矿化垃圾生物反应床在废水处理中的应用及其存在的问题

综述了矿化垃圾生物反应床对城市污水、填埋场渗滤液、畜禽废水以及离子交换树脂再生废水处理的工况条件及其处理效果 ,并对其存在的主要问题进行了分析。     

青枯菌野生型菌株和无毒突变株细胞表面的吸附特性(英文)

应用高效离子交换色谱和激光光散射仪检测器(HPLC/MALLS)研究青枯菌野生型菌株79#和无毒突变菌株RS52’对强阴离子交换树脂(SuperQ-650C)的吸附特性.结果显示,这2个菌株在色谱行为和吸附特性方面差异显著.静态吸附试验结果也表明,在相同条件下,79#菌株的吸附速率和吸附量与RS52’菌株不同,79#菌株在60min达到吸附平衡,最大吸附量为1.09×109cfu/g(干树脂);RS52’菌株在120min达到吸附平衡,最大吸附量为2.10×10~9cfu/g(干树脂).进一步采用Langmuir和Freundlich吸附等温线方程比较79#菌株和RS52’菌株与树脂之间的吸附能力,研究结果与静态吸附试验结果以及高效离子交换色谱的分析结果相一致,RS52’菌株与树脂之间显示出更强的吸附力;此外,用Freundlich方程拟合的效果优于Langmuir方程,拟合的曲线与实验数据更吻合.图4表2参16     

离子交换树脂对甲基叔丁基醚的催化水解

研究了D008离子交换树脂对甲基叔丁基醚(MTBE)的吸附作用,以及H-D008树脂对MTBE水解的催化作用,结果表明,Na-D008及H-D008树脂对MTBE都具有较强的吸附作用,吸附等温线呈直线型.H-D008树脂催化MTBE的水解反应符合一级反应动力学.初始浓度增大,表观一级速率常数基本不变;温度升高,表观一级速率常数增大,当温度为25℃,30℃和35℃时,表观一级速率常数分别为0.067 d-1,0.216 d-1和0.343 d-1.H-D008催化水解MTBE反应的活化能为124.8 kJ·mol-1.     

胺型腰果酚醛树脂对Ag~+的吸附

制备了3种胺型腰果酚醛树脂(二乙撑三胺型腰果酚醛树脂(PCD)、己二胺型腰果酚醛树脂(PCE)、己二胺型腰果酚醛树脂(PCH)),采用XPS(X-射线光电子能谱仪)、EA(元素分析仪)、FTIR(傅利叶变换红外光谱分析仪)等手段研究了其结构特征,并考察了其对水溶液中Ag+的吸附行为和机理.结果表明,3种树脂对Ag+有较高的吸附量和吸附作用;在pH值为5.5的条件下,树脂对Ag+的吸附效果最佳;2h内吸附达到平衡;吸附行为均符合Lagergren准二级速率方程;树脂对Ag+的吸附均符合Langmuir等温吸附方程;吸附反应为自发吸热和熵增的过程;可溶性无机盐对树脂吸附Ag+的影响不大;推测其吸附机理是树脂上胺基、羟基与Ag+发生较强的配位作用和较弱的离子交换作用的化学吸附为主.吸附Ag+后的树脂可用硝酸脱附再生;树脂循环使用4次后,吸附率和脱附率仍大于90%.     

垃圾渗滤液离子交换出水对大麦的毒性

本研究主要探讨离子交换树脂处理后,垃圾渗滤液理化指标和生物毒性的变化.选用10、60、80、120、200 g·L~(-1)的树脂处理渗滤液,检测其CODCr、全盐量的变化,探究出水对大麦种子萌发,幼苗根长、芽长、鲜重、干重,根尖细胞有丝分裂及微核率的影响.结果表明,树脂处理可显著降低垃圾渗滤液CODCr和全盐量,投加量为200 g·L~(-1)时去除率达到最大值,分别为88%和55%;渗滤液可以延迟但不会抑制大麦种子萌发;渗滤液对大麦幼苗根长、芽长的抑制作用与树脂投加量及暴露时间呈双重依赖关系,表现为树脂投加量越少,暴露时间越长,抑制作用越显著;相比于大麦的鲜重和干重,其根长、芽长对污染物暴露表现得更为敏感.此外,渗滤液离子交换出水对大麦根尖细胞有丝分裂表现出"低促高抑"的作用,对根尖微核损伤呈现剂量-效应关系.研究选用大麦为模式植物具有一定的实际意义,其结果可为渗滤液的无害化处理及生态风险评价提供理论依据.     

