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Adsorption behavior and mechanism of cadmium on strong-acid cation exchange resin 被引量:6
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作者 王菲 王连军 +2 位作者 李健生 孙秀云 韩卫清 《中国有色金属学会会刊:英文版》 CSCD 2009年第3期740-744,共5页
The adsorption behavior of Cd2+ on 001×7 strong-acid cation exchange resin was studied with the static adsorption method. The adsorption process was analyzed from thermodynamics and kinetics aspects. The influenc... The adsorption behavior of Cd2+ on 001×7 strong-acid cation exchange resin was studied with the static adsorption method. The adsorption process was analyzed from thermodynamics and kinetics aspects. The influences of experimental parameters such as pH, temperature, initial concentration and adsorption rate were investigated. The experimental results show that in the studied concentration range, 001×7 resin has a good sorption ability for Cd2+, and the equilibrium adsorption data fit to Freundlich isotherms. The adsorption is an exothermic process which runs spontaneously. Kinetic analysis shows that the adsorption rate is mainly governed by liquid film diffusion. The best adsorption condition is pH 4-5. The saturated resin can be regenerated by 3 mol/L nitric acid, and the desorption efficiency is over 98%. The maximal static saturated adsorption capacity is 355 mg/g (wet resin) at 293 K. The adsorption mechanism of Cd2+ on 001×7 resin was discussed based on IR spectra. 展开更多
关键词 强酸性阳离子交换树脂 吸附行为 饱和吸附容量 动力学分析 机理 实验参数 吸附方法
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Mechanism and kinetics study on removal of Iron from phosphoric acid by cation exchange resin 被引量:7
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作者 Xinke Leng Yanjun Zhong +2 位作者 Dehua Xu Xinlong Wang Lin Yang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第5期1050-1057,共8页
Iron element is one of the main impurities in wet-process phosphoric acid and it has a significant impact on the subsequent phosphorus chemical products. This paper studied the feasibility of using Sinco-430 cation ex... Iron element is one of the main impurities in wet-process phosphoric acid and it has a significant impact on the subsequent phosphorus chemical products. This paper studied the feasibility of using Sinco-430 cation exchange resin for iron removal from phosphoric acid. The specific surface area and the total exchange capacity of resin were 8.91 m2·g-1 and 5.18 mmol·g-1, respectively. The sorption mechanism was determined by FTIR and XPS and the results indicated that iron was combined with-SO3 H in resin. The removal process was studied as a function of temperature, H3 PO4 content and mass ratio between resin and solution. The unit mass of resin to remove iron was 0.058 g·g-1 resin when the operating parameters were T = 50 ℃, H3 PO4 content = 27.61 wt%and S/L = 0.1, respectively. Kinetics study demonstrated that pseudo-second-order reaction model fits this study best and the calculated activation energy of overall reaction is 29.10 kJ·mol-1. The overall reaction process was mainly controlled by pore diffusion. 展开更多
关键词 PURIFIcation of wet-process phosphoric acid cation exchange resin KINETICS MODELS DIFFUSION MODELS
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Separation of Clay Minerals from Host Sediments Using Cation Exchange Resins 被引量:2
