A series of manganese-cerium oxide catalysts were prepared by different methods and used for low-temperature catalytic oxidation of NO in the presence of excess O2.Their surface properties were evaluated by means of B...A series of manganese-cerium oxide catalysts were prepared by different methods and used for low-temperature catalytic oxidation of NO in the presence of excess O2.Their surface properties were evaluated by means of BET and were characterized by using scanning electron microscopy(SEM) and X-ray diffractometer(XRD).The activity test of Mn-Ce-Ox catalysts showed that addition of Ce enhanced the activities of NO oxidation.The most active catalysts with a molar Ce/(Mn+Ce) ratio of 0.3 were prepared by co-precip...展开更多
A series of Mn-based catalysts, MnOx, MnOx-CeO, Pd-Mn-Ce, MnOx/AC were prepared. And their performances for NO low-temperature SCR were investigated in this study. The NO conversion is about 90% at 100 ℃ on MnOx-CeOa...A series of Mn-based catalysts, MnOx, MnOx-CeO, Pd-Mn-Ce, MnOx/AC were prepared. And their performances for NO low-temperature SCR were investigated in this study. The NO conversion is about 90% at 100 ℃ on MnOx-CeOand almost all NO can be converted at 120 ℃. Similar results are also observed in the tests on MnOx-CeO/AC. The excellent low-temperature catalytic activity of modified Mn-based catalysts, which may be mainly due to the oxygen storage function of CeO, can improve the oxygen flow on the catalysts surface. Then the oxidation of NO to NO2 is accelerated, which is the key step of NO SCR.展开更多
For the goal of sulfur recovery, most methods are aimed at the tail gas with high-concentration H2S, but few effective methods are used for low-concentration H2S. In this work, Low-concentration H2S could be purified ...For the goal of sulfur recovery, most methods are aimed at the tail gas with high-concentration H2S, but few effective methods are used for low-concentration H2S. In this work, Low-concentration H2S could be purified well by liquid phase catalytic oxidation (LCO), and the sulfur resource could also be recovered. The absorption solution was prepared by FeCl3 and sulfosalicylic acid. Under the experimental conditions, the conversion of H2S to S could be maintained above 94% at 60 ℃. In order to enhance the economical efficiency of LCO method, the absorption solution was modified by doping Ce, and a series of experiments were designed to investigate its performance. The results showed that the conversion of H2S had no obvious improvement, but above 98% conversion could be gained at 60 ℃, and the H2S conversion rate was enhanced. The optimum addition quality of Ce(NO3)3 was 0.08 g to 50 ml Fe3+ solution.展开更多
ByBimolecular Nucleophilic Substitution, four new types of alkylene triphenyl double quaternary phosphonium salt were synthesized respectively by using triphenylphosphine, 1,3-dibromopropane, 1,6-dibromohexane,1,10-di...ByBimolecular Nucleophilic Substitution, four new types of alkylene triphenyl double quaternary phosphonium salt were synthesized respectively by using triphenylphosphine, 1,3-dibromopropane, 1,6-dibromohexane,1,10-dibromo- decane, 1,12-dibromododecane as raw materials and using DMAC as the solvent, under a certain temperature and reac- tion time. The productivity is 58% - 83%. The molecular structures of the products were characterized by IR, NMR and elemental analysis. The sterilizing effect of 1,6-hexylidene triphenyl double phosphonium bromide(HTDPB) and 1,12- dodecylidene triphenyl double phosphonium bromide(DoTDPB) was evaluated by using extinct dilution method.The experimental result shows that the sterilizing effect of DoTDPB is better than the effect of HTDPB under the same drug concentration and contact time. When the concentration of DoTDPB was 20 mg/L and the contact time was 0.5 h, the sterilizing rate of DoTDPB used to kill saprophytic bacteria (TGB), sulfate-reducing bacteria (SRB) and iron bacteria (IB) was 95.56%, 84% and 99.58% respectively.展开更多
Hydrogen sulfide in rural biogas was removed with liquid-phase catalytic oxidation.By using rare earth as catalyst,and sulfosalicylic acid as stabilizer,H2S purification efficiency could increase as high as 96%,and su...Hydrogen sulfide in rural biogas was removed with liquid-phase catalytic oxidation.By using rare earth as catalyst,and sulfosalicylic acid as stabilizer,H2S purification efficiency could increase as high as 96%,and sulfur capacity of the composite solution was about 3 g/L.The results show that purification efficiency was affected by catalyst addition,pH,experimental temperature,and sulfur capacity.The parameters effects on catalytic oxidation were studied,and the optimized conditions were that Fe3+ concentration 0.08 mg/L,reaction temperature 70°C,pH 9.0,with a absorption solution volume of 50 mL,a gas flow rate 200 mL/min,and H2S mass concentration of 1.58-2.02 mg/m3.展开更多
The concentration and chemical speciation of metal elements(K,Na,Ca,Mg and Sr) in sediments were investigated from upstream of the Pearl River,China.The result showed that Total concentrations of metal elements in sed...The concentration and chemical speciation of metal elements(K,Na,Ca,Mg and Sr) in sediments were investigated from upstream of the Pearl River,China.The result showed that Total concentrations of metal elements in sediments were in wide range,the ranges of K,Na,Ca,Mg and Sr were 3 016-12 742,135-565,6 794-12 968,2 060-6 229 and 4.01-35.4 mg/kg in sediments.K was dominated by the residual fraction,Sr was dominated by weak acid soluble fraction.The bioavailability of Sr in the area is higher than K.The order of bioavailability was Sr>Na>Ca>Mg>K.展开更多
基金supported by National Natural Science Foundation of China (20907018)Natural Science Foundation of Yunnan Province (2007E184M)+1 种基金Education Department Scientific Research Foundation of Yunnan Province (07C11400)Young and Middle-aged Academic and Technical Back-up Personnel Program of Yunnan Province (2008PY009)
文摘A series of manganese-cerium oxide catalysts were prepared by different methods and used for low-temperature catalytic oxidation of NO in the presence of excess O2.Their surface properties were evaluated by means of BET and were characterized by using scanning electron microscopy(SEM) and X-ray diffractometer(XRD).The activity test of Mn-Ce-Ox catalysts showed that addition of Ce enhanced the activities of NO oxidation.The most active catalysts with a molar Ce/(Mn+Ce) ratio of 0.3 were prepared by co-precip...
