四钛酸钾晶须吸附废水中重金属离子的研究

以四钛酸钾晶须(PTW)作为去除工业废水中重金属离子铅、镉的吸附剂,考察了吸附剂的用量、吸附时间和酸度对吸附效果的影响.研究结果表明:吸附效率随着吸附剂用量的增加、吸附时间的延长以及pH值的升高而提高,但吸附容量却随着吸附剂用量的增加而降低.水中铅、镉离子在PTW上的吸附可用Freundlich方程进行描述.     

膜分离技术在重金属废水处理中的应用

综述了电渗析、液膜、纳滤、超低压反渗透、胶束增强超滤和水溶性聚合物络合超滤等膜技术在废水处理中的研究和应用概况，分析了膜技术在处理重金属废水中存在的主要问题，并对膜技术处理重金属废水的发展前景作了展望。     

离子交换法治理重金属电镀废水及发展动态

较为详尽地评述了近年来沸石、腐植酸物质、离子交换树脂、黄原酸酯、离子交换纤维等各种离子交换材料的发展，离子交换技术在治理重金属电镀废水中的应用和在各种组合处理技术中的应用研究现状与发展趋势。     

废弃虾壳制备改性甲壳素凝胶球及其对金属离子的吸附性能

以虾壳酶解残渣为原料,经5%盐酸脱钙处理4 h后,用45%氢氧化钠和460 W微波辅助脱乙酰处理10 min,得到脱乙酰度为40.4%的改性甲壳素。将改性甲壳素加入海藻酸钠水溶液中混合均匀,挤压滴入氯化钙水溶液中固化12 h,制备得到直径为1.5~3.2 mm的凝胶小球,研究了该凝胶球对Pb²⁺、Cr³⁺、Ni²⁺、Cu²⁺、Co²⁺和Zn²⁺的吸附效果。结果表明：凝胶球对Cu²⁺、Co²⁺和Zn²⁺的吸附效果最好,300 mg/L重金属离子溶液吸附处理8 h是较适宜的吸附条件,此条件下,Cu²⁺、Co²⁺和Zn²⁺的吸附率分别达到94.2%、75.6%和57.3%。在Cu²⁺-Co²⁺-Zn²⁺共存溶液体系中,凝胶球对3种离子的吸附率均有所提高,Cu²⁺、Co²⁺和Zn²⁺的吸附率分别为95.1%、82.5%和67.5%。     

离子交换法移动处理重金属废水

建立了以离子交换车载移动处理装置为核心的电镀废水处理中心,包括移动处理单元和废水处理车间两部分,为企业提供工业重金属废水的先现场处理,后集中处置的社会化综合服务,实现了工业废水的分散处理与集中处理相结合的互补模式。实际工程运行结果表明,其离子交换车载移动处理装置在现场处理的出水水质较好,整个中心的运行稳定可靠,充分显示了离子交换法集中处理大流量工业废水的优势,经济效益、环境效益和社会效益都较显著。     

Removal and Separation of Some Radionuclides by Poly-acrylamide Based Ce(IV) Phosphate from Radioactive Waste Solutions

Removal of cesium, cobalt, and europium ions from radioactive waste solutions using poly-acrylamide based Ce(IV) phosphate material was investigated using both batch and fixed bed column techniques. The effect of pH, initial metal ion concentration, and temperature had been studied. Simple kinetic and thermodynamic models had been applied from which the mechanism of the process and the thermodynamic parameters were determined. The positive values of enthalpy change, ΔH, obtained for the three metal ions confirmed the endothermic nature of the sorption process and suggested that chemisorption is the predominant sorption mechanism. The high positive values found for the entropy change, ΔS, show the increased randomness at the solid/solution interface. The obtained negative values of free energy change, ΔG, indicating the feasibility and the spontaneous nature of the sorption processes. Breakthrough data were investigated in a fixed bed column at room temperature (298 K) under the effect of various process parameters like bed depth, flow rate, and initial ion concentration. The results showed that the overall bed capacity decreased with increasing flow rate and increased with increasing initial metal ion concentrations and bed depth.     

