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41.
铁炭微电解预处理电路板废水 总被引:3,自引:0,他引:3
采用铁炭微电解法预处理电路板废水.结果表明,在进水pH为2.00、铁炭质量比为4:1、振荡时间为20 min的铁炭微电解静态实验最佳条件下,絮凝出水COD去除率为30%;在进水pH为2.00、铁炭质量比为4:1、水力停留时间为50 min的铁炭微电解柱动态实验最佳条件下,连续曝气.絮凝出水COD为11021 mg/L,COD去除率约为34%,BOD5/COD从0.12上升到0.32,可生化性提高,Cu2+质量浓度从9.11 mg/L下降至0.76 mg/L,降低了废水的生物毒性,为生化处理创造了条件. 相似文献
42.
不同高级氧化法对水中低浓度药物甲硝唑降解过程的比较 总被引:3,自引:0,他引:3
采用UV、H2O2、UV/H2O2、Fenton、UV/Fenton和UV/TiO2方法,对水中低浓度的药物甲硝唑进行降解。通过HPLC和UV-Vis光谱得到的甲硝唑去除率。详细讨论了Fe2+、TiO2和H2O2的初始浓度以及溶液的初始pH值对降解效率的影响。结果表明,UV/Fenton和UV/TiO2 2种系统对水中低浓度甲硝唑均有很好的去除效果,但前者的光催化效率更高。在甲硝唑浓度=6 μmol/L,H2O2和Fe2+的初始浓度分别为0.5 mg/L和2.94 μmol/L,pH=4的条件下,UV/Fenton方法对甲硝唑水溶液光催化的最佳效率为95.8%。 相似文献
43.
环糊精聚合物对苯胺的吸附和脱附性能研究 总被引:2,自引:1,他引:1
以环氧氯丙烷为交联剂,合成和表征了β-环糊精聚合物(β-CDP),从动力学和热力学角度研究了β-CDP对苯胺的吸附性能。研究结果表明,β-CDP对水溶液中的苯胺具有一定的吸附量。用Langmuir, Freundlich和DubininRadushkevich(D-R)吸附等温式拟合了平衡等温数据,并计算出每个模型的参数。苯胺在β-CDP上的吸附符合D-R方程,吸附过程是热力学自发行为。在乙醇中,β-CDP的脱附能力很强,且可循环使用多次。 相似文献
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Effective removal of coordinated copper from wastewater using a new dithiocarbamate-type supramolecular heavy metal precipitant 总被引:1,自引:0,他引:1
A new dithiocarbamate-type heavy metal precipitant, sodium 1,3,5-hexahydrotriazinedithiocarbamate (HTDC), was prepared and used to remove coordinated copper from wastewater. In the reported dithiocarbamate-type precipitants, HTDC possesses the highest percentage of the effective functional groups. It could effectively precipitate copper to less than 0.5 mg l−1 from both synthetic and actual industrial wastewater containing CuEDTA in the range of pH 3–9. UV–vis spectral investigation and elemental analysis suggested that the precipitate was a kind of coordination supramolecular compound, [Cu3(HTDC)2]n. The toxicity characteristic leaching procedure (TCLP) and semi-dynamic leaching test (SDLT) indicated that the supramolecular precipitate was non-hazardous and stable in weak acid and alkaline conditions. Tests of an anion exchange resin D231 provided a clue to simultaneously remove excess HTDC and residual CuEDTA in practical process of wastewater treatment. 相似文献
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Yongqiang Yang Zhuli Liu Fanrong Chen Shijun Wu Ling Zhang Mingliang Kang Jie Li 《Environmental monitoring and assessment》2014,186(12):8089-8107
Twenty-four major and trace elements and the mineralogical composition of four sediment cores along the Pearl River and estuary were analyzed using ICP-AES, ICP-MS, and X-ray diffraction (XRD) to evaluate contamination levels. The dominant minerals were quartz, kaolinite, and illite, followed by montmorillonite and feldspars, while small amounts of halite and calcite were also observed in a few samples. Cluster analysis (CA) and principal component analysis (PCA) were performed to identify the element sources. The highest metal concentrations were found at Huangpu, primarily due to wastewater treatment plant discharge and/or the surreptitious dumping of sludge, and these data differed from those of other sources. Excluding the data from Huangpu, the PCA showed that most elements could be considered as lithogenic; few elements are the combination of lithogenic and anthropogenic sources. An antagonistic relationship between the anthropogenic source metals (K, Ba, Zn, Pb, Cd, Ag, Tl, and U) and marine source metals (Na, Mg, Ti, V, and Ca) was observed. The resulting normalized Al enrichment factor (EF) indicated very high or significant pollution of Cd, Ag, Cu, Zn, Mo, and Pb at Huangpu, which may cause serious environmental effects. Conflicting results between the PCA and EF can be attributed to the background values used, indicating that background values must be selected carefully. 相似文献
49.
The study on the performance of a fluorinated polyaniline (PANI) as a fiber coating for solid-phase microextraction (SPME) had been reported and 16 polycyclic aromatic hydrocarbons (PAHs) were selected to evaluate the performance of this fiber. Various parameters including sample volume, extraction temperature, time of desorption and extraction, pH and ionic strength were investigated intensively. A direct comparison between PANI-SPME fiber and commercial fiber was conducted. The results showed that the PANI-SPME coating had high affinity towards target compounds and the proposed method was successfully applied for the detection of real samples: rainfall and Taihu Lake water collected from Southern China. The whole PANI-SPME-GC method offers acceptable accuracy, precision and sensitivity and low detection limits, which is applicable to monitor trace levels of PAHs in real water bodies. 相似文献
50.
Extracellular polymeric substances (EPS) were extracted from Aspergillus fumigatus using cationic exchange resin technique. The EPS were mainly composed of polysaccharide and low quantities of protein and nucleic acid. Biosorption of Cd(II), Pb(II), and Cu(II) of EPS was investigated as a function of pH using differential pulse polarography and the Ruzic model. Results showed that the EPS biosorption capacity determined using either the direct titration curves i?=?f(C M) or the method proposed by Ruzic (Analytica Chimica Acta 140:99–113, 1982) were coincident. Cu(II) had the highest affinity with EPS followed by Pb(II) and Cd(II). The total number of binding sites for Cu(II) and Cd(II) increased with pH in the range of 4.0–7.0. Similar trend was observed for Pb(II) at pH?4.0–5.0, while precipitates were observed at pH?6.0 and 7.0. The conditional binding constants of these three metals displayed low levels of fluctuation with pH and ranged from 4.02?±?0.02 to 5.54?±?0.05. 相似文献