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作者 I.S.Ismael H.M.Baioumy 《Chinese Journal Of Geochemistry》 EI CAS 2003年第4期337-344,共8页
Classic physical and chemical treatments applied to separating clay minerals from the host sediments are often difficult or aggressive for clay minerals. A technique using cation exchange resins (amberlite IRC\|50H an... Classic physical and chemical treatments applied to separating clay minerals from the host sediments are often difficult or aggressive for clay minerals. A technique using cation exchange resins (amberlite IRC\|50H and amberlite IR\|120) is used to separate clay minerals from the host sediments. The technique is based on the exchange of cations in the minerals that may be associated clay minerals in sediments, such as Ca and Mg from dolomite; Ca from calcite, gypsum and francolite with cations carried by resin radicals. The associated minerals such as gypsum, calcite, dolomite and francolite are removed in descending order. Separation of clay minerals using cation exchange resins is less aggressive than that by other classic treatments. The efficiency of amberlite IRC\|50H in the removal of associated minerals is greater than that of amberlite IR\|120. 展开更多
关键词 CLAY MINERAL HOST sediment cation exchange resin Experimental technique separate
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Synthesis of cation exchange resin-supported iron and magnesium oxides/hydroxides composite for nitrate removal in water 被引量:2
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作者 Trung Thanh Nguyen Vu Anh Khoa Tran +6 位作者 Le Ba Tran Phuoc Toan Phan Minh Tan Nguyen Long Giang Bach Surapol Padungthon Cong Khiem Ta Nhat Huy Nguyen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第4期378-384,共7页
In this study,we reported on the concept and practical use of cation exchange resin(CER)for removing anions in water via pretreating the CER with metal salts.The cation exchange resinsupported iron and magnesium oxide... In this study,we reported on the concept and practical use of cation exchange resin(CER)for removing anions in water via pretreating the CER with metal salts.The cation exchange resinsupported iron and magnesium oxides/hydroxides composite(FeMg/CER)was synthesized and introduced as a new and potential adsorbent for selective removal of nitrate ion in the water environment.Characteristics of FeMg/CER were determined by techniques such as Fouriertransform infrared spectroscopy,scanning electron microscopy,and Xray diffraction.The results showed that FeMg/CER material had a high nitrate adsorption capacity of 200 mg NO_(3)^()·g^(1)with a fast equilibrium adsorption time of 30 min at pH 5.In addition,it had good durability of at least 10 times of regeneration,which could be applied to practical water and wastewater treatment. 展开更多
关键词 Iron oxide/hydroxide Magnesium oxide/hydroxide cation exchange resin ADSORPTION Environment NANOMATERIALS
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Kinetic and thermodynamic studies of the esterification of acidified oil catalyzed by sulfonated cation exchange resin 被引量:8
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作者 Lingling Ma Ying Han +2 位作者 Kaian Sun Jie Lu Jincheng Ding 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2015年第4期456-462,共7页
