洗相废水中银回收技术研究

采用电解法和离子交换法回收洗相废水中的银.结果表明,电解法对高浓度含银洗相废水的银回收处理是一种行之有效的方法.对于中低浓度洗相废水中的银的回收,采用4%硫酸再生IRA-68离子交换树脂,树脂的交换能力可以增加4倍,再生时由于已交换的银被直接固定在树脂上,结果使得再生剂处置和银回收过程更加简单方便.IRA-68离子交换树脂回收中低浓度洗相废水中银的技术具有银回收效率更高、离子交换运行时间更长和操作更为简便等优点,使得传统的离子交换技术得到极大的改进和提高.     

滦河水体溶解性有机物的综合分级表征及其混凝去除过程

天然水体溶解性有机物(DOM)是微污染物的潜在载体,是消毒副产物的主要前驱物,自身又可能成为微污染物,因此研究其内在特性和去除机理有着重要的基础性科学意义.本研究综合利用化学、物理分级方法(即树脂和超滤分级法),对中国北方典型饮用水源--滦河水体的DOM进行全面分级表征.此水体DOM基本化学分级特征是憎水酸(HoA)、亲水性物质(HiM)含量较高,且具有季节稳定性;其物理分级特征是分子量＜1 kDa及3 kDa～10 kDa的组分含量较高,也表现出一定的时间稳定性.选用工业聚合铝(PAC)研究此DOM的基本混凝特征和内在混凝机理,结果表明,强憎水部分HoA及3 kDa～10 kDa间的有机物较易被去除,而较大分子量范围10 kDa～30 kDa间的有机物去除率较低,说明混凝过程中此DOM的物理性质不起主要作用,而化学性质更为重要.特别对DOM各组分作进一步(结合)分级研究,发现HoA主要在＞10 kDa范围.＜1 kDa的有机物中主要为HiM,但其中还含有HoA和弱憎水酸(WHoA),这使特定条件下部分＜1 kDa有机物被混凝去除成为可能.另外,HoA中按分子量大小仍可分为易去除和难去除部分,但分布不连续,易去除部分在3 kDa～10 kDa和＞30 kDa区间,而其10 kDa～30 kDa部分较难去除,说明可能存在其他结构性影响因素,值得深入研究.     

Transformations of particles, metal elements and natural organic matter in different water treatment processes

Characterizing natural organic matter （NOM）, particles and elements in different water treatment processes can give a useful information to optimize water treatment operations. In this article, transformations of particles, metal elements and NOM in a pilot-scale water treatment plant were investigated by laser light granularity system, particle counter, glass-fiber membrane filtration, inductively coupled plasma-optical emission spectroscopy, ultra filtration and resin absorbents fractionation. The results showed that particles, NOM and trihalomethane formation precursors were removed synergistically by sequential treatment of different processes. Preozonation markedly changed the polarity and molecular weight of NOM, and it could be conducive to the following coagulation process through destabilizing particles and colloids; mid-ozonation enhanced the subsequent granular activated carbon （GAC） filtration process by decreasing molecular weight of organic matters. Coagulation-flotation and GAC were more efficient in removing fixed suspended solids and larger particles; while sand-filtration was more efficient in removing volatile suspended solids and smaller particles. Flotation performed better than sedimentation in terms of particle and NOM removal. The type of coagulant could greatly affect the performance of coagulation-flotation. Pre-hydrolyzed composite coagulant （HPAC） was superior to FeCl3 concerning the removals of hydrophobic dissolved organic carbon and volatile suspended solids. The leakages of flocs from sand-filtration and microorganisms from GAC should be mitigated to ensure the reliability of the whole treatment system.     

