The catalytic hydrogenation of p-nitrophenol to p-aminophenol was investigated over Ni/Al2O3 catalyst on alumina support with different particle size. It is found that support particle size has significant influences ...The catalytic hydrogenation of p-nitrophenol to p-aminophenol was investigated over Ni/Al2O3 catalyst on alumina support with different particle size. It is found that support particle size has significant influences on physiochemical properties and catalytic activity of the resulting Ni/Al2O3 catalyst, but little influence on the selec-tivity. At a comparable amount of Ni loading, the catalytic activity of Ni/Al2O3 prepared with alumina support of smaller particle size is lower. The reduction behavior of the catalyst is a key factor in determining the catalytic activity of Ni/Al2O3 catalyst. The supported nickel catalyst 10.3Ni/Al2O3-3 improves the life span of the membrane by reducing fouling on the membrane surface compared to nano-sized nickel.展开更多
Pre-treatment, which supplies a stable, high-quality feed for reverse osmosis （RO） membranes, is a criti- cal step for successful operation in a seawater reverse osmosis plant. In this study, ceramic membrane system...Pre-treatment, which supplies a stable, high-quality feed for reverse osmosis （RO） membranes, is a criti- cal step for successful operation in a seawater reverse osmosis plant. In this study, ceramic membrane systems were employed as pre-treatment for seawater desalination. A laboratory experiment was performed to investigate the effect of the cross-flow velocity on the critical flux and consequently to optimize the permeate flux. Then a pilot test was performed to investigate the long-term performance. The result shows that there is no significant effect of the cross-flow velocity on the critical flux when the cross-flow velocity varies in laminar flow region only or in turbulent flow region only, but the effect is distinct when the cross-flow velocity varies in the transition region. The membrane fouling is slight at the permeate flux of 150 L·m^-2·h^-1 and the system is stable, producing a high-quality feed （the turbidity and silt density index are less than 0.1 NTU and 3.0, respectively） for RO to run for 2922.4 h without chemical cleaning. Thus the ceramic membranes are suitable to filtrate seawater as the pre-treatment for RO.展开更多
基金Supported by the Special Funds for Major State Basic Research Program of China （No.2003CB615702）, the National Natural Science Foundation of China （No.20636020） and the Natural Science Foundation of Jiangsu Province （No.BK2006722）.
文摘The catalytic hydrogenation of p-nitrophenol to p-aminophenol was investigated over Ni/Al2O3 catalyst on alumina support with different particle size. It is found that support particle size has significant influences on physiochemical properties and catalytic activity of the resulting Ni/Al2O3 catalyst, but little influence on the selec-tivity. At a comparable amount of Ni loading, the catalytic activity of Ni/Al2O3 prepared with alumina support of smaller particle size is lower. The reduction behavior of the catalyst is a key factor in determining the catalytic activity of Ni/Al2O3 catalyst. The supported nickel catalyst 10.3Ni/Al2O3-3 improves the life span of the membrane by reducing fouling on the membrane surface compared to nano-sized nickel.
基金Supported by the National High Technology Research and Development of China (2007AA030303)
文摘Pre-treatment, which supplies a stable, high-quality feed for reverse osmosis （RO） membranes, is a criti- cal step for successful operation in a seawater reverse osmosis plant. In this study, ceramic membrane systems were employed as pre-treatment for seawater desalination. A laboratory experiment was performed to investigate the effect of the cross-flow velocity on the critical flux and consequently to optimize the permeate flux. Then a pilot test was performed to investigate the long-term performance. The result shows that there is no significant effect of the cross-flow velocity on the critical flux when the cross-flow velocity varies in laminar flow region only or in turbulent flow region only, but the effect is distinct when the cross-flow velocity varies in the transition region. The membrane fouling is slight at the permeate flux of 150 L·m^-2·h^-1 and the system is stable, producing a high-quality feed （the turbidity and silt density index are less than 0.1 NTU and 3.0, respectively） for RO to run for 2922.4 h without chemical cleaning. Thus the ceramic membranes are suitable to filtrate seawater as the pre-treatment for RO.