This study describes the kinetics and thermodynamics of the esterification of acidified oil with methanol catalyzed by sulfonated cation exchange resins(SCER). The effects of the mass ratio of methanol to acidified oi... This study describes the kinetics and thermodynamics of the esterification of acidified oil with methanol catalyzed by sulfonated cation exchange resins(SCER). The effects of the mass ratio of methanol to acidified oil,reaction temperature,and catalyst loading were studied to optimize the conditions for maximum conversion of free fatty acids(FFAs). The results showed that the optimal conversion rate of FFAs was 91.87% at the mass ratio of methanol to acidified oil of 2.5:1.0,reaction temperature of 65.0 °C,catalyst loading of 5.0 g and reaction time of 8.0 h. The external and internal mass transfer resistances were negligible based on the experimental results and a pseudo-homogeneous kinetic model was proposed for the esterification. The activation energy and thermodynamic parameters including G,S and H were determined. The conversion rates of FFAs obtained from the established model were in good agreement with the experimental data. 展开更多
关键词 阳离子交换树脂 催化酯化反应 动力学模型 热力学参数 酸化油 游离脂肪酸 磺化 反应温度
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Elements, Structure and Electrochemical Property of Carbon Derived from La^(3+) Adulterating Polystyrene Cation Exchange Resin
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作者 WANG Shu jun 1, LIU Qing guo 2 ( 1. Department of Chemical Engineer, University of Petroleum Beijing, Beijing 102200, China 2. Department of Physical Chemistry, University of Science and Technology Beijing, Beijing 100083, China) 《Journal of Rare Earths》 SCIE EI CAS CSCD 2000年第3期214-214,共1页
The polystyrene cation exchange resin was exchanged by La 3+ and then were carbonized to make resin carbon material. The electrochemical properties of the resin carbon material as the electrode of the lithium ion cell... The polystyrene cation exchange resin was exchanged by La 3+ and then were carbonized to make resin carbon material. The electrochemical properties of the resin carbon material as the electrode of the lithium ion cell were investigated. The test results show that comparing with the polystyrene cation exchange resin without adulterating, the contents of hydrogen, oxygen and sulfur are changed obviously for the resin carbon material derived from the La 3+ adulterating polystyrene cation exchange resin. The contents of hydrogen and oxygen are increased, and the one of sulfur is decreased. The test results also indicate that it is more easily to form the stratum graphite minicrystal structure with bigger diameter for the La 3+ adulterating resin. According to the electrochemical test results, the electrode derived from La 3+ adulterating polystyrene cation exchange resin has much better electrochemical property, and the capacity of charge and discharge of the electrode is increased about 30 mAh·g -1 in average. 展开更多
关键词 RARE earths ion adulterating POLYSTYRENE cation exchange resin CARBON ELECTRODE material
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Elution Behaviour of Monocarboxylic Acids on a Cation-exchange Resin Column
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作者 Zhao Guoliang and Liu Zhiguang (Department of Chemistry, Mian University of Technology, Dalian) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1989年第3期237-243,共7页
