Co–Mo–O bimetallic oxides were prepared as efficient catalysts for aerobic oxidative desulfurization with oxygen in air as the oxidant.

The present research relates a universally practical and feasible approach toward chemically deconstructing the macromolecular architecture of lignin, specifically alkali lignin (AL), for the production of a number of valuable side-stream aromatic nuclei byproducts. The hydrothermolysates obtained at different subcritical conditions were tentatively qualitatively identified by gas chromatography mass spectrometry (GC-MS) and subsequently quantified by gas chromatography (GC). The influence of temperature (220−340 °C), residence time (0−60 min), and ethanol volume-% in a water−ethanol cosolvent (0− 100%) on the conversion of AL and the yield of the side-stream (liquid) products were explored. The results show that the yield and identity of the phenolic and methoxy-benzene compounds were strongly correlated to the conversion temperature and the ethanol volume-%, whereas residence time in the autoclave had only a minor influence. The following individual chemicals (mg liquid side-stream/g lignin) and associated yields were determined from the optimal hydrothermal conditions (30 min, 310 °C, 25% ethanol): phenol (4.25 mg/g), 4-methylguaiacol (2.93 mg/g), 3,5-dimethoxyacetophenone (0.78 mg/g), 1,2,4trimethoxybenzene (2.47 mg/g), and 2,6-dihydroxy-4-methoxyacetophenone (2.47 mg/g). The highest yield of guaiacol (11.87 mg/g) and 2,6-dimethoxyphenol (12.17 mg/g) was obtained at a reaction temperature of 310 °C over 60 min in neat water.

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The investigation of wet air oxidation of cerium(III) (Ce(III)) of rare earth (RE) hydroxides was carried out in this work. The effects of air flow rate, reaction temperature, reaction time, solution pH, and anions of F − and PO 4 3− on the oxidation rate were investigated. Under the conditions of air flow rate of 3 L min −1 , reaction temperature of 80°C, reaction time of 4 h, and pH 13, the oxidation rate of Ce(III) could reach nearly 97%. According to the kinetics study of oxidation, the reaction order for wet air oxidation was found to be 1 with respect to the concentration of Ce(III) in the suspension at a temperature range of 40−80°C, and the apparent activation energy was calculated to be 10.49 kJ mol −1 . The investigation of oxidation processes in practical systems indicated that RE-hydroxides, which contained fluorine and phosphor and were derived from the treatment of Bayan Obo mixed RE concentrate, could be successfully oxidized by air.