The curve of ion exchange ratio(%)-pH of the interaction between suspended particles with Cd(II) in the Yellow River

The curve of ion exchange ratio(%)-pH of the interactionbetween suspended particles with Cd(II) in the Yellow River wasstudied. The effects of lysine on this curve have been alsoinvestigated. The results showed that (1) Cadmium in Cd(OH)+ formin the suspended particles exchanges with the cations.The exchangeratio of Cd2+ is nearly at its greatest value in the range of pH(8.0-8.5) in natural aquatic system; (2) Ion exchange ratiodecreases as the concentration of Cd2+ raises from 8.9×10-6 mol/L to 2x8.9 x 10-6mol/L; (3) At the lysine concentration of 6.8x10-6 mol/L, it can promote the ion exchange ratio; (4) Adsorption of thesuspended particles to cadmium is weaker in seawater and Jin ShaRiver than in the Yellow River.     

天然斜发沸石对溶液中NH4+的物化作用机理

选择中国浙江缙云天然斜发沸石为试验材料,以摇床试验和离子跟踪监测,研究了斜发沸石对溶质NH4+的物化作用机理.在天然斜发沸石对溶液中NH4+的作用过程中,离子交换作用决定了NH4+的全部转移量,沸石晶体内Na+和Ca2+与溶液中NH4+的交换量占总离子交换量的97%以上.对于粒径1.0~3.2mm的沸石,交换反应前3h时可完成83%的Na+交换量和50%的Ca2+交换量.     

离子交换树脂静态吸附二甲胺的研究

通过静态吸附实验,研究了二甲胺在ZGSPC106型细颗粒树脂上的吸附行为,从热力学和动力学角度对吸附过程进行了分析,并用红外光谱的方法探讨了树脂吸附二甲胺的机理.结果表明,Langmuir等温方程能够很好的拟合吸附平衡数据,热力学参数表明该吸附可自发进行,且为熵增加的吸热过程,293K温度下树脂的静态饱和吸附容量为138.89mg/g(干树脂);吸附动力学符合准二级动力学模型,颗粒扩散是树脂吸附二甲胺速率的主要控制步骤.     

磁性树脂对地下水中硝酸盐的去除效能及影响因素

利用小试实验研究了磁性离子交换树脂对水中硝酸盐的去除效能,并探讨了地下水中常见有机物及无机离子对其去除效能的影响.结果表明,磁性离子交换树脂对纯水中20mg/L的NO3--N的交换容量为55.91mg/mL,且去除速率较快,10min基本达到去除平衡;地下水中的腐殖酸类有机物对NO3--N的去除基本没有影响,而常见阴离子具有较明显的影响,其影响程度为SO42->CO32->Cl->HCO3-;针对徐州某水厂地下水的去除研究表明,通水倍数为500BV时磁性离子交换树脂对地下水中NO3--N的去除率约为50%左右.综上,磁性离子交换树脂可以作为去除地下水中的硝酸盐一种处理技术.     

阳离子改型蛭石的铵离子交换平衡特性

对经Na^＋，Ca^2＋、Mg^2＋等不同离子处理的改型蛭石在不同pH和温度条件下进行了铵离子交换性能的研究。结果表明，交换反应均在前60min速率最快，约120min就趋向于平衡：铵离子交换总量均随pH变化而波动，在pH=7点上取最大值，且全交换容量按镁型蛭石、钙型蛭石，钠型蛭石顺序依次增大，每100g蛭石分别为59.32，71.89、92.85mmol；改型蛭石对NH^＋4等温交换吸附与Langmuir方程相符。表明改型蛭石对NH^＋4的吸附主要是单分子层的化学吸附。     

沸石在水处理中的应用

本文介绍了中国沸石的种类及其分布概况,以产自甘肃省白银市的斜发沸石为研究对象,对其化学组成及分子晶格形式作了较为详尽的阐述,经实验室检测出其化学组成及物化指标,且对沸石作为吸附荆、离子交换剂、催化剂处理废水的作用机理进行了深入的探讨,对于天然沸石改性进行了实验研究,得出采用氯化钠溶液对天然沸石改性的效果比较理想,改性溶液的最佳浓度为0.9mol/L,研究沸石在沸水处理领域中的应用,分析了沸石处理各类废水的机理,并对沸石处理废水的前景进行了展望.     