我国主要河流悬浮物样品对镉离子的吸附作用

本项研究的目的主要是:查明我国若干河流悬浮物的组成、性质及其对重金属离子吸附作用的地域分异规律;探讨离子交换吸附与非离子交换吸附的区分方法、各自的速度及其在吸附过程中两者之间的转化问题:研究pH、温度、矿化度对吸附作用的影响。     

新型螯合树脂——木屑柠檬酸脂的合成及其应用

本文选用木屑作为螯合树脂的不溶性骨架材料,与柠檬酸通过酯化、水解反应,主要引入了β-羟基戊二酸功能团,制得了新型螯合树脂——术屑柠檬酸脂(简称CS)。实验表明,CS树脂价廉易得,具有良好的离子交换树脂所要求的理化性质和广谱的重金属选择性,能有效地处理重金属工业废水和回收贵重金属。     

天然水体水相中各金属形态的分离技术及其应用

本文对天然水体水相中各种金属形态的物理、化学分离技术的优缺点进行比较,着重介绍超滤、凝胶色谱、螯合树脂、大网树脂分离技术及其在天然水重金属存在形态的分离分析中的应用。超滤法主要用于分离1.2nm—14nm范围粒径的颗粒;凝胶色谱法主要用于有机金属络合物的粒径分离;螯合树脂法主要用于分离不被螯合的形态;大网树脂则用于吸附分离有机属形态。     

离子交换树脂袋法研究森林土壤硝态氮及其对氮沉降增加的响应

用离子交换树脂袋法，研究了鼎湖山三种森林（马尾松林、马尾松针叶阔叶混交林和季风常绿阔叶林）土壤硝态氮对外加氮的响应特征。结果表明，土壤硝态氮显著地受森林类型、季节和氮处理的影响。整体而言，阔叶林土壤硝态氮极显著高于马尾松林和混交林，而马尾松林和混交林之间的差异则不显著。三种森林土壤硝态氮的季节变化均表现为春季和夏季极显著高于冬季和秋季，而冬季又显著高于秋季。外加氮处理提高土壤硝态氮水平，其中在马尾松林和阔叶林氮处理效应显著。所得结果与直接采集土壤或土壤水测定的硝态氮含量的结果一致，表明离子交换树脂袋法是评价土壤硝态氮水平行之有效的手段之一。     

天然水体中铵态和硝态氮δ15N的测定

介绍了一种天然水体中铵态和硝态氮δ15N的测定方法,包括3个步骤:(1)离子交换法富集水中铵态和硝态氮;(2)蒸馏法进一步提纯铵态和硝态氮;(3)阳离子树脂萃取由转化和蒸馏得到的铵态氮,并将树脂干燥后送入元素分析仪串联质谱(EA-IRMS)测定δ15N.用这种方法处理NH4Cl和KNO3配制的人工模拟水样和野外采集的天然水样,发现δ15N-NH4+和δ15N-NO3-测定的准确性高、重复性好,人工模拟水样δ15N-NH4+的测定值和标准值相差0.560‰,δ15N-NO3-的测定值和标准值相差0.341‰,所有水样重复间的标准偏差在0.008‰—0.384‰之间.测定方法需要的水样体积较少,水样处理速度较快,离子交换后水样中的铵态和硝态氮可长期保存,适合野外天然水体δ15N测定.     

Ammonia removal from low-strength municipal wastewater by powdered resin combined with simultaneous recovery as struvite

• Powdered resin was employed for ammonia recovery from municipal wastewater. • Powdered resin achievedefficient ammonia removal under various working conditions. • Co-existing cations indicated competitive adsorption of ammonia. • Ammonia was recoveredby two-stage crystallization coupled with ion exchange. Low-strength municipal wastewater is considered to be a recoverable nutrient resource with economic and environmental benefits. Thus, various technologies for nutrient removal and recovery have been developed. In this paper, powdered ion exchange resin was employed for ammonia removal and recovery from imitated low-strength municipal wastewater. The effects of various working conditions (powdered resin dosage, initial concentration, and pH value) were studied in batch experiments to investigate the feasibility of the approach and to achieve performance optimization. The maximum adsorption capacity determined by the Langmuir model was 44.39 mg/g, which is comparable to traditional ion exchange resin. Further, the effects of co-existing cations (Ca²⁺, Mg²⁺, K⁺) were studied. Based on the above experiments, recovery of ammonia as struvite was successfully achieved by a proposed two-stage crystallization process coupled with a powdered resin ion exchange process. Scanning electron microscopy (SEM) and X-ray diffractometry (XRD) results revealed that struvite crystals were successfully gained in alkaline conditions (pH= 10). This research demonstrates that a powdered resin and two-stage crystallization process provide an innovative and promising means for highly efficient and easy recovery from low-strength municipal wastewater.     

