We investigated the effects of supports （CMK-3, SiO2ZrO2, MgO, Al2O3） and promoters （Cu, Ce, Fe） on textual properties of Ni based catalysts. o-Cresol was used as a probe to test the activity of these catalysts un...We investigated the effects of supports （CMK-3, SiO2ZrO2, MgO, Al2O3） and promoters （Cu, Ce, Fe） on textual properties of Ni based catalysts. o-Cresol was used as a probe to test the activity of these catalysts under the condition of 230 ℃ and nitrogen pres-sure of 0.1 MPa. The catalysts were characterized by X-ray diffraction, H2 temperature programmed reduction ammonium programmed desorption, and N2 adsorption-desorption isotherms. The results showed that the catalytic performance of Ni/CMK-3 （the conversion of o-cresol reached 45.4%） was significantly better than the other three kinds of supports. The modification of Ni/CMK-3 was also investigated and over 60% conversion of o-cresol was obtained after the addition of Ce （64.6%）and Cu （66.8%） in Ni/CMK-3, whereas the addition of Fe led to a decrease of conversion. In the meantime, Cu changed the products dis-tribution. The appearance of toluene indicated that another pathway existed in the reaction.Accompanied by the ascension of conversion in both sides, side effects also occurred and got more serious. The apparent order of activity for all the tested catalysts was NiCe/CMK-3〉NiCu/CMK-3〉Ni/CMK-3〉NiFe/CMK-3〉Ni/Al2O3Ni/SiO2ZrO2〉Ni/MgO. The reac-tion pathway, involving three routes, was also mentioned in this study.展开更多
The supercritical water gasification of phenolic wastewater without oxidant was performed to degrade pollutants and produce hydrogen-enriched gases. The simulated o-cresol wastewater was gasified at 440-650℃ and 27.6...The supercritical water gasification of phenolic wastewater without oxidant was performed to degrade pollutants and produce hydrogen-enriched gases. The simulated o-cresol wastewater was gasified at 440-650℃ and 27.6 MPa in a continuous Inconel 625 reactor with the residence time of 0.42-1.25 min. The influence of the reaction temperature, residence time, pressure, catalyst, oxidant and the pollutant concentration on the gasification efficiency was investigated. Higher temperature and longer residence time enhanced the o-cresol gasification. The TOC removal rate and hydrogen gasification rate were 90.6% and 194.6%, respectively, at the temperature of 650℃ and the residence time of 0.83 min. The product gas was mainly composed of H2, CO2, CFL and CO, among which the total molar percentage of H2 and CFL was higher than 50%. The gasification efficiency decreased with the pollutant concentration increasing. Both the catalyst and oxidant could accelerate the hydrocarbon gasification at a lower reaction temperature, in which the catalyst promoted H2 production and the oxidant enhanced CO2 generation. The intermediates of liquid effluents were analyzed and phenol was found to be the main composition. The results indicate that the supercritical gasification is a promising way for the treatment of hazardous organic wastewater.展开更多
The two novel green oxidation processes of p/o-cresols to p/o-hydroxybenzaldehydes catalyzed by metalloporphyrins in the presence of molecular oxygen were developed in this work.Among the metalloporphyrins with differ...The two novel green oxidation processes of p/o-cresols to p/o-hydroxybenzaldehydes catalyzed by metalloporphyrins in the presence of molecular oxygen were developed in this work.Among the metalloporphyrins with different central ions and substituents studied,T(p-NO 2)PPCoCl and T(p-OCH 3)PPFeCl presented the highest activities for p-cresol and o-cresol oxidation reactions respectively.The molar ratio of sodium hydroxide to cresols and different reaction parameters including reaction temperature,reaction time and reaction pressure have been investigated,and 69.8%/50.4% conversions of p/o-cresol and 86.6%/26.6% selectivities for p/o-hydroxybenzaldehydes were reached under optimized conditions.展开更多
基金This work was supported by the National Natural Science Foundation of China （No.51036006 and No.51106108） and the Key Program of the Chinese Academy of Sciences （No.KGZD-EW-304-3）.
文摘We investigated the effects of supports （CMK-3, SiO2ZrO2, MgO, Al2O3） and promoters （Cu, Ce, Fe） on textual properties of Ni based catalysts. o-Cresol was used as a probe to test the activity of these catalysts under the condition of 230 ℃ and nitrogen pres-sure of 0.1 MPa. The catalysts were characterized by X-ray diffraction, H2 temperature programmed reduction ammonium programmed desorption, and N2 adsorption-desorption isotherms. The results showed that the catalytic performance of Ni/CMK-3 （the conversion of o-cresol reached 45.4%） was significantly better than the other three kinds of supports. The modification of Ni/CMK-3 was also investigated and over 60% conversion of o-cresol was obtained after the addition of Ce （64.6%）and Cu （66.8%） in Ni/CMK-3, whereas the addition of Fe led to a decrease of conversion. In the meantime, Cu changed the products dis-tribution. The appearance of toluene indicated that another pathway existed in the reaction.Accompanied by the ascension of conversion in both sides, side effects also occurred and got more serious. The apparent order of activity for all the tested catalysts was NiCe/CMK-3〉NiCu/CMK-3〉Ni/CMK-3〉NiFe/CMK-3〉Ni/Al2O3Ni/SiO2ZrO2〉Ni/MgO. The reac-tion pathway, involving three routes, was also mentioned in this study.
文摘The supercritical water gasification of phenolic wastewater without oxidant was performed to degrade pollutants and produce hydrogen-enriched gases. The simulated o-cresol wastewater was gasified at 440-650℃ and 27.6 MPa in a continuous Inconel 625 reactor with the residence time of 0.42-1.25 min. The influence of the reaction temperature, residence time, pressure, catalyst, oxidant and the pollutant concentration on the gasification efficiency was investigated. Higher temperature and longer residence time enhanced the o-cresol gasification. The TOC removal rate and hydrogen gasification rate were 90.6% and 194.6%, respectively, at the temperature of 650℃ and the residence time of 0.83 min. The product gas was mainly composed of H2, CO2, CFL and CO, among which the total molar percentage of H2 and CFL was higher than 50%. The gasification efficiency decreased with the pollutant concentration increasing. Both the catalyst and oxidant could accelerate the hydrocarbon gasification at a lower reaction temperature, in which the catalyst promoted H2 production and the oxidant enhanced CO2 generation. The intermediates of liquid effluents were analyzed and phenol was found to be the main composition. The results indicate that the supercritical gasification is a promising way for the treatment of hazardous organic wastewater.
基金Supported by the Key Project of National Natural Science Foundation of China (21036009, 20776003)the Key Project of Natural Science Foundation of Beijing (2061001)the Funding Project for Academic Human Resources Development in Institutions of Higher Learning under the Jurisdiction of the Beijing Municipality (PHR 200907105, PHR 201107104)
文摘The two novel green oxidation processes of p/o-cresols to p/o-hydroxybenzaldehydes catalyzed by metalloporphyrins in the presence of molecular oxygen were developed in this work.Among the metalloporphyrins with different central ions and substituents studied,T(p-NO 2)PPCoCl and T(p-OCH 3)PPFeCl presented the highest activities for p-cresol and o-cresol oxidation reactions respectively.The molar ratio of sodium hydroxide to cresols and different reaction parameters including reaction temperature,reaction time and reaction pressure have been investigated,and 69.8%/50.4% conversions of p/o-cresol and 86.6%/26.6% selectivities for p/o-hydroxybenzaldehydes were reached under optimized conditions.