离子交换萃取-气质联用测定凝结水中有机酸

以某制药厂含有机酸凝结水为研究对象,建立了气质联用(GC-MS)测定有机酸的方法,研究了不同的进样方式及pH条件对离子交换萃取效率的影响。研究结果表明:GC-MS检测得到凝结水中含有甲酸、乙酸、丙酸、丁酸、戊酸、己酸、异丁酸和2-甲基丁酸8种有机酸,GC-MS能将这8种有机酸完全分开;GC-MS检测得到标准曲线线性为:0.999、0.999、0.999、0.999、0.999 8、0.999 8、0.999 7、0.999 2,标准偏差分别为0.05、0.09、0.05、0.02、0.02、0.05、0.06、0.06;调节水样pH值为7且进样0.2 mL时有机酸的回收率分别为92.55%、83.48%、92.38%、101.4%、93.82%、97.24%、92.87%、93.81%。     

水热条件对粉煤灰沸石离子交换性能的影响

沸石的离子交换性能是决定其应用价值的一个重要指标。为衡量粉煤灰沸石的应用性能,本研究主要考察了反应温度、反应时间以及添加剂等水热反应条件对合成粉煤灰沸石产品离子交换性能(CEC,Cation Exchange Capacity)的影响。结果表明,产品的CEC值随着反应温度和反应时间增加而增大,至120℃、6h达到最大。添加剂十六烷基三甲基溴化铵和95%乙醇有效促进了NaP1沸石的结晶过程,均可使产品CEC值提高10%以上。合成NaP1型粉煤灰沸石的最佳水热反应条件为:反应温度120℃,反应时间6h,液固比(mL/g)为8,氢氧化钠浓度为2mol/L,95%乙醇作为添加剂。所得粉煤灰沸石产品CEC值达到最大值198.31cmol/kg。     

无机离子交换材料吸附锶、铯研究进展

90Sr、137Cs的去除是放射性废水处理研究的重点。无机离子交换技术凭其所特有的优势已经成为较为经济和适宜的手段之一。本文介绍了常用的无机离子交换材料如沸石、杂多酸盐、复合离子交换剂、金属亚铁氰化物及铁氰化物、多价金属磷酸盐等的应用现状,探讨了无机离子交换材料吸附锶、铯的研究进展和发展方向,以期对以后的研究有所帮助。     

沸石在水处理中的应用

本文介绍了中国沸石的种类及其分布概况，以产自甘肃省白银市的斜发沸石为研究对象，对其化学组成及分子晶格形式作了较为详尽的阐述，经实验室检测出其化学组成及物化指标，且对沸石作为吸附剂、离子交换剂、催化剂处理废水的作用机理进行了深入的探讨，对于天然沸石改性进行了实验研究，得出采用氯化钠溶液对天然沸石改性的效果比较理想，改性溶液的最佳浓度为0．9mol/L。研究沸石在沸水处理领域中的应用，分析了沸石处理各类废水的机理，并对沸石处理废水的前景进行了展望。     

离子膜辅助电催化氧化法预处理焦化废水的研究

焦化废水是属有毒有害、难降解的有机废水,常规的生物处理工艺对其去除效果不甚理想,从而导致出水中难降解污染物含量较高,COD和NH3-N不能达标。论文针对焦化废水的水质特点,采用离子膜电解技术进行预处理。对焦化废水中主要污染物苯酚降解效果的几种因素进行了研究,得出了苯酚降解的最佳工艺条件并在此工艺参数下,对模拟焦化废水电解2.5h,苯酚、COD的去除率分别为84%,45%,氨氮去除率和回收率别为99.5%和96.5%,总能耗27kwh/m3,可以为后续生化处理大大减轻负担,采用该方法作为焦化废水的预处理手段比较经济合理。     

天然矿石毒重石吸附硫酸盐废水的试验研究

利用天然矿石毒重石对硫酸盐废水进行吸附处理，在废水的pH=9，停留时间为80min左右时，该吸附剂具有较好的吸附效果。且该离子交换吸附法具有成本低、操作简单、无二次污染的优点。     

离子交换技术在重金属废水处理中的应用

重金属废水由于所含重金属对人类和环境的危害,需要对其进行处理。化学沉淀法被广泛应用于重金属废水的处理过程,但采用化学沉淀法处理重金属废水时,会产生大量的重金属污泥,需要妥善处理或处置。离子交换技术处理重金属废水,既可实现废水中重金属的去除,有可回收废水中的重金属,避免化学沉淀法处理重金属废水时产生大量的污泥。离子交换树脂对废水中重金属离子的选择性分离,可以更好的实现废水中重金属离子的处理和重金属离子的回收。     

膜电解法处理含镍废水的研究

镍作为合金化元素得到广泛应用,不锈钢占全球镍消费量的大约一半,因价格昂贵,故镍的回收有很大的意义.采用单阴膜电解法对含镍废水中的镍离子进行电沉积回收,研究膜种类、电流密度、温度、电解时间、搅拌速度等因素对镍离子去除效果.实验结果表明:在电流密度为60 A/m2,温度为40℃,pH为3.5,电解时间为5h,搅拌速度为300 r/min的条件下,镍离子去除率可达到85.3％,阴极电流效率为56.8％.     

