A novel magnetic anion exchange resin NDM-1 was prepared through suspension polymerization and then functionalized with ammonolysis and alkylating agents.Its application for selective removal of nitrate was performed ...A novel magnetic anion exchange resin NDM-1 was prepared through suspension polymerization and then functionalized with ammonolysis and alkylating agents.Its application for selective removal of nitrate was performed in comparison with MIEX.The results demonstrated that NDM-1 achieved higher efficiency in nitrate removal than MIEX did,with or without the existence of competing anion SO_4^2- ascribed to its longer alkyl chains on exchange sites.Combined with the advantage of easy separation due toγ-Fe_2O_3 implanted,the magnetic anion exchange resin NDM-1 was considered to be superior to MIEX for nitrate removal in practical application.展开更多
Sorption recovery of palladium (II) from nitrate weak acidic model solutions and solutions of spent catalysts on some ion exchangers with different physical and chemical structure has been investigated. The palladium ...Sorption recovery of palladium (II) from nitrate weak acidic model solutions and solutions of spent catalysts on some ion exchangers with different physical and chemical structure has been investigated. The palladium concentration in contacting solutions was 5.0 ? 10-5 – 1.0 ? 10-3 mol/L at nitric acid and potassium nitrate con-centrations 0.01 and 1.0 mol/L, respectively. It was shown that anion exchangers AV-17-8 as well as Purolite S 985 and A 500 possess the best sorption and kinetic properties. These sorbents can be recommended for selective recovery of palladium from solutions of spent catalysts.展开更多
An anion exchange resin NDP-5 has been prepared successfully and applied on the selective removal of nitrate from SO_4^（2-）/ NO_3^- binary co-existence system.The composition and morphology of NDP-5 were confirmed b...An anion exchange resin NDP-5 has been prepared successfully and applied on the selective removal of nitrate from SO_4^（2-）/ NO_3^- binary co-existence system.The composition and morphology of NDP-5 were confirmed by FT-IR and SEM.The NDP-5 resin exhibits the completely different behavior on the adsorption capacity,adsorption kinetic and the effect of the completing anion in the absence or presence of sulfate,compared to D213.And,the resultants of kinetic are well fitted by the pseudo-first-order and pseudo-second-order models.These results are very important to develop novel resins with great features.展开更多
An improved method,suitable for collecting nitrate from surface waters in the watershed for 15 N isotope tracing analysis,was developed on the basis of the anion exchange coupled with diffusion through systematic simu...An improved method,suitable for collecting nitrate from surface waters in the watershed for 15 N isotope tracing analysis,was developed on the basis of the anion exchange coupled with diffusion through systematic simulation and comparison experiments.The results showed that the nitrate could be separated and enriched from the waters efficiently by using the improved method.Being simple and practical in operation principle and procedures,cost-economic,and highly efficient in nitrate separation/enrichment,the method met the requirements of δ 15 N mass spectrum analysis and would lay a foundation for the application of 15 N isotope tracing approach to the research on non-point source pollution in watershed.展开更多
选择新型强碱性阴离子交换树脂Amberlite IRA 402和Amberlite IRA 900,与201×7(717)树脂对比,进行吸附去除水中硝氮的实验研究。通过拟合3种树脂的控速步骤和动力学模型,研究吸附过程的动力学行为,并考虑了不同初始浓度的硝酸盐溶...选择新型强碱性阴离子交换树脂Amberlite IRA 402和Amberlite IRA 900,与201×7(717)树脂对比,进行吸附去除水中硝氮的实验研究。通过拟合3种树脂的控速步骤和动力学模型,研究吸附过程的动力学行为,并考虑了不同初始浓度的硝酸盐溶液、温度、溶解性有机质(DOM)、pH和转速等的影响。结果表明,IRA 402树脂对硝氮的吸附效果最好(吸附率99.3%),717次之(吸附率98.2%),IRA900稍弱(吸附率93%),但相差不大,且IRA402比较适合去除高浓度DOM废水的硝氮,没食子酸对硝氮去除的影响高于单宁酸。3种树脂吸附硝氮的过程主要受化学反应控制,并符合准二级动力学方程。温度的变化对3种树脂吸附硝氮的行为影响不是很大,可以选择在室温下(25℃)进行。在pH 7.0时,3种树脂吸附硝氮的效果最好,树脂吸附硝氮的转速可设置为200 r/min。展开更多
Research and development of green oxidizers and green fuels as a possible replacement for ammonium perchlorate(NH4ClO4,AP) and hydrazine(N2H4) respectively has been increased considerably in the recent years.AP and hy...Research and development of green oxidizers and green fuels as a possible replacement for ammonium perchlorate(NH4ClO4,AP) and hydrazine(N2H4) respectively has been increased considerably in the recent years.AP and hydrazine are the oxidizer and fuel entities,and used in solid and liquid rocket motors respectively.AP is highly toxic and led to adverse health effects,while hydrazine is carcinogenic in nature.AP is in use from the last several decades for rocket and space shuttle propulsion,while hydrazine