A long chain aliphatic sulfoxide can be used as an extractant.It can extract almost all metallic ions which can be extracted by tributylphosphate (TBP).The extraction of gold was studied by Chekushin,V. S. and Mojski,...A long chain aliphatic sulfoxide can be used as an extractant.It can extract almost all metallic ions which can be extracted by tributylphosphate (TBP).The extraction of gold was studied by Chekushin,V. S. and Mojski,M.using petroleum sulfoxide and n-dioctyl sulfoxide(DOSO) as an extractant respectively.展开更多
Highly hydrophobic Di 2-ethyl hexyl phthalate（DEHP） is one of the most prevalent plasticizers in wastewaters. Since its half-life in biological treatment is around 25 days, it can be used as an efficiency indicator ...Highly hydrophobic Di 2-ethyl hexyl phthalate（DEHP） is one of the most prevalent plasticizers in wastewaters. Since its half-life in biological treatment is around 25 days, it can be used as an efficiency indicator of wastewater treatment plant for the removal of hydrophobic emerging contaminants. In this study, the performance of submerged membrane bioreactor was monitored to understand the effect of DEHP on the growth of aerobic microorganisms. The data showed that the chemical oxygen demand（COD）and ammonia concentration were detected below 10 and 1.0 mg/L, respectively for operating conditions of hydraulic retention time（HRT） = 4 and 6 hr, sludge retention time（SRT） = 140 day and sludge concentration between 11.5 and 15.8 g volatile solid（VS）/L. The removal efficiency of DEHP under these conditions was higher and ranged between 91% and 98%. Results also showed that the removal efficiency of DEHP in biological treatment depended on the concentration of sludge, as adsorption is the main mechanism of its removal. For the submerged membrane bioreactor, the pore size is the pivotal factor for DEHP removal, since it determines the amount of soluble microbial products coming out of the process. Highly assimilated microorganisms increase the biodegradation rate, as 74% of inlet DEHP was biodegraded; however, the concentration of DEHP inside sludge was beyond the discharge limit. Understanding the fate of DEHP in membrane bioreactor,which is one of the most promising and futuristic treatment process could provide replacement for conventional processes to satisfy the future stricter regulations on emerging contaminants.展开更多
The transport of Dy（III） through a dispersion supported liquid membrane （DSLM） consisting of polyvinylidene fluoride membrane （PVDF） as the liquid membrane support and dispersion solution including HCI solution ...The transport of Dy（III） through a dispersion supported liquid membrane （DSLM） consisting of polyvinylidene fluoride membrane （PVDF） as the liquid membrane support and dispersion solution including HCI solution as the stripping solution and 2-ethyl hexyl phosphonic acid-mono-2-ethyl hexyl ester （PC-88A） dissolved in kerosene as the membrane solution, was studied. The effects of pH value, initial concentration of Dy（III） and different ionic strength in the feed phase, volume ratio of membrane solution and stripping solution, concentration of HCl solution, concentration of carrier, different stripping agents in the dispersion phase on transport of Dy（III） were also investigated, respectively. As a result, when the concentration of HCI solution was 4.0 mol/L, concentration of PC-88A was 0.10 mol/L, and volume ratio of membrane solution and stripping solution was 40：20 in the dispersion phase, and pH value was 5.0 in the feed phase, the transport effect of Dy（III） was the best. Ionic strength had no obvious effect on transport of Dy（III）. Under the optimum condition studied, when initial concentration of Dy（III） was 0.8×10^-4 mol/L, the transport rate of Dy（III） was up to 96.2% during the transport time of 95 rain. The kinetic equation was developed in terms of the law of mass diffusion and the theory of interface chemistry. The diffusion coefficient of Dy（III） in the membrane and the thickness of diffusion layer between feed phase and membrane phase were obtained and the values were 1.99×10^-7 m^2/s and 15.97 μm, respectively. The results were in good agreement with experimental results.展开更多
