The one-pot synthesis of 6-hydroxyhexanoic acid from cyclohexanone via the integrated Baeyer-Villiger oxida-tion and ring opening reaction catalyzed by dealuminated HBEA zeolite has been developed. Under optimized con...The one-pot synthesis of 6-hydroxyhexanoic acid from cyclohexanone via the integrated Baeyer-Villiger oxida-tion and ring opening reaction catalyzed by dealuminated HBEA zeolite has been developed. Under optimized conditions,the cyclohexanone conversion and 6-hydroxyhexanoic acid selectivity are over 95%, respectively. The excellent catalyticperformance is attributed to the activation of carbonyl group of cyclohexanone and the fast hydrolysis and ring opening ofs-caprolactone by both Lewis acid and Br0nsted acid sites under aqueous conditions.展开更多
The inactivation of bacterial cells through catalyzed oxidation using hydrogen peroxide as the primary oxidant agent is dependent on a series of factors, such as the concentration of the catalyst, the rate of hydroxyl...The inactivation of bacterial cells through catalyzed oxidation using hydrogen peroxide as the primary oxidant agent is dependent on a series of factors, such as the concentration of the catalyst, the rate of hydroxyl radical formation in the controlled decomposition of the oxidant agent, and the concentration and toxicity of hydrogen peroxide. The objective of this study was to develop a mathematical model able to predict the kinetics of the inactivation Escherichia coli and total coliforms cells present in treated domestic sewage through catalytic peroxidation. The catalyst used was iron oxide supported on mineral coal (called CP), and the effects of the operational conditions, including hydrogen peroxide concentration and dosage of catalyst, were evaluated. The results showed that the disinfection kinetics of the treated domestic sewage is dependent on the concentrations of hydrogen peroxide and catalyst dosage. The kinetic model was shown to be able to predict the behavior of the inactivation kinetics of the bacterium Escherichia coli ATCC-25922 when different concentrations of hydrogen peroxide (75 and 100 mg·L^-1) were used, regardless of the catalyst dosage.展开更多
The use of nanostructured composites as catalyst supports is a promising route to prepare catalysts with high selectivity and productivity. In this work, reduced graphene oxide-TiO_2(rGP-x) composites with a variation...The use of nanostructured composites as catalyst supports is a promising route to prepare catalysts with high selectivity and productivity. In this work, reduced graphene oxide-TiO_2(rGP-x) composites with a variation of reduced graphene oxide(rGO) content were synthesized by hydrothermal method. Pd/rGP-x catalysts were prepared in incipient-wetness impregnation method for the direct synthesis of H_2O_2 from H2 and O_2. The morphology and electronic properties of catalysts were investigated by XPS, TEM, and Raman spectroscopy.The ratio of Pd^(2+)/Pd^0 and the hydrophobicity of the catalysts were increased with the rising content of rGO. As the amount of rGO in the catalysts varied in the range of 0.025 wt%–2 wt%, the selectivity of H_2O_2 exhibited a tendency of increasing firstly and then decreasing from 0.1 wt% to 2 wt%. It indicates that good catalytic performance for H_2O_2 synthesis can be achieved only when appropriate amount of rGO is introduced. The H_2O_2 selectivity and productivity of Pd/r GP-0.025 both improved remarkably compared with Pd/P25. This enhancement originated from the combined effects of the proper ratio of Pd^(2+)/Pd^0 and hydrophobicity of the catalyst.展开更多
基金supported by the National Basic Research Program of China(973 Program,2006CB202508)the China Petrochemical Corporation Program(SINOPEC Group ST417004)the National Key Research and Development Program of China(2017YFB0306800)
文摘The one-pot synthesis of 6-hydroxyhexanoic acid from cyclohexanone via the integrated Baeyer-Villiger oxida-tion and ring opening reaction catalyzed by dealuminated HBEA zeolite has been developed. Under optimized conditions,the cyclohexanone conversion and 6-hydroxyhexanoic acid selectivity are over 95%, respectively. The excellent catalyticperformance is attributed to the activation of carbonyl group of cyclohexanone and the fast hydrolysis and ring opening ofs-caprolactone by both Lewis acid and Br0nsted acid sites under aqueous conditions.
文摘The inactivation of bacterial cells through catalyzed oxidation using hydrogen peroxide as the primary oxidant agent is dependent on a series of factors, such as the concentration of the catalyst, the rate of hydroxyl radical formation in the controlled decomposition of the oxidant agent, and the concentration and toxicity of hydrogen peroxide. The objective of this study was to develop a mathematical model able to predict the kinetics of the inactivation Escherichia coli and total coliforms cells present in treated domestic sewage through catalytic peroxidation. The catalyst used was iron oxide supported on mineral coal (called CP), and the effects of the operational conditions, including hydrogen peroxide concentration and dosage of catalyst, were evaluated. The results showed that the disinfection kinetics of the treated domestic sewage is dependent on the concentrations of hydrogen peroxide and catalyst dosage. The kinetic model was shown to be able to predict the behavior of the inactivation kinetics of the bacterium Escherichia coli ATCC-25922 when different concentrations of hydrogen peroxide (75 and 100 mg·L^-1) were used, regardless of the catalyst dosage.
基金Supported by the National Key Basic Research Program of China(2013CB733505,2013CB733501)the National Natural Science Foundation of China(91334202)+2 种基金the Natural Science Foundation of Jiangsu Province of China(BK2012421,BK20130062)the Research Fund for the Doctoral Program of Higher Education of China(20123221120015)the Project for Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘The use of nanostructured composites as catalyst supports is a promising route to prepare catalysts with high selectivity and productivity. In this work, reduced graphene oxide-TiO_2(rGP-x) composites with a variation of reduced graphene oxide(rGO) content were synthesized by hydrothermal method. Pd/rGP-x catalysts were prepared in incipient-wetness impregnation method for the direct synthesis of H_2O_2 from H2 and O_2. The morphology and electronic properties of catalysts were investigated by XPS, TEM, and Raman spectroscopy.The ratio of Pd^(2+)/Pd^0 and the hydrophobicity of the catalysts were increased with the rising content of rGO. As the amount of rGO in the catalysts varied in the range of 0.025 wt%–2 wt%, the selectivity of H_2O_2 exhibited a tendency of increasing firstly and then decreasing from 0.1 wt% to 2 wt%. It indicates that good catalytic performance for H_2O_2 synthesis can be achieved only when appropriate amount of rGO is introduced. The H_2O_2 selectivity and productivity of Pd/r GP-0.025 both improved remarkably compared with Pd/P25. This enhancement originated from the combined effects of the proper ratio of Pd^(2+)/Pd^0 and hydrophobicity of the catalyst.