Adsorption thermodynamics and kinetic investigation of aromatic amphoteric compounds onto different polymeric adsorbents

The adsorption behavior of p-aminobenzoic acid and o-aminobenzoic acid onto the different polymeric adsorbents was systematically investigated as a function of the solution concentration and temperature.Experimental results indicated that the equilibrium adsorption data of the four polymeric adsorbents fitted well in the Freundlich isotherm.The adsorption capacity of multi-functional polymeric adsorbent NJ-99 was the highest,which might be attributed to the strong hydrogen-bonding interaction between the amino groups on the resin and the carboxyl group of aminobenzoic acid.The adsorption capacity of o-aminobenzoic acid onto any adsorbent was higher than p-aminobenzoic acid.Thermodynamic studies suggested the exothermic,spontaneous physical adsorption process.Adsorption kinetics results showed that the adsorption followed the pseudo-second-order kinetics model and the intraparticle mass transfer process was the rate-controlling step.     

载钯螯合树脂的制备、表征及其降解多溴联苯醚的初步研究

以聚丙烯醛-异烟酰腙螯合树脂为高分子载体, 利用其活性基团对钯的选择性富集分离性能, 将金属元素钯键合到高分子载体上, 制备一种含钯树脂材料(树脂1), 并进一步原位还原得到还原态的载钯树脂(树脂2)。利用红外光谱、扫描电镜和X射线衍射等对以上2种含钯树脂材料进行了分析表征,并考察了它们对持久性有机污染物(POPs)多溴联苯醚(PBDEs)的脱溴降解性能。结果表明,2种树脂对BDE₂₀₉均有降解活性, 其中树脂1的降解性能比树脂2的降解性能要高, 树脂中钯的氧化形态可能对BDE₂₀₉的催化降解起主要作用。     

工业废水中测定六价铬的预处理技术

根据复合絮凝剂与阳离子交换树脂两者在分离与处理技术上所起的不同作用 ,提出了将两法联合用作工业废水中测定Cr6 的预处理技术 ,通过一系列条件试验 ,确定最佳预处理条件。结果表明 ,该法具有去色、去浊率高 ,分离效果佳 ,排除干扰离子能力强 ,分析样品重现性好 ,准确度高 ,操作简便、快捷的优点。     

PAN-S树脂富集钴的分光光度法测定研究

研究了PAN—S浸渍树脂对Co^2＋的吸附性能。Co^2＋吸附pH值范围为4．7—9．2,最佳pH值为5．4;达到最大吸附容量需25min,树脂对Co^2＋平衡吸附容量是98mg／g干树脂,达到最大吸附容量平衡时用0．1mol／L的HNO,洗脱,洗脱率达98％。该方法建立了PAN—S-树脂富集一分离钴离子的分光光度测定方法,结果令人满意。     

处理含硫废水的新型催化剂

合成了适合处理含硫废水的固相催化剂,考察了催化剂的稳定性、活性及对实际废水的处理效果,开了含硫废水处理的一条新途径。     

螯合树脂去除丙烯酸丁酯废水中的二价阳离子

采用氨基膦酸螯合树脂C-900去除丙烯酸丁酯废水中的二价阳离子,考察了吸附温度和废水流量对树脂动态吸附性能的影响,并用Thomas模型进行动态吸附数据的拟合分析。实验结果表明,在吸附温度为35℃、废水流量为15SV的条件下,处理后出水中3种二价阳离子总质量浓度为1.0mg/L时的穿透体积为240BV,达到穿透体积时树脂对Ca²⁺,Mg²⁺,Cu²⁺的去除率分别为100%,99.2%,99.8%。     

树脂固定床吸附含酚废水预测模型研究

针对应用于实际工业化的树脂固定床吸附研究较少,而与之相关的固定床吸附穿透曲线可以用来确定固定床吸附操作参数,为固定床的设计和实际操作提供指导。通过对恒定波振荡理论和吸附等温方程的联合,来预测固定床吸附穿透曲线;并研究了不同操作条件对大孔弱碱树脂吸附对硝基酚穿透曲线预测模型的影响。以期望为树脂固定床的设计和实际工业应用产生指导意义。