The process for removal of samarium from NdCl_3 solution containing a little samarium by solvent extrac-tion with unsaponated Di (2-ethyl hexyl) orthosphoric acid (DEHPA) at acidic range is reported. The in-dustri...The process for removal of samarium from NdCl_3 solution containing a little samarium by solvent extrac-tion with unsaponated Di (2-ethyl hexyl) orthosphoric acid (DEHPA) at acidic range is reported. The in-dustrial experiments have been completed on a production line of 150 t Nd_2O_3 per annum in the Baotou ThirdRare Earth Factory. As a result of 9 step counter current extraction , Sm_2 O_3 content in Nd_2 O_3 drops down to0. 08 % from 0. 5% , the purity of neodymium oxide is over 99. 5% and the direct recovery of Nd_2O_3 is 92%～ 93% .展开更多
A novel kind of supported combined liquid membrane （SCLM） has been studied for the Gd（IIl） transfer. SCLM contained polyvinylidene fluoride membrane （PVDF） as the liquid membrane support and renewal solution inc...A novel kind of supported combined liquid membrane （SCLM） has been studied for the Gd（IIl） transfer. SCLM contained polyvinylidene fluoride membrane （PVDF） as the liquid membrane support and renewal solution including HNO3 solution as the stripping solution and 2-ethyl hexyl phosphonic acid-mono-2-ethyl hexyl ester （HEH（EH）P） as the carrier dissolved in kerosene. The mixed solution of carrier and kerosene was membrane solution. The optimum transport conditions of Gd（III） were that concentration of HNO3 solution was 4.00 tool/L, concentration of carrier was 0.16 mol/L, and volume ratio of membrane solution to stripping solution was 30：30 of the renewal phase, and pH value was 4.80 of the feed phase. Under the optimum condition studied, when initial concentration of Gd（III） was 1.00 × 10^-4 mol/L, the transfer rate of Gd（III） was 96.8% during 130 min.展开更多
A mathematical model for the transport of Ce （IV） from hydrochloric acid solutions through dispersion flat combined liquid membrane （DFCLM） with contain 2- ethyl hexyl phosphonic acid-mono-2-ethyl hexyl ester （P...A mathematical model for the transport of Ce （IV） from hydrochloric acid solutions through dispersion flat combined liquid membrane （DFCLM） with contain 2- ethyl hexyl phosphonic acid-mono-2-ethyl hexyl ester （P507） as the carrier, dissolved in kerosene as the membrane solution have been studied. This process of facilitated transport, based on membrane technology, is a variation on the conventional technique of solvent extraction and may be described mathematically using Fick＇s second law. The equations for transport velocity are derived considering the diffusion of P507 and its metallic complexes through the liquid membrane. In this work, the system is considered to be in a transient state, and chemical reaction between Ce（IV） and the carrier to take place only at the solvent-aqueous interfaces. Model concentration profiles are obtained for the Ce（IV）, from which extraction velocities are predicted. The experimental and simulated Ce（IV） extractions showed similar tendencies for a high Ce （IV） concentration and acidity case.The model results indicate that high initial Ce（IV） concentrations and acidity both have detrimental effects on Ce（IV） extraction and stripping. The diffusion coefficient of Ce（IV） in the membrane and the thickness of diffusion layer between feed phase and membrane phase are obtained and the values are 6.31 × 10-8m2·s-1 and 31.2 μm, respectively. The results are in good agreement with experimental results.展开更多
Stripping dispersion hollow fiber liquid membrane system（SDHFLM） containing feed phase adding acetate buffer solution and dispersion solution with HNO_3 solution as the stripping solution and membrane solution of 2-...Stripping dispersion hollow fiber liquid membrane system（SDHFLM） containing feed phase adding acetate buffer solution and dispersion solution with HNO_3 solution as the stripping solution and membrane solution of 2-ethyl hexyl phosphoric acid-mono-2-ethylhexyl ester（PC-88A） dissolved in kerosene,has been studied for the extraction of Sm^（3＋）.Many factors including pH value, volume ratio of membrane solution to stripping solution（OAV） and carrier concentration on Sm^（3＋） extraction were investigated. Experimental results indicate that the optimum extraction conditions of Sm^（3＋） were obtained as that PC-88A concentration was 0.120 mol/L,and OAV was 1.00 in the dispersion phase,and pH value was 4.80 in the feed phase.When initial Sm^（3＋） concentration was 1.20×10^（-4） mol/L,the extraction percentage of Sm^（3＋） was up to 92.8%in 160 min.展开更多
基金Projects supported by the Fund of National Natural Science Foundation
文摘A long chain aliphatic sulfoxide can be used as an extractant.It can extract almost all metallic ions which can be extracted by tributylphosphate (TBP).The extraction of gold was studied by Chekushin,V. S. and Mojski,M.using petroleum sulfoxide and n-dioctyl sulfoxide(DOSO) as an extractant respectively.