基金the Key Project of the National Natural Science Foundation of China (20437010)the Natural Science Foundation of Yunnan Province (2007E184M)the Science Foundation of the Education Department of Yunnan Province(07C11400)
文摘A series of Mn-based catalysts, MnOx, MnOx-CeO, Pd-Mn-Ce, MnOx/AC were prepared. And their performances for NO low-temperature SCR were investigated in this study. The NO conversion is about 90% at 100 ℃ on MnOx-CeOand almost all NO can be converted at 120 ℃. Similar results are also observed in the tests on MnOx-CeO/AC. The excellent low-temperature catalytic activity of modified Mn-based catalysts, which may be mainly due to the oxygen storage function of CeO, can improve the oxygen flow on the catalysts surface. Then the oxidation of NO to NO2 is accelerated, which is the key step of NO SCR.
基金the Natural Science Foundation of Yunnan Province (2001E0011Q)the Science Foundation of The Education Department of Yunnan Province (0142111 and 07Z11402)
文摘For the goal of sulfur recovery, most methods are aimed at the tail gas with high-concentration H2S, but few effective methods are used for low-concentration H2S. In this work, Low-concentration H2S could be purified well by liquid phase catalytic oxidation (LCO), and the sulfur resource could also be recovered. The absorption solution was prepared by FeCl3 and sulfosalicylic acid. Under the experimental conditions, the conversion of H2S to S could be maintained above 94% at 60 ℃. In order to enhance the economical efficiency of LCO method, the absorption solution was modified by doping Ce, and a series of experiments were designed to investigate its performance. The results showed that the conversion of H2S had no obvious improvement, but above 98% conversion could be gained at 60 ℃, and the H2S conversion rate was enhanced. The optimum addition quality of Ce(NO3)3 was 0.08 g to 50 ml Fe3+ solution.
文摘ByBimolecular Nucleophilic Substitution, four new types of alkylene triphenyl double quaternary phosphonium salt were synthesized respectively by using triphenylphosphine, 1,3-dibromopropane, 1,6-dibromohexane,1,10-dibromo- decane, 1,12-dibromododecane as raw materials and using DMAC as the solvent, under a certain temperature and reac- tion time. The productivity is 58% - 83%. The molecular structures of the products were characterized by IR, NMR and elemental analysis. The sterilizing effect of 1,6-hexylidene triphenyl double phosphonium bromide(HTDPB) and 1,12- dodecylidene triphenyl double phosphonium bromide(DoTDPB) was evaluated by using extinct dilution method.The experimental result shows that the sterilizing effect of DoTDPB is better than the effect of HTDPB under the same drug concentration and contact time. When the concentration of DoTDPB was 20 mg/L and the contact time was 0.5 h, the sterilizing rate of DoTDPB used to kill saprophytic bacteria (TGB), sulfate-reducing bacteria (SRB) and iron bacteria (IB) was 95.56%, 84% and 99.58% respectively.
基金Project(2008ZX07105-002) supported by the Erhai Lake Project of National Science and Technology Major Project in the 11th Five years Plan of China
文摘Hydrogen sulfide in rural biogas was removed with liquid-phase catalytic oxidation.By using rare earth as catalyst,and sulfosalicylic acid as stabilizer,H2S purification efficiency could increase as high as 96%,and sulfur capacity of the composite solution was about 3 g/L.The results show that purification efficiency was affected by catalyst addition,pH,experimental temperature,and sulfur capacity.The parameters effects on catalytic oxidation were studied,and the optimized conditions were that Fe3+ concentration 0.08 mg/L,reaction temperature 70°C,pH 9.0,with a absorption solution volume of 50 mL,a gas flow rate 200 mL/min,and H2S mass concentration of 1.58-2.02 mg/m3.
基金Supported by the Educational Commission of Yunnan Province of China(2013Y119)the Key Scientific Research Foundation of Southwest Forestry University(111417)
文摘The concentration and chemical speciation of metal elements(K,Na,Ca,Mg and Sr) in sediments were investigated from upstream of the Pearl River,China.The result showed that Total concentrations of metal elements in sediments were in wide range,the ranges of K,Na,Ca,Mg and Sr were 3 016-12 742,135-565,6 794-12 968,2 060-6 229 and 4.01-35.4 mg/kg in sediments.K was dominated by the residual fraction,Sr was dominated by weak acid soluble fraction.The bioavailability of Sr in the area is higher than K.The order of bioavailability was Sr>Na>Ca>Mg>K.
基金Project supported by the National Natural Science Foundation of China(Nos.41303093,41222025,and 41273138)the Program for New Century Excellent Talents in University of Ministry of Education of Chinathe Recruitment Program of HighlyQualified Scholars in Yunnan Province(No.2010CI109),China