腐殖酸树脂处理含Zn^2＋、Ni^2＋废水的研究

利用泥炭为原料制备出腐殖酸树脂,在动态条件下,研究了腐殖酸树脂对重金属离子Zn^2＋、Ni^2＋的吸附效果及吸附条件。结果表明,在20℃,流速为4mL／min,pH值为5．0～7．0,含Zn^2＋、Ni^2＋浓度分别为70mg／L的废水经过腐殖酸树脂处理,Zn“、Ni。’去除率可达98％以上,且处理后的废水pH值近中性。含Zn^2＋、Ni^2＋浓度分别为32．5mg／L和29．4mg／L,pH值为5．9的电镀废水经腐殖酸树脂处理后,废水中Zn^2＋、Ni^2＋含量明显低于国家排放标准。     

Effective Removal of Arsenic with Lanthanum(III)- and Cerium(III)-loaded Orange Waste Gels

Abstract

Orange waste has been chemically modified and loaded with lanthanum(III) and/or cerium(III) to examine its adsorption behavior to both As(V) and As(III). Arsenate removal was found to be favored over a pH range of 6 ～ 9.5 while arsenite removal took place at pH values ranging from 9 to 11. The maximum sorption capacity of the gel for As(III) removal was evaluated as 43 mg/g, while that for As(V) was 42 mg/g. Column-mode tests using the La(III)-loaded gel confirmed a complete removal of As(V). A reasonably high adsorption potential within the design criteria makes the present gel an alternative choice for arsenic removal.     

利用农业废弃物作为吸附剂处理重金属离子

介绍了利用农业废弃物作为吸附剂处理重金属离子的研究成果。农业废弃物由于其高效、低成本和可再生等优点,常作为吸附剂用来处理重金属离子,对这些吸附剂进行进一步修饰,以提高其效率,并多次重复利用,以提高其工业规模的适用性。     

海藻酸纤维对铜离子的吸附性能

为了研究不同各类的海藻酸纤维对铜离子的吸附性能,用盐酸及硫酸钠水溶液处理海藻钙纤维,分别得到海藻及海藻酸钙钠纤维,把三种纤维分别与含铜离子的水溶液接触后,在不同的时间段测试溶液中铜离子的深度,结果表示：海藻酸、海藻酸钙及海藻酸钙钠纤维对铜均有较好的吸附性能,其平衡吸附容易分别为68.6mg/g,81.7mg/g和71.0mg/g,海藻酸钙纤维的吸附容量在三种纤维中最高,由于海藻酸钙钠纤维遇水后可以很快地吸水膨胀,其吸附速度较其它两种纤维快.     

离子交换树脂在污酸净化中的应用

以烟气制酸排放污酸为研究对象,使用离子交换树脂脱出污酸中重金属。通过试验得出：该材料对重金属的脱出效率达到99.82%。当材料吸附饱和之后进行反冲洗脱附,脱附之后材料再次恢复吸附重金属之功能,从而开辟了一条污酸净化的技术途径。     

离子交换法分离S-苄基-g-L-谷氨酰-L-半胱氨酸

采用离子交换法对酶法合成的S-苄基-g-L-谷氨酰-L-半胱氨酸(S-Bzl-GGC)进行了分离纯化. 研究了Q Sephrose FF阴离子交换树脂对S-Bzl-GGC的吸附等温线,很好地符合Sips吸附等温线模型. 考察了pH值、洗脱梯度、流速和进样量等条件对纯化效果的影响,建立了一套基于Q Sephrose FF阴离子交换树脂的纯化方案. 结果表明,在pH 8.2、洗脱梯度0~30% B(Tris-HCl缓冲液+1 mol/L NaCl) 12 mL、流速2 mL/min、进样量500 mL的优化条件下,经一步分离,产物纯度可达98.5%,经1H-NMR鉴定产物结构正确.     

巯基泥炭对重金属离子吸附性能研究

以巯基泥炭为分离富集剂 ,对重金属离子的单组分或多组分溶液进行吸附研究 ,探讨了吸附剂的吸附性能、影响吸附因素和吸附机理。实验表明 :巯基泥炭是一种价廉、高效的重金属固体吸附剂 ,在pH =5 ,低温下较未处理泥炭吸附量提高 5倍左右 ;对重金属离子的吸附均表现出Langmuir特征。     

Cesium Removal Demonstration Using Selected Actual Waste Samples from the Hanford Reservation Tank Farm

Abstract

Approximately 40 million curies of Cs‐137 are currently contained in High Level Waste stored in 177 underground storage tanks at the Hanford Nuclear Reservation near Richland, Washington. A series of actual waste, small‐scale column tests were performed to evaluate the performance of a selected ion exchange resin for cesium removal from a range of planned feed streams. These tests demonstrated that the selected cationic resin–SuperLig 644^®‐has more than adequate resin capacity to treat each of three potential feed streams. Furthermore, tests indicate an acceptable mass transfer zone for each of the three types of feed material, and that the elution of the resin can be accommodated within the design criteria for the proposed Waste Treatment Plant.     

