Zuzeng Qin

Superparamagnetic Supported Catalyst H3PW12O40/γ-Fe2O3 for Alkylation of Thiophene with Olefine

Abstract The alkylation of sulfur compounds with olefine is considered to be an attractive way to attain high level of sulfur removal by raising the boiling point of sulfur-containing compounds to ease their separation from light fractions by distillation. A series of superparamagnetic supported catalysts, used for alkylation of thiophene with 1-octene, were prepared by loading H 3 PW 12 O 40 (HPW) onto commercially available nanoparticles γ-Fe 2 O 3 through incipient wet impregnation method. The catalysts were characterized by X-ray diffraction (XRD), Fourier transform infra-red (FT-IR), thermo gravimetric analysis (TG), N 2 -adsorption and vibrating sample magnetometer (VSM). The physicochemical characterization reveals that γ-Fe 2 O 3 could be accommodated to immobilize and disperse HPW. Moreover, possessing high magnetization of 26.1 A·m 2 ·kg −1 and with mesoporous structure with specific surface area of 35.9 m 2 ·g −1 , the 40% (by mass) HPW loading catalyst is considered the proper catalyst for olefinic alkylation of thiophenic sulfur (OATS) and can be separated in an external magnetic field. The catalytic activity was investigated in the alkylation reaction of thiophene with 1-octene, and the conversion of thiophene is up to 46% at 160 °C in 3 h. The 40% (by mass) HPW/γ-Fe 2 O 3 catalyst can be reused 6 times without too much loss of activity and keeps its property of superparamagnetism.

Intrinsic Kinetics of Dimethyl Ether Synthesis from Plasma Activation of CO2 Hydrogenation over Cu-Fe-Ce/HZSM-5.

CO2 is activated in a plasma reactor followed by hydrogenation over a Cu-Fe-Ce/HZSM-5 catalyst, and the intrinsic kinetics of the plasma catalytic process are studied. Compared with CO2 hydrogenation using Cu-Fe-Ce/HZSM-5 alone, the CO2 conversion and the dimethyl ether selectivity for the plasma catalytic process are increased by 16.3u2009%, and 10.1u2009%, respectively, indicating that the CO2 was activated by the plasma to promote hydrogenation. A study of the intrinsic kinetics shows that the activation energies of methanol formation, the reverse water-gas shift reaction, and methanol dehydration to dimethyl ether are 149.34, 75.47, and 73.18u2005kJu2009mol-1 , respectively, which are lower than if Cu-Fe-Ce/HZSM-5 is used without plasma, indicating that the activation of CO2 in the plasma reduces the activation energy of the hydrogenation reaction and improves the yield of dimethyl ether.

Acid-treated bentonite-supported Ni catalysts via rapid microwave-assisted drying for nitrobenzene hydrogenation

ABSTRACT Acid-treated bentonite-supported Ni catalysts were prepared using a microwave-assisted drying process, characterized and used for the hydrogenation of nitrobenzene to aniline. Microwave-assisted drying of the catalyst reduced the drying time from 3u2009h with a traditional heating method to 10u2009min; after drying by microwave irradiation, the acid-treated bentonite-supported Ni catalysts were more stable due to a smaller crystallite size, a higher dispersion of metallic Ni and stronger interactions between Ni and the acid-treated bentonite support than the traditional drying method. Catalytic studies conducted at 300°C with a nitrobenzene liquid hourly space velocity of 3.6u2009mLu2009g−1u2009h−1 and a H2 gas hourly space velocity of 4,800u2009mLu2009g−1u2009h−1 indicated that the catalyst prepared using the microwave heating method maintained a nitrobenzene conversion of >99.9% with an aniline selectivity >93% during a 60-h reaction. In addition, the catalyst dried using a traditional method only functioned for 16u2009h.