Advancing ion-exchange membranes to ion-selective membranes: principles,status, and opportunities

● IEM ion/ion selectivities of charge, valence, & specific ion are critically assessed. ● Ion/molecule selectivities of ion/solvent and ion/uncharged solute are reviewed. ● Approaches to advance the selectivities through sorption and migration are analyzed. ● The permeability-selectivity tradeoff appears to be pervasive. ● Ion/molecule selectivities are comparatively underdeveloped and poorly understood. Ion-exchange membranes (IEMs) are utilized in numerous established, emergent, and emerging applications for water, energy, and the environment. This article reviews the five different types of IEM selectivity, namely charge, valence, specific ion, ion/solvent, and ion/uncharged solute selectivities. Technological pathways to advance the selectivities through the sorption and migration mechanisms of transport in IEM are critically analyzed. Because of the underlying principles governing transport, efforts to enhance selectivity by tuning the membrane structural and chemical properties are almost always accompanied by a concomitant decline in permeability of the desired ion. Suppressing the undesired crossover of solvent and neutral species is crucial to realize the practical implementation of several technologies, including bioelectrochemical systems, hypersaline electrodialysis desalination, fuel cells, and redox flow batteries, but the ion/solvent and ion/uncharged solute selectivities are relatively understudied, compared to the ion/ion selectivities. Deepening fundamental understanding of the transport phenomena, specifically the factors underpinning structure-property-performance relationships, will be vital to guide the informed development of more selective IEMs. Innovations in material and membrane design offer opportunities to utilize ion discrimination mechanisms that are radically different from conventional IEMs and potentially depart from the putative permeability-selectivity tradeoff. Advancements in IEM selectivity can contribute to meeting the aqueous separation needs of water, energy, and environmental challenges.     

Synthesis and characterization of an ion exchanger based on tamarind kernel powder and its application for removal of some metal ions from industrial effluents

A resin synthesized from tamarind kernel powder possesses high selectivity for metal ions. Distribution coefficients for some metal ions has been determined by the batch method. The influence of pH on ion exchange capacity and K _d value of metal ions were studied. The resin has been characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, chemical composition and ion exchange capacity (IEC). The selectivity order is Pb²⁺?>?Cu²⁺?>?Fe²⁺?>?Zn²⁺?>?Ni²⁺. Removal of metal ions from the aqueous solution and from effluents of a steel mill has been studied.     

金属浓度,半透膜孔径,水温及配位体对半透膜囊吸收铜的影响

在实验室条件下，研究了影响树脂－半透膜囊吸收铜的主要因素，重点探讨了水相铜含量，半透膜孔径，温度以及天然河水中的有机配位体对吸收的影响。结果表明，半透膜囊吸收量与水相游离铜浓度，水温及半透膜孔径的非整数次幂成正比，其中包括ＥＤＴＡ，河水富里酸，以及河水中的各种天然有机物在内的配位体均与铜生成不能被半透膜囊吸收的络合物，研究结果进一步证实了半透膜囊对水环境中游离态微量金属进行长期监测的可行性。     

The Adsorption of Lead and Copper from Aqueous Solution on Modified Peat–Resin Particles

Raw peat was modified with sulfuric acid, then mixed modified with resin to prepare the modified peat–resin particles. Using the batch experimental systems, the removal of heavy metals (copper and lead) on the modified peat–resin particles was investigated. The data of the adsorption isotherm could be fitted by the Langmuir equation well. The adsorption rate of heavy metals on modified peat–resin particles was very swift. The removal processes of heavy metals on modified peat–resin particles could be well described by pseudo-second order model. The adsorption rate of lead was affected by the initial heavy metal concentration, initial pH, particle size, agitation speed and particle mass. In the adsorption of heavy metals (lead and copper) on the modified peat–resin particles, ion exchange was the major reaction mechanism. Desorption data showed that the lead adsorbed by modified peat–resin particle could be desorbed by 0.5 N or 1.0 N HNO₃. The desorption rate was swift. The experiments indicated that the modified peat–resin particles have great potential for the removal of heavy metals from wastewater.     

