometer (XRD) and transmission electron microscope (TEM). Their photocatalytic activities for formaldehyde (FA) and methyl orange (MO) degradation were tested using degradation rate (η) as an evaluation index. Based on the orthogonal test results, the optimal condition for TiO2 preparation was obtained. Results showed that particle sizes were in the range of 10–40 nm, and that prepared TiO2 had better photocatalytic activity than P25. A simplified model was developed to evaluate the apparent quantum efficiency (Φapp) of this photocatalytic reaction system.

Total oxidation of isopropanol over manganese oxide modified ZSM-5 zeolite membrane catalysts

Manganese oxide modified ZSM-5 membrane catalysts were prepared for the catalytic combustion of a volatile organic compound (isopropanol) over a zeolite membrane reactor. Characterization of all samples was carried out by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), N2 adsorption/desorption, X-ray photoelectron spectroscopy (XPS) and H2-temperature programmed reduction (H2-TPR). The performance of the catalytic oxidation of a single VOC (isopropanol) was investigated over the zeolite membrane reactor based on Mn/ZSM-5/PSSF catalysts, the experimental results showed that the 0.5 M Mn/ZSM-5/PSSF-350 °C catalyst exhibited the best catalytic activity for isopropanol oxidation with 90% conversion of isopropanol at 222 °C with a feed concentration of 4.5 mg L−1 and GHSV of 7643 h−1, which was much lower than that of granular Mn/ZSM-5 catalyst (297 °C). The results of a reaction stability test revealed that the Mn/ZSM-5/PSSF catalysts possess excellent reaction stability for isopropanol oxidation for 50 h, and the conversion of isopropanol remained above 97% at 280 °C with a feed concentration of 4.5 mg L−1 and GHSV of 7643 h−1.