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The deactivation of Pt/WOx/Al2O3 and Pt-Ru/WOx/Al2O3 catalysts in the glycerol hydrogenolysis to 1,3-propanediol (1,3-PDO) was investigated in autoclave. The selectivity of both catalysts toward 1,3-PDO was within 50–56% after the first five usages at 170 °C for 12 h with a H2 pressure of 9 MPa. With Pt/WOx/Al2O3, the conversion of glycerol decreased from 44.3% (1st reaction) to 27.2% (5th reaction), whereas a conversion of 52.4%, 48.0%, and 48.4% was obtained in the 1st, 5th, and 20th reactions, respectively, when Pt-Ru/WOx/Al2O3 was used. The characterizations of the catalysts showed that the pore structure of the catalyst changed because of the crystal structure of the catalyst support changing from γ-Al2O3 to pseudo-boehmite. However, the changes of the catalyst morphology were not responsible for the catalyst deactivation. Simultaneously, the acidity of catalysts was not shown to be a factor in their deactivation. On the other side, catalysts were not deactivated as a result of the loss of active components. Catalyst deactivation during glycerol hydrogenolysis was finally caused by the aggregation of active metal particles (Pt or Pt-Ru). [ABSTRACT FROM AUTHOR]

The dissolution process of metal oxide catalysts in the alcoholysis of urea by 1, 2‐propylene glycol (PG) to the synthesis of propylene carbonate (PC) was investigated. It was found that the reaction was mainly catalyzed by homogeneous catalysts. The metal oxide reacted with ammonia and isocyanate acid, the decomposition products of urea, to form a complex and dissolved into the reaction system. The dissolved amount of catalyst was positively correlated with the PC yield by using different oxides and salts as catalysts. The Fourier‐transform infrared spectroscopy (FTIR) result of the catalysts reacting with urea showed that the dissolution‐precipitation process of the catalysts was related to the decomposition of urea. The results of catalytic test indicated that both the dissolved amount of catalysts and the structure of the complex affected PC yields. A reaction mechanism was proposed based on the results. From the mechanism, a complex catalyst with at least two ammonia ligands is better for this reaction. [ABSTRACT FROM AUTHOR]

Amino‐functionalized halide ionic liquids, aminopropyl‐3‐butyl‐imidazolium ([Apbim]+) with different halogen anions, and their zinc halide mixing catalysts were prepared and used to catalyze the cycloaddition of CO2 to propylene oxide (PO) without solvent. Under ideal conditions, the conversion of PO could reach 93.5 % with the catalysis of [Apbim]Cl. Under optimized conditions of catalyst dosage, reaction temperature, CO2 pressure, and reaction time, with the catalysis of [Apbim]I, [Apbim]Cl/ZnBr2 (3:1), and [Apbim]Br/ZnBr2 (5:1), the conversion of PO and the selectivity of propylene carbonate (PC) both reach > 99 %. From the point of view of preparation process and industrial operation, [Apbim]Cl/ZnBr2 is the most suitable catalyst. This catalyst is characterized by good reusability and catalytic activity, and the yield of PC is about 99 % at least for ten times repeated use. [ABSTRACT FROM AUTHOR]

Alcoholysis of urea with 1,2‐propylene glycol (PG) is a potential industrial process for the synthesis of propylene carbonate (PC) with many advantages. However, the preparation of industrial catalysts such as Zn‐Al oxide by the co‐precipitation method will inevitably produce a large amount of salty water and building desalting equipment will increase the investment cost. The present work attempts to use a mechanically mixed catalyst consisting of commercial ZnO and Al2O3 to solve these problems. This type of catalyst was capable of catalyzing the reaction more than 5 times. The PC yield was gradually increased with each use. The best PC yield of 96.7% is comparable to the co‐precipitated Zn‐Al oxide catalysts and was achieved during the third use. In the reaction, ZnO and Al2O3 were dissolved into the reactants to form complexes, which homogenously catalyzed the reaction. It was found that the dissolved Zn and Al complex significantly influenced the PC yield and re‐precipitated in the late stage of the reaction. Furthermore, the partial dissolution of Al assisted the dissolution and precipitation of Zn, which improved the PC yield. After several dissolution‐precipitation cycles, ZnO‐Al2O3 was homogeneously mixed at the atomic scale. Interestingly, there was an adequate linear relationship between the amount of dissolved Zn and Al in each reaction, the linear correlation coefficient improved after each reaction, and the slope of the line (the ratio of dissolved Zn/Al) was 7.26 in the third use. [ABSTRACT FROM AUTHOR]

A novel core-shell catalyst as [(Ni/MgAl2O4)@SiO2] was successfully prepared by three steps. First, the support was prepared, then 10 wt% Ni was loaded upon the support by the wetness incepting impregnation method; finally, the catalyst was coated with mesoporous silica. Two supports with different sizes were synthesized by homogeneous precipitation method and solution combustion method, respectively. Based on different supports, two series of catalysts with the characteristics of same components and different particle diameters were obtained. All catalysts were characterized by X-ray diffraction, transmission electron microscopy, N2-physisorption and thermal gravimetric analyzer to measure the crystallinity, morphology, surface structure and carbon deposition. The results shown that core-shell catalysts [(Ni/MgAl2O4)@SiO2] had better coke-resistance and stability than the uncoated catalysts (Ni/MgAl2O4). Therefore, core-shell catalyst coated by silica exhibited better performance in dry reforming of methane. [ABSTRACT FROM AUTHOR]

Objective This paper explores the relationships between mental health status of the patients' parents, whose children have cleft lip and palate, and their social impact factors. Methods The 12-item general health questionnaire (GHQ-12) and the social support rating scale were used to conduct a questionnaire survey of 59 patients' parents. A data statistical analysis was done by using SPSS 13.0 software and Excel 2007 software. Results 1)The mental health status of the patients' parents was in the middle level. 2) The mental health status of the patients' parents was related with the basic personal Situations. It was apparently influenced by the qualifications and subjective state of mind. 3) The structure and relationship of the interpersonal networks of the patients' parents were the major constraint factors on the mental health status. 4) The social support degree and mental health status were positively correlated. Conclusion The social network and social support have important influences on the mental health status of the parents whose children have cleft lip and palate. It should create a more harmonious and tolerant social environment. [ABSTRACT FROM AUTHOR]

Objective: This paper explores the relationships between mental health status of the patients' parents, whose children have cleft lip and palate, and their social impact factors., Methods: The 12-item general health questionnaire (GHQ-12) and the social support rating scale were used to conduct a questionnaire survey of 59 patients' parents. A data statistical analysis was done by using SPSS 13.0 software and Excel 2007 software., Results: 1)The mental health status of the patients' parents was in the middle level. 2) The mental health status of the patients' parents was related with the basic personal situations. It was apparently influenced by the qualifications and subjective state of mind. 3) The structure and relationship of the interpersonal networks of the patients' parents were the major constraint factors on the mental health status. 4) The social support degree and mental health status were positively correlated., Conclusion: The social network and social support have important influences on the mental health status of the parents whose children have cleft lip and palate. It should create a more harmonious and tolerant social environment.