Removal of bentazone from micro-polluted water using MIEX resin: Kinetics, equilibrium, and mechanism

The contamination of surface and ground water by bentazone has attracted increasing global concern in recent years. We conducted a detailed investigation using MIEX resin to eliminate bentazone from waters. Batch experiments were carried out to evaluate the e ect of process parameters, such as retention time, resin amount, and initial pesticide concentration, on removal e ciency of bentazone. Results showed the sorption process was fast and bentazone could be e ciently removed in 30 minutes. The kinetic process of bentazone sorption on MIEX resin was well described by pseudo second-order model and intraparticle di usion was the rate controlling step. The MIEX resin possessed the highest sorption capacity of 0.2656 mmol/mL for bentazone according to Langmuir fitting. Bentazone is a hydrophobic ionizable organic compound, and both ionic charge and hydrophobic aromatic structure governed the sorption characteristics on MIEX resin. The di erent removal e ciencies of ionic and non-ionic pesticides, combined with the charge balance equations of bentazone, SO4 2??, NO3?? and Cl??, indicated that removal of bentazone using MIEX resin occurred primarily via ion exchange.     

Pb（II） biosorption using chitosan and chitosan derivatives beads： Equilibrium, ion exchange and mechanism studies

The study examined the adsorption of Pb(II) ions from aqueous solution onto chitosan, chitosan-GLA and chitosan-alginate beads. Several important parameters influencing the adsorption of Pb(II) ions such as initial pH, adsorbent dosage and di erent initial concentration of Pb(II) ions were evaluated. The mechanism involved during the adsorption process was explored based on ion exchange study and using spectroscopic techniques. The adsorption capacities obtained based on non–linear Langmuir isotherm for chitosan, chitosan-GLA and chitosan-alginate beads in single metal system were 34.98, 14.24 and 60.27 mg/g, respectively. However, the adsorption capacity of Pb(II) ions were reduced in the binary metal system due to the competitive adsorption between Pb(II) and Cu(II) ions. Based on the ion exchange study, the release of Ca2+, Mg2+, K+ and Na+ ions played an important role in the adsorption of Pb(II) ions by all three adsorbents but only at lower concentrations of Pb(II) ions. Infrared spectra showed that the binding between Pb(II) ions and the adsorbents involved mostly the nitrogen and oxygen atoms. All three adsorbents showed satisfactory adsorption capacities and can be considered as an e cient adsorbent for the removal of Pb(II) ions from aqueous solutions.     

Pb(Ⅱ) biosorption using chitosan and chitosan derivatives beads: Equilibrium, ion exchange and mechamsm studies

The study examined the adsorption of Pb(Ⅱ) ions from aqueous solution onto chitosan, chitosan-GLA and chitosan-alginate beads.Several important parameters influencing the adsorption of Pb(Ⅱ) ions such as initial pH, adsorbent dosage and different initial concentration of Pb(Ⅱ) ions were evaluated. The mechanism involved during the adsorption process was explored based on ion exchange study and using spectroscopic techniques. The adsorption capacities obtained based on non-linear Langmuir isotherm for chitosan, chitosan-GLA and chitosan-alginate beads in single metal system were 34.98, 14.24 and 60.27 mg/g, respectively. However,the adsorption capacity of Pb(Ⅱ) ions were reduced in the binary metal system due to the competitive adsorption between Pb(Ⅱ) and Cu(Ⅱ) ions. Based on the ion exchange study, the release of Ca~(2+), Mg~(2+), K~+ and Na~+ ions played an important role in the adsorption of Pb(Ⅱ) ions by all three adsorbents but only at lower concentrations of Pb(Ⅱ) ions. Infrared spectra showed that the binding between Pb(Ⅱ) ions and the adsorbents involved mostly the nitrogen and oxygen atoms. All three adsorbents showed satisfactory adsorption capacities and can be considered as an efficient adsorbent for the removal of Pb(Ⅱ) ions from aqueous solutions.     

新型环境材料提铯离子筛的铯离子交换性能初探

研究了提铯离子筛的颗粒性质对铯离子的交换容量和分配系数的影响，以及提铯离子筛在强酸介质中的稳定性和交换性能；探讨了在大量氢离子或钠离子存在时提铯离子筛对铯离子的选择性。实验结果表明提铯离子筛为多孔无定形物质，其对铯离子的交换容量和分配系数，随着颗粒粒度的减小而增加，但是酸度和钠离子的影响有限。在与模拟高放废液的静态交换中，提铯离子筛对铯离子的交换率可高达96％以上，基本达到了从高放废液中提取^137Cs的指标。     

选择性离子交换法脱除水中NH3-N

采用储量较大的黑龙江省嫩江天然斜发沸石,对其脱除NH_3-N的能力、预处理及洗脱再生方法、交换平衡、交换动力学等进行系统的研究,并对沸石床层的交换过程进行数学模型计算。     

饮用水中硝酸盐去除方法比较

本文综述了饮用水中硝酸盐的各种去除方法及其优缺点.通过分析比较,认为离子交换法和生物反硝化法都可用于大规模生产饮用水,但最有发展前途目前研究最多的是生物反硝化法.该法将硝酸盐转化为氮气,无废液产生,处理费用低.但异氧反硝化法需进行复杂的后处理除去过量的有机物,自养反硝化法会造成出水硫酸盐含量增高.