利用斜发沸石处理氨氮废水的研究

研究了斜发沸石对NH4^ 吸附和解吸特性，得到了最佳的吸附和解吸条件。结果表明：以斜发沸石作为离子交换剂处理氨氮废水是可行的。     

Removal of Some Heavy Metal Ions Using Grafted Polyurethane Foam

Polyurethane (PU) was modified by grafting a mixture of two monomers acrylonitrile/acrylic acid (AN/AAc) by gamma irradiation method. Effects of various parameters such as, concentration of comonomer composition, grafting yield, gamma irradiation doses, dose rates and pH of adsorbent on the adsorption capacity were studied. Characterizations of the grafted polyurethane (PU-g-AN/AAc) were investigated using infrared (IR) spectroscopic analysis, X-ray diffraction (XRD) and scanning electron microscope (SEM). Moreover, the adsorption capacities of some heavy metals such as, Zn(II), Fe(II), Ca(II), Ni(II), Cu(II) and Pb(II) onto PU-foam and PU-g-AN/AAc were studied. The efficiency of such grafted polyurethane foams for uptaking different previous metal ions was determined and compared with that of natural granular activated carbon (GAC). The uptaking of metal ions was remarkably affected by the pH of the solution, the valances of metal ions, atomic weight and its initial concentrations. Equilibrium isotherms and interruptible diffusivities were investigated through batch experiments in analyzing the uptaking of aqueous solutions of metal ions onto PU foam, grafted PU, and granular activated carbon. The Frundlich constants k and 1/n have been determined for each metal ion to represent both the ability and the affinity of that ions towards the uptaking materials, respectively.     

Vanadium(V) Removal by Adsorption onto Activated Carbon Derived from Starch Industry Waste Sludge

This study examines the adsorption potential of activated carbons for vanadium (V) removal from aqueous solution. Activated carbons were produced via chemical activation of waste treatment sludge from the starch industry. Specific surface area and pore sizes of waste sludge samples were determined through chemical activation and pyrolysis. Experimental data indicated that sludge samples had micropore structure and specific surface area of up to 1196 m²/g. First-order and second-order models were applied to determine adsorption kinetics. Freundlich, Langmuir, and Dubinin–Radushkevich isotherms were used to analyze equilibrium data of adsorption. Equilibrium adsorption data showed the best fit to the Freundlich isotherm. Adsorption of vanadium (V) follows second-order kinetic models. Maximum adsorption was observed at pH 4.0. Langmuir adsorption capacity was found to be 37.17 mg/g. The results of the study indicated that activated carbon obtained from industrial sewage sludge was effective in removing vanadium from aqueous solutions, which creates a significant advantage for treatment of industrial wastewaters and management of solid wastes.     

从酶转化液中分离提取L-苯丙氨酸的工艺研究

利用JK006阳离子交换树脂从酶转化液中分离提取L-苯丙氨酸,对吸附、除杂、洗脱再生等工艺进行研究。吸附损失率几乎为零,对L-苯丙氨酸的吸附量达到97.5g.kg-1湿树脂,L-苯丙氨酸洗脱收率达到94.5%,洗脱液浓度达到28~30g.L-,并对洗脱尾流和再生洗涤水进行了再利用,降低了成本,减少了污染。     

Mechanism of the Adsorption of Ammonium Ions from Aqueous Solution by a Chinese Natural Zeolite

Abstract

The adsorption of ammonium ions onto a Chinese natural zeolite in an agitated batch adsorber was studied. A trial‐and‐error non‐linear method was developed to examine two widely used isotherms, the Langmuir and Freundlich. The data gained from the adsorption system fitted the Freundlich isotherm better. An ion exchange model, describing the relationship among the total metal ions in the solution, NH₄ ⁺ removed from the solution, and ions initially released from the zeolite, was developed for the adsorption system. In addition, a parameter of the ion exchange potential was defined to describe the adsorption mechanism. Ion exchange was the main mechanism that accounted for the adsorption of ammonium ions onto the Chinese natural zeolite.