is used in upper stage liquid propelled rocket motors.It’s a tough task to replace AP with the currently available green oxidizers;since their ballistic properties are weaker when compared to AP and also they can’t be successfully deployed in a solid rocket motor at present Some important available solid green oxidizers are ammonium nitrate(AN),ammonium dinitramide(ADN),hydroxyl ammonium nitrate(HAN),and hydrazinium nitroformate(HNF).However,AN is one of the cheap and readily available oxidizer,and has great potential to use in solid/liquid rocket motors.Tremendous progress has been envisaged till now,and more progress will be there in the coming future over the development of AN based green energetic materials(GEM’s).A concise overview has been presented over the development of phase stabilized ammonium nitrate(PSAN) and AN/KDN based green oxidizers in the present review paper.展开更多
The effects of dissolved organic matter （DOM） on the removal of nitrate-nitrogen from the model contaminated water have been investigated utilizing the strong base anion exchange resins. With the increase of gallic ...The effects of dissolved organic matter （DOM） on the removal of nitrate-nitrogen from the model contaminated water have been investigated utilizing the strong base anion exchange resins. With the increase of gallic acid concentration from 0 to 400 mg/L, the adsorption amount of nitrate-nitrogen on the commercial resins, including D201, Purolite A 300 （A300） and Purolite A 520E （A520E）, would significantly decrease. However, the presence of tannin acid has little impact on nitrate-nitrogen adsorption on them. Compared to D201 and A300 resins, A520E resin exhibited more preferable adsorption ability toward nitrate-nitrogen in the presence of competing organic molecules, such as gallic acid and tannin acid at greater levels in aqueous solution. Attractively, the equilibrium data showed that the adsorption isotherm of nitrate-nitrogen on A520E resin was in good agreement with Langmuir and Fretmdlich equations. The rate parameters for the intra particle diffusion have been estimated for the different initial concentrations. In batch adsorption processes, nitrate-nitrogen diffuse in porous adsorbent and rate process usually depends on t1/2 rather than the contact time. The pseudo first- and the second-order kinetic models fit better for nitrate-nitrogen adsorption onto A520E resin. The observations reported herein illustrated that A520E resin will be an excellent adsorbent for enhanced removal of nitrate-nitrogen from contaminated groundwater.展开更多
Excess or lack of levels of nitrate in drinking water is harmful to the human health, the concentration of NO-3 ions must be maintained at 50 mg/l. Donnan dialysis (DD) used as a driving force of the concentration gra...Excess or lack of levels of nitrate in drinking water is harmful to the human health, the concentration of NO-3 ions must be maintained at 50 mg/l. Donnan dialysis (DD) used as a driving force of the concentration gradient is an effective and simple technique for nitrate removal. In this paper, the transport of nitrate through an AMX anion-exchange membrane has been studied as a function of driving ion nature, receiver phase concentration, flow rate, temperature and agitation rate under Donnan dialysis condition. It was observed that the hydrodynamic conditions and temperature were the main variables affecting the transmembrane flow. As the driving ion, the chloride ion is more efficient than the hydrogeneocarbonate ion. The systematic study of the different parameters involved showed that the nitrate removal efficiency obtained with a feed synthetic nitrate solution (62 ppm) was off 96%. This efficiency slightly decreases for a tap water containing the same nitrate concentration;it was about 84%. This can be attributed to the complex ionic composition of the natural water.展开更多
基金provided by Program for Changjiang Scholars and Innovative Research Team in University,NSFC(Nos.50825802 and 51178215)Jiangsu Natural Science Fund(Nos. BK2010006 and BK2011032),China
文摘A novel magnetic anion exchange resin NDM-1 was prepared through suspension polymerization and then functionalized with ammonolysis and alkylating agents.Its application for selective removal of nitrate was performed in comparison with MIEX.The results demonstrated that NDM-1 achieved higher efficiency in nitrate removal than MIEX did,with or without the existence of competing anion SO_4^2- ascribed to its longer alkyl chains on exchange sites.Combined with the advantage of easy separation due toγ-Fe_2O_3 implanted,the magnetic anion exchange resin NDM-1 was considered to be superior to MIEX for nitrate removal in practical application.