The retention mechanism of monocarboxylic acids on a cation-exchange resin column was investigated. It was assumed that both Donnan membrane equilibrium and adsorption equilibrium were involved in the chromatographic ... The retention mechanism of monocarboxylic acids on a cation-exchange resin column was investigated. It was assumed that both Donnan membrane equilibrium and adsorption equilibrium were involved in the chromatographic process. On the basis of the proposed mechanism, an equation was derived for correlating distribution coefficient, Kd, dissociation constant, Aa, and adsorption equilibrium constant, K, of the analyzed acid. By this approach, retention data for some aliphatic acids under different operating conditions were predicted. Results are reasonably in agreement with experiment. 展开更多
关键词 Ion EXCLUSION CHROMATOGRAPHY Monocarboxylic ACIDS cation-exchange resin
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FACTORS AFFECT THE RELEASE OF PSEUDOEPHDRINE HYDROCHLORIDE FROM THE UNCOATED CATION EXCHANGE RESIN-BASED DRUG DELIVERY SYSTEM IN VITRO
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作者 LIZhenhua PIHongqiong 《Chinese Journal of Reactive Polymers》 2001年第1期8-14,共7页
In this paper, it was investigated that the effect of parameters such as the ionic strength, pH, counter-ion type of release medium, particle size, and cross linkage of cation exchange resin on the release of model dr... In this paper, it was investigated that the effect of parameters such as the ionic strength, pH, counter-ion type of release medium, particle size, and cross linkage of cation exchange resin on the release of model drug pseudoephedrine hydrochloride (PE) from uncoated drug-resin complex. The drug-resin complex was prepared by the reaction of PE with strongly acidic cation exchange resin (001×4, 001×7, 001×14). The result showed that the loading of PE increased with the increase of temperatures. The release of PE from drug-resin complex at 37℃ was monitored in vitro. From the experiments, it was found that the release rate of PE depends on the pH, composition of the releasing media, increased at lower pH media or with increase of ionic strength of media. Moreover, the release rate of PE was inversely proportional to the cross-linkage and particle size of the cation exchange resin. 展开更多
关键词 阳离子交换树脂 假麻黄碱 药输送系统
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Decomposition mechanisms of nuclear-grade cationic exchange resin by advanced oxidation processes:Statistical molecular fragmentation model and DFT calculations
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作者 Xiang Meng Pierre Désesquelles Lejin Xu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第1期433-448,共16页
The treatment and disposal of radioactive waste are presently facing great challenges.Spent ion exchange resins have become a focus of attention due to their high production and serious environmental risks.In this pap... The treatment and disposal of radioactive waste are presently facing great challenges.Spent ion exchange resins have become a focus of attention due to their high production and serious environmental risks.In this paper,a simplified model of cationic exchange resin is proposed,and the degradation processes of cationic resin monomer initiated by hydroxyl radicals(·OH)are clarified by combining statistical molecular