A series of CeO2‐MnOx‐Al2O3 mixed oxide catalysts （Ce：Mn：Al mole ratio=6：4：x, x=0.25, 0.5, 1, 2） were prepared by a simple one‐step inverse co‐precipitation method to investigate the influence of the incorpo...A series of CeO2‐MnOx‐Al2O3 mixed oxide catalysts （Ce：Mn：Al mole ratio=6：4：x, x=0.25, 0.5, 1, 2） were prepared by a simple one‐step inverse co‐precipitation method to investigate the influence of the incorporation of Al3＋ into CeO2‐MnOx mixed oxides. CeO2‐MnOx, CeO2‐Al2O3, and MnOx‐Al2O3 mixed oxides, and CeO2 were prepared by the same method for comparison. The samples were characterized by XRD, Raman, N2 physisorption, H2‐TPR, XPS, and in situ DRIFTS. The catalytic re‐duction of NO by CO was chosen as a model reaction to evaluate the catalytic performance. The incorporation of a small amount of Al3＋into CeO2‐MnOx mixed oxides resulted in a decrease of crys‐tallite size, with the increase of the BET specific surface area and pore volume, as well as the in‐crease of Ce3＋and Mn4＋. The former benefits good contact between catalyst and reactants, and the latter promotes the adsorption of CO and the desorption, conversion and dissociation of adsorbed NO. All these enhanced the catalytic performance for the NO＋CO model reaction. A reaction mecha‐nism was proposed to explain the excellent catalytic performance of CeO2‐MnOx‐Al2O3 catalysts for NO reduction by CO.展开更多
The effect of rhamnolipids （RL） on Cd^2＋ adsorption by Penicillium simplicissimum （P. simplicissimum） was studied. The maximum adsorption capacities of Cd^2＋ were obtained at pH 6.0 for the intact P. sirnpliciss...The effect of rhamnolipids （RL） on Cd^2＋ adsorption by Penicillium simplicissimum （P. simplicissimum） was studied. The maximum adsorption capacities of Cd^2＋ were obtained at pH 6.0 for the intact P. sirnplicissimurn and at pH 5.0 for the RL-pretreated P. simplicissimum, respectively. The adsorption equilibrium was reached after about 4 h. The experimental adsorption isotherms were in good agreement with the Langmuir model. The maximum adsorption capacities （qmax） for the intact P. simplicissimurn and for the RL-pretreated P. simplicissimum were 51.6 and 70.4 rag/g, respectively. The interactions between Cd^2＋ and functional groups on the cell wall surface of the P. simplicissimum were identified by SEM, EDAX and FTIR analysis. It is indicated that carboxyl, amino and hydroxyl groups play major roles in the Cd^2＋ adsorption. The results suggest that the RL-pretreated P. simplicissimum is a promising candidate for the removal of Cd^2＋ from aqueous solutions.展开更多
基金supported by the National Natural Science Foundation of China (21507130)the Open Project Program of Chongqing Key Laboratory of Environmental Materials and Remediation Technology from Chongqing University of Arts and Sciences (CEK1405)+3 种基金the Open Project Program of Beijing National Laboratory for Molecular Sciences (20140142)the Open Project Program of Jiangsu Key Laboratory of Vehicle Emissions Control (OVEC001)the Open Project Program of Chongqing Key Laboratory of Catalysis and Functional Organic Molecules from Chongqing Technology and Business University (1456029)the Chongqing Science & Technology Commission (cstc2014pt-gc20002)~~
文摘A series of CeO2‐MnOx‐Al2O3 mixed oxide catalysts （Ce：Mn：Al mole ratio=6：4：x, x=0.25, 0.5, 1, 2） were prepared by a simple one‐step inverse co‐precipitation method to investigate the influence of the incorporation of Al3＋ into CeO2‐MnOx mixed oxides. CeO2‐MnOx, CeO2‐Al2O3, and MnOx‐Al2O3 mixed oxides, and CeO2 were prepared by the same method for comparison. The samples were characterized by XRD, Raman, N2 physisorption, H2‐TPR, XPS, and in situ DRIFTS. The catalytic re‐duction of NO by CO was chosen as a model reaction to evaluate the catalytic performance. The incorporation of a small amount of Al3＋into CeO2‐MnOx mixed oxides resulted in a decrease of crys‐tallite size, with the increase of the BET specific surface area and pore volume, as well as the in‐crease of Ce3＋and Mn4＋. The former benefits good contact between catalyst and reactants, and the latter promotes the adsorption of CO and the desorption, conversion and dissociation of adsorbed NO. All these enhanced the catalytic performance for the NO＋CO model reaction. A reaction mecha‐nism was proposed to explain the excellent catalytic performance of CeO2‐MnOx‐Al2O3 catalysts for NO reduction by CO.
基金Project(50978087) supported by the National Natural Science Foundation of ChinaProject(CX2010B157) supported by the Hunan Provincial Innovation Foundation for Postgraduate,China
文摘The effect of rhamnolipids （RL） on Cd^2＋ adsorption by Penicillium simplicissimum （P. simplicissimum） was studied. The maximum adsorption capacities of Cd^2＋ were obtained at pH 6.0 for the intact P. sirnplicissimurn and at pH 5.0 for the RL-pretreated P. simplicissimum, respectively. The adsorption equilibrium was reached after about 4 h. The experimental adsorption isotherms were in good agreement with the Langmuir model. The maximum adsorption capacities （qmax） for the intact P. simplicissimurn and for the RL-pretreated P. simplicissimum were 51.6 and 70.4 rag/g, respectively. The interactions between Cd^2＋ and functional groups on the cell wall surface of the P. simplicissimum were identified by SEM, EDAX and FTIR analysis. It is indicated that carboxyl, amino and hydroxyl groups play major roles in the Cd^2＋ adsorption. The results suggest that the RL-pretreated P. simplicissimum is a promising candidate for the removal of Cd^2＋ from aqueous solutions.