文摘Sorption recovery of palladium (II) from nitrate weak acidic model solutions and solutions of spent catalysts on some ion exchangers with different physical and chemical structure has been investigated. The palladium concentration in contacting solutions was 5.0 ? 10-5 – 1.0 ? 10-3 mol/L at nitric acid and potassium nitrate con-centrations 0.01 and 1.0 mol/L, respectively. It was shown that anion exchangers AV-17-8 as well as Purolite S 985 and A 500 possess the best sorption and kinetic properties. These sorbents can be recommended for selective recovery of palladium from solutions of spent catalysts.
基金acknowledge generous suppoa provided by Program for Changjiang Scholars Innovative Research Team in UniversityNSFC(Nos50938004,50825802 and 51178215)+1 种基金Jiangsu Natural Science Fund(Nos BK2010006 and BK201 1032)P.R. Chinathe Scientific Research Starting Fund for Postdoctors,Nanjing University(No0211003046)
文摘An anion exchange resin NDP-5 has been prepared successfully and applied on the selective removal of nitrate from SO_4^（2-）/ NO_3^- binary co-existence system.The composition and morphology of NDP-5 were confirmed by FT-IR and SEM.The NDP-5 resin exhibits the completely different behavior on the adsorption capacity,adsorption kinetic and the effect of the completing anion in the absence or presence of sulfate,compared to D213.And,the resultants of kinetic are well fitted by the pseudo-first-order and pseudo-second-order models.These results are very important to develop novel resins with great features.
基金supported by the Department of Science and Technology of Fujian Province,China,under theproject No. 2002H009
文摘An improved method,suitable for collecting nitrate from surface waters in the watershed for 15 N isotope tracing analysis,was developed on the basis of the anion exchange coupled with diffusion through systematic simulation and comparison experiments.The results showed that the nitrate could be separated and enriched from the waters efficiently by using the improved method.Being simple and practical in operation principle and procedures,cost-economic,and highly efficient in nitrate separation/enrichment,the method met the requirements of δ 15 N mass spectrum analysis and would lay a foundation for the application of 15 N isotope tracing approach to the research on non-point source pollution in watershed.