fragmentation(SMF)model and density functional theory(DFT)calculations.The prediction of active sites indicates that the S-O bonds and the C-S bond of the sulfonic group are more likely to react during the degradation.The meta-position of the sulfonic group on the benzene ring is the most active site,and the benzene ring without the sulfonic group has a certain reactivity.The C11-C14 and C17-C20 bonds,on the carbon skeleton,are the most easily broken.It is also found that dihydroxy addition and elimination reactions play a major role in the process of desulfonation,carbon skeleton cleavage and benzene ring separation.The decomposition mechanisms found through the combination of physical models and chemical calculations,provide theoretical guidance for the treatment of complex polycyclic aromatic hydrocarbons. 展开更多
关键词 cationic exchange resin Statistical molecular fragmentation model Density functional theory Hydroxyl radical Decomposition mechanism
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磺酸型阳离子树脂的元素分配行为及高精度同位素分析应用
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作者 王奇奇 孙贺 +4 位作者 顾海欧 侯振辉 葛粲 汪方跃 周涛发 《岩矿测试》 CAS CSCD 北大核心 2024年第1期63-75,共13页
不同元素在离子交换树脂的分配系数是元素纯化和分离的基础,不同酸中各元素分配系数差异可用于设计高效的元素提纯流程,从而被广泛应用于现代高精度同位素分析。本文以AG®50W-X8阳离子树脂为研究对象,以分配系数(Kd)作为量化指标,... 不同元素在离子交换树脂的分配系数是元素纯化和分离的基础,不同酸中各元素分配系数差异可用于设计高效的元素提纯流程,从而被广泛应用于现代高精度同位素分析。本文以AG®50W-X8阳离子树脂为研究对象,以分配系数(Kd)作为量化指标,通过系统实验研究不同元素在该树脂中的分配行为。在前人研究基础上,本实验增加了元素数量和酸的种类,涵盖了金属、类金属、非金属和稀土元素。结果表明:在盐酸和硝酸介质中,几乎所有元素的Kd都与酸度呈负相关,当酸度达到6mol/L时,除Th和Ca以外的所有元素都会被酸洗脱。稀土元素(REEs)和高场强元素在0.1~0.5mol/L稀硝酸和稀盐酸中强烈吸附在树脂上;而一些过渡金属、类金属和非金属元素(如Mo、W、Re、Ir、Sb、Ge、As、Se、Te等)在酸溶液中会形成含氧阴离子,不与阳离子树脂发生吸附。Al、Fe、Se、Pd、Cd、In等元素在盐酸中易与氯离子形成配位化合物或离子团,导致这些离子在盐酸中的分配系数显著降低。在硝酸和盐酸与氢氟酸的混合酸中,除稀土元素外,绝大部分元素随酸度增加Kd迅速降低。稀土元素在盐酸-氢氟酸混合介质中,随着盐酸的浓度增加(从0.1mol/L盐酸-0.2mol/L氢氟酸至6mol/L盐酸-0.2mol/L氢氟酸),稀土元素分配系数(KdREE)具有先增加后降低的趋势。氢氟酸的加入可显著降低Be、Al、Sc、Fe、Sn、Th、U、Ti、Zr、Hf等元素在稀盐酸和稀硝酸中的分配系数,使这些元素几乎不与树脂发生吸附。本研究揭示了不同酸介质中各类元素在阳离子交换树脂上的分配行为存在差异,尤其是氢氟酸的加入可显著改变高场强元素、部分过渡金属和稀土元素的分配系数,为应用该树脂开发和优化适用于高精度金属稳定同位素分析的元素提纯流程(如Li、Mg、K、Sr、Ce、U等)提供了数据支撑,并可有效地减少后续实验设计的工作量。 展开更多
关键词 BioRad AG®50W-X8阳离子树脂 元素提纯 高精度同位素分析 分配系数 离子交换柱
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乙二胺改性聚苯乙烯树脂对水体中铅(Ⅱ)、铬(Ⅵ)的吸附研究
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作者 史舒焕 董岁明 《化工新型材料》 CAS CSCD 北大核心 2024年第2期201-205,共5页
采用乙二胺对氯甲基化聚苯乙烯树脂进行改性,利用改性后的树脂去除溶液中的铅(Ⅱ)和铬(Ⅵ)。通过改变pH、时间、浓度和吸附剂投加量,确定最佳吸附实验条件,得到改性后的树脂对铅(Ⅱ)和铬(Ⅵ)的最大吸附容量分别为119.60mg/g和128.28mg/... 采用乙二胺对氯甲基化聚苯乙烯树脂进行改性,利用改性后的树脂去除溶液中的铅(Ⅱ)和铬(Ⅵ)。通过改变pH、时间、浓度和吸附剂投加量,确定最佳吸附实验条件,得到改性后的树脂对铅(Ⅱ)和铬(Ⅵ)的最大吸附容量分别为119.60mg/g和128.28mg/g。动力学研究表明,该模型符合Langmuir模型。 展开更多
关键词 阳离子树脂 重金属离子
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Evaluation of D113 cation exchange resin for the removal of Eu(Ⅲ) from aqueous solution 被引量:6
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作者 熊春华 郑展望 《Journal of Rare Earths》 SCIE EI CAS CSCD 2010年第6期862-867,共6页