基金the National Sciences and Engineering Research Council of Canada (NSERC Grant Number: I2IPJ 461378)
文摘Highly hydrophobic Di 2-ethyl hexyl phthalate（DEHP） is one of the most prevalent plasticizers in wastewaters. Since its half-life in biological treatment is around 25 days, it can be used as an efficiency indicator of wastewater treatment plant for the removal of hydrophobic emerging contaminants. In this study, the performance of submerged membrane bioreactor was monitored to understand the effect of DEHP on the growth of aerobic microorganisms. The data showed that the chemical oxygen demand（COD）and ammonia concentration were detected below 10 and 1.0 mg/L, respectively for operating conditions of hydraulic retention time（HRT） = 4 and 6 hr, sludge retention time（SRT） = 140 day and sludge concentration between 11.5 and 15.8 g volatile solid（VS）/L. The removal efficiency of DEHP under these conditions was higher and ranged between 91% and 98%. Results also showed that the removal efficiency of DEHP in biological treatment depended on the concentration of sludge, as adsorption is the main mechanism of its removal. For the submerged membrane bioreactor, the pore size is the pivotal factor for DEHP removal, since it determines the amount of soluble microbial products coming out of the process. Highly assimilated microorganisms increase the biodegradation rate, as 74% of inlet DEHP was biodegraded; however, the concentration of DEHP inside sludge was beyond the discharge limit. Understanding the fate of DEHP in membrane bioreactor,which is one of the most promising and futuristic treatment process could provide replacement for conventional processes to satisfy the future stricter regulations on emerging contaminants.
基金supported by the National Natural Science Foundation of China (90401009)Research Fund for Excellent Doctoral Thesis of Xi'an University of Technology (602-210805)
文摘The transport of Dy（III） through a dispersion supported liquid membrane （DSLM） consisting of polyvinylidene fluoride membrane （PVDF） as the liquid membrane support and dispersion solution including HCI solution as the stripping solution and 2-ethyl hexyl phosphonic acid-mono-2-ethyl hexyl ester （PC-88A） dissolved in kerosene as the membrane solution, was studied. The effects of pH value, initial concentration of Dy（III） and different ionic strength in the feed phase, volume ratio of membrane solution and stripping solution, concentration of HCl solution, concentration of carrier, different stripping agents in the dispersion phase on transport of Dy（III） were also investigated, respectively. As a result, when the concentration of HCI solution was 4.0 mol/L, concentration of PC-88A was 0.10 mol/L, and volume ratio of membrane solution and stripping solution was 40：20 in the dispersion phase, and pH value was 5.0 in the feed phase, the transport effect of Dy（III） was the best. Ionic strength had no obvious effect on transport of Dy（III）. Under the optimum condition studied, when initial concentration of Dy（III） was 0.8×10^-4 mol/L, the transport rate of Dy（III） was up to 96.2% during the transport time of 95 rain. The kinetic equation was developed in terms of the law of mass diffusion and the theory of interface chemistry. The diffusion coefficient of Dy（III） in the membrane and the thickness of diffusion layer between feed phase and membrane phase were obtained and the values were 1.99×10^-7 m^2/s and 15.97 μm, respectively. The results were in good agreement with experimental results.
文摘The process for removal of samarium from NdCl_3 solution containing a little samarium by solvent extrac-tion with unsaponated Di (2-ethyl hexyl) orthosphoric acid (DEHPA) at acidic range is reported. The in-dustrial experiments have been completed on a production line of 150 t Nd_2O_3 per annum in the Baotou ThirdRare Earth Factory. As a result of 9 step counter current extraction , Sm_2 O_3 content in Nd_2 O_3 drops down to0. 08 % from 0. 5% , the purity of neodymium oxide is over 99. 5% and the direct recovery of Nd_2O_3 is 92%～ 93% .