文摘选择新型强碱性阴离子交换树脂Amberlite IRA 402和Amberlite IRA 900,与201×7(717)树脂对比,进行吸附去除水中硝氮的实验研究。通过拟合3种树脂的控速步骤和动力学模型,研究吸附过程的动力学行为,并考虑了不同初始浓度的硝酸盐溶液、温度、溶解性有机质(DOM)、pH和转速等的影响。结果表明,IRA 402树脂对硝氮的吸附效果最好(吸附率99.3%),717次之(吸附率98.2%),IRA900稍弱(吸附率93%),但相差不大,且IRA402比较适合去除高浓度DOM废水的硝氮,没食子酸对硝氮去除的影响高于单宁酸。3种树脂吸附硝氮的过程主要受化学反应控制,并符合准二级动力学方程。温度的变化对3种树脂吸附硝氮的行为影响不是很大,可以选择在室温下(25℃)进行。在pH 7.0时,3种树脂吸附硝氮的效果最好,树脂吸附硝氮的转速可设置为200 r/min。
文摘Research and development of green oxidizers and green fuels as a possible replacement for ammonium perchlorate(NH4ClO4,AP) and hydrazine(N2H4) respectively has been increased considerably in the recent years.AP and hydrazine are the oxidizer and fuel entities,and used in solid and liquid rocket motors respectively.AP is highly toxic and led to adverse health effects,while hydrazine is carcinogenic in nature.AP is in use from the last several decades for rocket and space shuttle propulsion,while hydrazine is used in upper stage liquid propelled rocket motors.It’s a tough task to replace AP with the currently available green oxidizers;since their ballistic properties are weaker when compared to AP and also they can’t be successfully deployed in a solid rocket motor at present Some important available solid green oxidizers are ammonium nitrate(AN),ammonium dinitramide(ADN),hydroxyl ammonium nitrate(HAN),and hydrazinium nitroformate(HNF).However,AN is one of the cheap and readily available oxidizer,and has great potential to use in solid/liquid rocket motors.Tremendous progress has been envisaged till now,and more progress will be there in the coming future over the development of AN based green energetic materials(GEM’s).A concise overview has been presented over the development of phase stabilized ammonium nitrate(PSAN) and AN/KDN based green oxidizers in the present review paper.
基金supported by the Program for Changjiang Scholars Innovative Research Team in University and NS-FC (No.50938004,51178215,51008152)the Jiangsu Nature Science Foundation for Distinguished Scientists(No.BK2010006, BK2011032)the Scientific Research Starting Found for Postdoctors,Nanjing University(No.0211003046, 021114340069)
文摘The effects of dissolved organic matter （DOM） on the removal of nitrate-nitrogen from the model contaminated water have been investigated utilizing the strong base anion exchange resins. With the increase of gallic acid concentration from 0 to 400 mg/L, the adsorption amount of nitrate-nitrogen on the commercial resins, including D201, Purolite A 300 （A300） and Purolite A 520E （A520E）, would significantly decrease. However, the presence of tannin acid has little impact on nitrate-nitrogen adsorption on them. Compared to D201 and A300 resins, A520E resin exhibited more preferable adsorption ability toward nitrate-nitrogen in the presence of competing organic molecules, such as gallic acid and tannin acid at greater levels in aqueous solution. Attractively, the equilibrium data showed that the adsorption isotherm of nitrate-nitrogen on A520E resin was in good agreement with Langmuir and Fretmdlich equations. The rate parameters for the intra particle diffusion have been estimated for the different initial concentrations. In batch adsorption processes, nitrate-nitrogen diffuse in porous adsorbent and rate process usually depends on t1/2 rather than the contact time. The pseudo first- and the second-order kinetic models fit better for nitrate-nitrogen adsorption onto A520E resin. The observations reported herein illustrated that A520E resin will be an excellent adsorbent for enhanced removal of nitrate-nitrogen from contaminated groundwater.
文摘Excess or lack of levels of nitrate in drinking water is harmful to the human health, the concentration of NO-3 ions must be maintained at 50 mg/l. Donnan dialysis (DD) used as a driving force of the concentration gradient is an effective and simple technique for nitrate removal. In this paper, the transport of nitrate through an AMX anion-exchange membrane has been studied as a function of driving ion nature, receiver phase concentration, flow rate, temperature and agitation rate under Donnan dialysis condition. It was observed that the hydrodynamic conditions and temperature were the main variables affecting the transmembrane flow. As the driving ion, the chloride ion is more efficient than the hydrogeneocarbonate ion. The systematic study of the different parameters involved showed that the nitrate removal efficiency obtained with a feed synthetic nitrate solution (62 ppm) was off 96%. This efficiency slightly decreases for a tap water containing the same nitrate concentration;it was about 84%. This can be attributed to the complex ionic composition of the natural water.