Batch adsorption experiments were conducted for the adsorption of Eu(Ⅲ) ions from aqueous solution by D113 resin. The results indicated that D113 resin could adsorb Eu(Ⅲ) ion effectively from aqueous solution. The a... Batch adsorption experiments were conducted for the adsorption of Eu(Ⅲ) ions from aqueous solution by D113 resin. The results indicated that D113 resin could adsorb Eu(Ⅲ) ion effectively from aqueous solution. The adsorption was strongly dependent on pH of the medium with enhanced adsorption as the pH turned from 3.50 to 7.00 and the optimal adsorption condition was in HAc-NaAc medium with pH value of 6.50. The maximum uptake capacity of Eu(Ⅲ) ions was 290.9 mg/g D113 at 298 K, at an initial pH value of 6.50. The overall adsorption process was best described by Lagergren-first-order kinetics. When Freundlich and Langmuir isotherms were tested, the latter had a better fit with the experimental data. The thermodynamic parameters such as free energy (G) which were all negative, indicated that the adsorption of Eu(Ⅲ) ions onto D113 resin was spontaneous and the positive value of enthalpy (H) showed that the adsorption was endothermic in nature. Thomas model was applied to experimental column data to determine the characteristic parameters of column useful for process design. Furthermore, Eu(Ⅲ) could be eluted by using 3.0 mol/L HCl solution and the D113 resin could be regenerated and reused. 展开更多
关键词 cation exchange resin EVALUATION aqueous solution thermodynamic parameters pH value UPTAKE capacity ions free energy FREUNDLICH positive negative LANGMUIR data results initial better model HCI
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Cation exchange resin supported nanoscale zero-valent iron for removal of phosphorus in rainwater runoff 被引量:2
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作者 Bangmi XIE Jiane ZUO Lili GAN Fenglin LIU Kaijun WANG 《Frontiers of Environmental Science & Engineering》 SCIE EI CAS CSCD 2014年第3期463-470,共8页
白手起家的阳离子交换树脂支持的 nanoscale zero-valent 铁(R-nZVI ) 被用来在雨水流量移开磷。在从草地的雨水流量的 80% 磷与 0.72 mg
关键词 阳离子交换树脂 雨水径流 零价铁 纳米级 除磷 比表面积分析 电感耦合等离子体 X射线光电子能谱
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Preparation and characterization of EVAL hollow fiber membrane adsorbents filled with cation exchange resins
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作者 Fengli ZHANG Yuzhong ZHANG +1 位作者 Guangfen LI Hong LI 《Frontiers of Chemical Science and Engineering》 SCIE EI CSCD 2009年第4期462-467,共6页
EVAL hollow fiber membrane adsorbents filled with powder D061-type cation exchange resin were prepared through dry-wet spinning process,using hydrophilic copolymer EVAL as the fiber substrate.The microstructures of th... EVAL hollow fiber membrane adsorbents filled with powder D061-type cation exchange resin were prepared through dry-wet spinning process,using hydrophilic copolymer EVAL as the fiber substrate.The microstructures of the membrane adsorbents were observed,and the pure water fluxes,BSA rejection,and static adsorption capacities of membrane adsorbents for BSA were measured.The effect of the resin-filled content on membrane performance has been discussed.The results showed that EVAL hollow fiber membrane adsorbents filled with D061-type cation exchange resins had good adsorption capacity,and the adsorption capacity increased with the quantity of the resin-filled content.The static protein adsorption capacity was 77.14 mg BSA/g membrane adsorbents when D061 resin loading content was 65%at pH 4.5. 展开更多
关键词 EVAL hollow fiber membrane adsorbents cation exchange resin adsorption capacity
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Catalytic effects of V_(2)O_(5) on oxidative pyrolysis of spent cation exchange resin
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作者 Qi SONG Jian-hua SHEN +3 位作者 Yong YANG Yao YANG Bin-bo JIANG Zu-wei LIAO 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2021年第2期94-105,共12页