城市污水二级硝化出水的离子交换脱氮除磷

以城市污水二级硝化出水为原水,对比研究了3种强碱性阴离子交换树脂(201×4、D296、D301T)动态脱氮除磷情况,并以201×4树脂为模式树脂考察了树脂活化方式(常规酸碱交替活化与NaCl再生液活化)、腐殖酸(HA)浓度(1.1,2.8和9.4 mg·l~(-1))对树脂动态脱氮除磷的影响.结果表明,3种树脂都具有较好的脱氮除磷效果,达到TP穿透点(0.1 mg·l~(-1),去除率92%)时,201×4树脂具有最大的穿透体积(418 BV),但其对NO_3~--N的去除率(69%)明显低于其它树脂(97%-98%);3种树脂对SO_4~(2-)和HA的去除率分别为97%-99%,71%-80%;常规酸碱活化使树脂穿透体积较再生液活化仅提高了12%;超滤膜法和臭氧氧化法预处理对原水HA的去除率分别为27%和68%;原水HA浓度增加使树脂穿透体积从28lBV降至239BV,同时NO_3~-去除率从80%上升至92%.     

球形复合无机离子交换剂的制备及其对Sr2+和Cs+的去除

用溶胶－凝胶的方法制备了水合二氧化钛－水合五氧化二锑（HTO－HAP）球形复合无机离子交换剂，研究了其对Sr^2 和Cs^ 的离子交换性能，并对其组成，结构及稳定性作了初步的研究。结果表明，此种球形交换剂机械强度好，适合装柱，在弱酸性条件下对Sr^2 和Cs^ 有较好的交换容量。     

Preparation of a novel anion exchange group modified hyper-crosslinked resin for the effective adsorption of both tetracycline and humic acid

A novel hyper-crosslinked resin (MENQ) modified with an anion exchange group was prepared using divinylbenzene (DVB) and methyl acrylate (MA) as comonomers via four steps: suspension polymerization, post-crosslinking, ammonolysis and alkylation reactions. The obtained resin had both a high specific surface area (793.34 m²·g^-1) and a large exchange capacity (strong base anion exchange capacity, SEC: 0.74 mmol·g^-1, weak base anion exchange capacity, WEC: 0.45 mmol·g^-1). XAD-4 was selected as an adsorbent for comparison to investigate the adsorption behavior of tetracycline (TC) and humic acid (HA) onto the adsorbents. The results revealed that MENQ could effectively remove both TC and HA. The adsorption capacity of XAD-4 for TC was similar to that of MENQ, but XAD-4 exhibited poor performance for the adsorption of HA. The adsorption isotherms of TC and HA were well-fitted with the Freundlich model, which indicated the existence of heterogeneous adsorption through cation-π bonding and π–π interactions. The optimal solution condition for the adsorption of TC was at a pH of 5–6, whereas the adsorption of HA was enhanced with increasing pH of the solution.     

D201树脂对双组分萘系化合物的吸附分离

用D201强碱性阴离子交换树脂自双组分水溶液中选择吸附分离1-氨基-2-萘酚-4-磺酸(1,2,4-酸)和2-萘酚,考察了溶液pH值、浓度、温度、树脂床高及流速等因素对吸附和分离系数的影响.结果表明,在pH 3—6时,树脂对1,2,4-酸有较高的吸附量及吸附选择性,利于1,2,4-酸与2-萘酚的选择性吸附分离.温度对吸附的影响较小,等温吸附规律符合Freundlich模型.动态吸附表明,至1,2,4-酸的泄漏点时,吸附流出液中几乎只含2-萘酚,1,2,4-酸被吸附于树脂上.随着树脂床层的增长或初始浓度和流速的减小,都使泄漏点推迟及分离系数提高.载酚酸的树脂柱可用15%质量比的NH4Cl和20%体积比的乙醇混合液定量洗脱1,2,4-酸.     

三氮的离子色谱法连续测定研究

本文首次提出用电导检测器和紫外检测器串联,对氮的三种形态(N-NO_2~-,N-NO_3~-,N-NH_4~+)进行连续测定;盐酸/甘氨酸作淋洗液,HPIC-CS_5作分离柱,建立了同时测定“三氮”灵敏的色谱方法,方法的线性相关系数大于0.999,各离子的相对标准偏差均小于0.5％,对样品的测定,回收率均在100％％+5％以内,与标准方法比较,结果颇为一致。