基金supported by the Foundation for Planning project of West Action of Chinese Academy of Sciences(No.KZCX2-XB2-13)the National Natural Science Foundation of China for Young Scientists(No. 41001131+2 种基金No.51009126)Research Fund for Excellent Doctoral Thesis of Xi'an University of Technology(No. 602-210805No.602-210804)
文摘A novel kind of supported combined liquid membrane （SCLM） has been studied for the Gd（IIl） transfer. SCLM contained polyvinylidene fluoride membrane （PVDF） as the liquid membrane support and renewal solution including HNO3 solution as the stripping solution and 2-ethyl hexyl phosphonic acid-mono-2-ethyl hexyl ester （HEH（EH）P） as the carrier dissolved in kerosene. The mixed solution of carrier and kerosene was membrane solution. The optimum transport conditions of Gd（III） were that concentration of HNO3 solution was 4.00 tool/L, concentration of carrier was 0.16 mol/L, and volume ratio of membrane solution to stripping solution was 30：30 of the renewal phase, and pH value was 4.80 of the feed phase. Under the optimum condition studied, when initial concentration of Gd（III） was 1.00 × 10^-4 mol/L, the transfer rate of Gd（III） was 96.8% during 130 min.
基金This research was supported by the National Natural Science Foundation of China for Young Scientists （Grant No. 51109197）, the Fnndation for Planning project of West Action of Chinese Academy of Sciences CKZCX2-XB2-13） and Research Fund for Excellent Doctoral Thesis of Xi＇an University of Technology （602-210805）.
文摘A mathematical model for the transport of Ce （IV） from hydrochloric acid solutions through dispersion flat combined liquid membrane （DFCLM） with contain 2- ethyl hexyl phosphonic acid-mono-2-ethyl hexyl ester （P507） as the carrier, dissolved in kerosene as the membrane solution have been studied. This process of facilitated transport, based on membrane technology, is a variation on the conventional technique of solvent extraction and may be described mathematically using Fick＇s second law. The equations for transport velocity are derived considering the diffusion of P507 and its metallic complexes through the liquid membrane. In this work, the system is considered to be in a transient state, and chemical reaction between Ce（IV） and the carrier to take place only at the solvent-aqueous interfaces. Model concentration profiles are obtained for the Ce（IV）, from which extraction velocities are predicted. The experimental and simulated Ce（IV） extractions showed similar tendencies for a high Ce （IV） concentration and acidity case.The model results indicate that high initial Ce（IV） concentrations and acidity both have detrimental effects on Ce（IV） extraction and stripping. The diffusion coefficient of Ce（IV） in the membrane and the thickness of diffusion layer between feed phase and membrane phase are obtained and the values are 6.31 × 10-8m2·s-1 and 31.2 μm, respectively. The results are in good agreement with experimental results.
基金financially supported by the National Natural Science Foundation of China for Young Scientists(Nos. 51109197 and 51009126)the Action Plan for the Development of Western China of the Chinese Academy of Sciences (No.KZCX2-XB2-13)+1 种基金the Knowledge Innovation Program of the Chinese Academy of Sciences(No.KSCX2-YW-N -003)Research Fund for Excellent Doctoral Thesis of Xi'an University of Technology(Nos.602-210805 and 602-210804)
文摘Stripping dispersion hollow fiber liquid membrane system（SDHFLM） containing feed phase adding acetate buffer solution and dispersion solution with HNO_3 solution as the stripping solution and membrane solution of 2-ethyl hexyl phosphoric acid-mono-2-ethylhexyl ester（PC-88A） dissolved in kerosene,has been studied for the extraction of Sm^（3＋）.Many factors including pH value, volume ratio of membrane solution to stripping solution（OAV） and carrier concentration on Sm^（3＋） extraction were investigated. Experimental results indicate that the optimum extraction conditions of Sm^（3＋） were obtained as that PC-88A concentration was 0.120 mol/L,and OAV was 1.00 in the dispersion phase,and pH value was 4.80 in the feed phase.When initial Sm^（3＋） concentration was 1.20×10^（-4） mol/L,the extraction percentage of Sm^（3＋） was up to 92.8%in 160 min.