Pyrolysis is a cost-effective and safe method for the disposal of radioactive spent resins.In this work,the catalytic effects of V_(2)O_(5) on the pyrolysis of cation exchange resin are investigated for the first time... Pyrolysis is a cost-effective and safe method for the disposal of radioactive spent resins.In this work,the catalytic effects of V_(2)O_(5) on the pyrolysis of cation exchange resin are investigated for the first time.The results show that it is a better catalyst than others so far studied and achieves a lowering of final pyrolysis temperature and residual rate simultaneously when aided by physical blending.The maximum reductions of the final pyrolysis temperature and the residual rate are 173℃and 11.9%(in weight),respectively.Under the action of V_(2)O_(5),low-temperature(445℃)removal of partial sulfonic acid groups occurs and the pyrolysis of the resin copolymer matrix is promoted.This is demonstrated by the analysis of pyrolysis residues at different temperatures by X-ray photoelectron spectroscopy(XPS)and element analysis.The catalytic activity of V_(2)O_(5) is determined by effects both at acid sites and oxidation-reduction centers via H2-TPR(temperature programmed reduction),V_(2)-TPD(temperature programmed desorption),CV_(2)-TPD,and NH3-TPD.The catalytic effect of oxidation-reduction centers in V_(2)O_(5) is achieved by close contact with the sulfur bond through chemisorption under the effect of acid sites.V_(2)O_(5) is also believed to be the reason for the removal of partial sulfonic acid groups at lower temperatures(445℃).V_(2)O_(5) is an effective catalyst for spent resin pyrolysis and can be further applied in industry. 展开更多
关键词 Waste disposal cation exchange resin V2O5 CATALYSIS Oxidative pyrolysis
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ISOLATION AND PURIFICATION OF ALKALOIDS FROM PLUMULA NELUMBINIS BY DOUBLE-COLUMN ADSORPTION CHROMOTOGRAPHY
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作者 ZHANG Jixiang GUO Jinsheng OU Lailiang 《Chinese Journal of Reactive Polymers》 2007年第1期119-124,共6页
The performance of adsorption and separation for liensinine, isoliensinine and neferine was studied by double-column adsorption chromatography using macroporous adsorption and cation exchange resins. The alkaloid extr... The performance of adsorption and separation for liensinine, isoliensinine and neferine was studied by double-column adsorption chromatography using macroporous adsorption and cation exchange resins. The alkaloid extract with 49.2% total contents by mass representing 10.6% liensinine, 10.6% isoliensinine and 28.0% neferine respectively was prepared by D72 cation exchange resins, in which most of the impurities were water-soluble alkaloids. Furthermore,the alkaloid extract with 82.6% total contents by mass containing 33.1%, 15.0% and 34.5% of the three adsorbates respectively was prepared by double-column adsorption chromatography using AKS-W macroporous adsorption and D72 cation exchange resins. As a result, the content of single and total alkaloids has been greatly increased by the double-column adsorption chromatography. 展开更多
关键词 离子交换剂 吸附作用 光谱法 大孔吸附
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阳离子交换树脂催化合成乳酸甲酯动力学研究
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作者 刘辉 刘鑫 +3 位作者 项文雨 郭凯 刘春江 张青军 《天津大学学报(自然科学与工程技术版)》 EI CAS CSCD 北大核心 2023年第12期1227-1234,共8页
工业化生产乳酸甲酯需要特定催化剂的动力学数据进行模拟计算.本文研究了在大孔阳离子交换树脂DA330的催化作用下,乳酸和甲醇生成乳酸甲酯的反应动力学.乳酸甲酯是一种重要的化工生产基础原料,多用来作为合成香料和农药的原料.随着化石... 工业化生产乳酸甲酯需要特定催化剂的动力学数据进行模拟计算.本文研究了在大孔阳离子交换树脂DA330的催化作用下,乳酸和甲醇生成乳酸甲酯的反应动力学.乳酸甲酯是一种重要的化工生产基础原料,多用来作为合成香料和农药的原料.随着化石能源紧缺和环保要求提高,具有可降解和可再生特性的乳酸甲酯及其高聚物的需求也在与日俱增.乳酸甲酯的连续化生产是提高乳酸甲酯产量的关键,具有广阔的研究前景.采用固体大孔阳离子交换树脂代替传统浓硫酸作为催化剂,需要对动力学方程进行重新测定.本文针对乳酸甲酯反应体系外扩散影响、内扩散影响、酯化反应动力学、水解反应动力学分别进行了实验.采用气相色谱对反应体系中的乳酸甲酯含量进行测定.研究发现内、外扩散在实验条件范围内对反应速率无明显影响:以酯化反应为例,搅拌转速达400 r/min以上时体系内催化剂颗粒悬浮程度达到峰值,外扩散不影响酯化反应速率;在催化剂颗粒悬浮程度达到峰值之后,催化剂粒径大小不影响酯化反应速率.反应温度在实验范围内对反应速率呈现显著的正相关影响,酯化和水解实验数据拟合均符合Quasi-Homogeneous模型,最终得到DA330催化条件下的反应动力学. 展开更多
关键词 乳酸甲酯 阳离子交换树脂 固体催化剂 动力学研究
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阳离子树脂基铁锰铈吸附剂的制备及其去除水中铅、铬的性能研究
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作者 张洛红 刘建宇 +2 位作者 刘彩琴 杨巧巧 李庆 《功能材料》 CAS CSCD 北大核心 2023年第5期5133-5140,共8页
为了获得去除重金属离子Pb^(2+)和Cr^(6+)的特异性强、易回收的高性能吸附剂,通过将铁锰铈金属氧化物(Fe-Mn-Ce)负载到强酸性阳离子树脂(D001)上,成功制备了树脂基铁锰铈吸附剂(Fe-Mn-Ce@D001)。研究了吸附剂对水中Pb^(2+)、Cr^(6+)的... 为了获得去除重金属离子Pb^(2+)和Cr^(6+)的特异性强、易回收的高性能吸附剂,通过将铁锰铈金属氧化物(Fe-Mn-Ce)负载到强酸性阳离子树脂(D001)上,成功制备了树脂基铁锰铈吸附剂(Fe-Mn-Ce@D001)。研究了吸附剂对水中Pb^(2+)、Cr^(6+)的去除性能,考察了不同因素对Pb^(2+)、Cr^(6+)去除率的影响,同时进行吸附动力学以及吸附热力学实验,探讨其吸附规律。实验结果表明:在温度为298K、pH=5、投加量为0.01g时,Fe-Mn-Ce@D001对Pb^(2+)和Cr^(6+)的饱和吸附容量分别为528.06mg/g和218.33mg/g,优于原树脂D001。Fe-Mn-Ce@D001树脂比D001对Pb^(2+)和Cr^(6+)具有更高的吸附选择性,在高浓度Ca^(2+)、Mg^(2+)、NO_(3)^(-)、SO_(4)^(2-)等离子共存的条件下仍保持较高的去除率;在Pb^(2+)和Cr^(6+)混合溶液中比D001具有更好的同步吸附性能;相对于D001具备更好地重复利用性。Fe-Mn-Ce@D001对Pb^(2+)和Cr^(6+)的吸附等温模型均符合Langmuir模型,吸附动力学行为与准一级动力学和准二级动力学均能很好的相符。 展开更多
关键词 吸附 阳离子交换树脂 铁锰铈金属氧化物 去除
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阳离子交换树脂分离-电感耦合等离子体发射光谱(ICP-OES)法测定盐湖卤水中偏硅酸含量 被引量:3
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作者 王洋 张露露 +2 位作者 王木荣 徐红印 张延芳 《中国无机分析化学》 CAS 北大核心 2023年第8期857-862,共6页
由于盐湖卤水中盐分浓度不同且盐度较高,采用常规分析方法很难准确测定。通过对阳离子交换树脂加入量、阳离子交换树脂交换时间、pH值对交换效率的影响、内标元素校正的考察,建立了阳离子交换树脂分离-电感耦合等离子体发射光谱法测定... 由于盐湖卤水中盐分浓度不同且盐度较高,采用常规分析方法很难准确测定。通过对阳离子交换树脂加入量、阳离子交换树脂交换时间、pH值对交换效率的影响、内标元素校正的考察,建立了阳离子交换树脂分离-电感耦合等离子体发射光谱法测定盐湖卤水中偏硅酸含量的方法。将盐湖卤水稀释5倍,加入6 g阳离子交换树脂,静态交换1.5 h,除去卤水中的大量阳离子后,选择Si 251.611 nm为分析谱线,以Y 371.030 nm谱线作为内标进行信号漂移校正,用电感耦合等离子体发射光谱仪能有效测定卤水中偏硅酸的含量。结果表明,校准曲线的线性范围为0.50~200 mg/L,所得回归方程的线性关系良好(r≥0.9994),检出限为0.16 mg/L,结果相对标准偏差(RSD,n=12)为1.8%~4.6%,加标回收率为96.3%~102%。同时采用紫外-可见分光光度法对偏硅酸含量进行方法比对,两种测试结果不存在显著性差异,表明所建立的方法具有良好的准确度。为提高盐湖资源的综合利用提供了可靠的数据支撑。 展开更多
关键词 阳离子交换树脂 电感耦等离子体发射光谱仪 盐湖卤水 偏硅酸
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阳离子树脂交换分离-电感耦合等离子体质谱(ICP-MS)法测定地质石膏样品中硼
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作者 刘金龙 何汉江 +2 位作者 冯慧琳 张霞 王艳超 《中国无机分析化学》 CAS 北大核心 2023年第8期883-887,共5页
为减少由于碱熔盐分对测定元素的干扰,通过考察熔矿体系、阳离子交换树脂加入量、树脂吸附时间、清洗液、同位素等条件的选择,建立了氢氧化钠碱熔-732型阳离子交换树脂交换分离,在线加入铑内标,电感耦合等离子体质谱(ICP-MS)法测定石膏... 为减少由于碱熔盐分对测定元素的干扰,通过考察熔矿体系、阳离子交换树脂加入量、树脂吸附时间、清洗液、同位素等条件的选择,建立了氢氧化钠碱熔-732型阳离子交换树脂交换分离,在线加入铑内标,电感耦合等离子体质谱(ICP-MS)法测定石膏中硼的方法。实验表明,0.5 g样品用氢氧化钠低温升至450℃熔融30 min后继续升温至700℃熔融10 min,分取浸取后溶液的10%(10 mL)上清液,采用5 g 732型阳离子交换树脂静态吸附1 h,在测定过程中选择氨水(2%)清洗进样管,同时选用11 B作为ICP-MS测定的分析同位素。同时由于石膏国家标准物质不包含硼元素的含量,采用高纯硫酸钙分别与岩石标准物质、水系沉积物国家标准物质和土壤国家标准物质混合配制成人工标准物质,结果显示,方法的检出限为0.76μg/g,相对标准偏差(RSD,n=7)为0.90%~1.7%,相对误差为1.56%~3.96%,加标回收率在97.5%~102%,方法快速、准确,记忆效应小,适合石膏中硼元素的测定。 展开更多
关键词 石膏 碱熔 732型阳离子交换树脂 电感耦合等离子体质谱法
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