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51.
A weak aspect of the electro-Fenton (EF) oxidation of contaminants is the dependence of the Fenton reaction on acidic pH values. Therefore, the rationale of this work was to develop a novel catalyst capable of promoting the EF oxidation process at near-neutral and basic pH values. In this framework, rhombohedral FeCO3 was synthesized hydrothermally and used as a catalyst in the EF oxidation of p-benzoquinone (BQ). The catalyst was characterized using various surface and spectroscopic methods. Moreover, the effects of applied current (100–500 mA), time (1–9 h), catalyst dosage (0.25–1.00 g L−1), and initial concentration of BQ (0.50–1.00 mM) on the total organic carbon removal efficiency were determined. The results indicated that a 400 mA current was sufficient for a 95% total organic carbon removal and that the increase in catalyst dosage had a positive effect on the mineralization of BQ. It was determined that at pH 3, FeCO3 behaved like a homogeneous catalyst by releasing Fe3+ ions; whereas, at the pH range of 5–7, it shifted to a homogeneous/heterogeneous catalyst. At pH 9, it worked solely as a heterogeneous catalyst due to the decrease of Fe ions passing into the solution. Finally, the spent catalyst did not undergo structural deformations after the EF treatment at higher pH values and could be regenerated and used several times  相似文献   
52.
为确定金华市城市污水处理厂污泥资源化利用途径,对金华市某污水处理厂的脱水污泥进行了采样和成分分析.结果表明,所有污泥为中性,pH 6.89,含水率较高75%;污泥中有机质、氮、磷、钾含量丰富;污泥中重金属的含量较低,均符合国家农用污泥中污染物控制标准.以此为基础对污泥的农用价值及其应用前景作了分析和展望.  相似文献   
53.
A new, simple and sensitive method for isolating nine compounds from the bisphenol group (analogues: A, B, C, E, F, G, Cl2, Z, AP) based on one-step liquid–liquid microextraction with in situ acylation followed by gas chromatography-mass spectrometry was developed and validated using influent and effluent wastewaters. The chemometric approach based on the Taguchi method was used to optimize the main conditions of simultaneous extraction and derivatization. The recoveries of the proposed procedure ranged from 85 to 122%, and the repeatability expressed by the coefficient of variation did not exceed 8%. The method’s limits of detection were in the range of 0.4–64 ng/L, and the method’s limits of quantification ranged from 1.3 to 194 ng/L. The developed method was used to determine the presence of the tested compounds in wastewater from a municipal wastewater treatment plant located in northeastern Poland. From this sample, eight analytes were detected. Concentrations of bisphenol A of 400 ng/L in influent and 100 ng/L in effluent were recorded, whereas other bisphenols reached 67 and 50 ng/L for influent and effluent, respectively. The removal efficiency of bisphenol analogues in the tested wastewater treatment plant ranged from 7 to approximately 88%.  相似文献   
54.
芬顿试剂氧化污水及无机离子影响的研究   总被引:5,自引:0,他引:5  
采用芬顿试剂对生活污水进行预氧化处理,通过测定COD、BOD5变化来比较氧化效果.在单因素实验的基础上,采用正交实验研究.芬顿试剂的最佳氧化工艺是:FeSO4.7H2O物质的量为3mmol,pH值为3,n(H2O2)∶n(Fe^2+)为3∶1;反应时间为120 min.处理后的废水的可生化性、COD去除率大大提高,为进一步的生化处理创造了良好的条件;研究了几种无机离子对芬顿试剂氧化的促进或抑制作用.研究表明,Fe3+具有一定的促进作用,而Cu^2+、Cl^-有一定的抑制作用,H2PO4-有较强的抑制作用.  相似文献   
55.
We investigated how different doses of microwave irradiation (MR) affect seed germination in Sorghum, including the level of remediation against textile and surgical wastewater (WW) by modulating biochemical and morpho-physiological mechanisms under glutamic acid (GA) application. The experiment was conducted to determine the impact of foliar-applied GA on Sorghum under wastewater conditions. Plants were treated with or without microwave irradiation (30 s, 2.45 GHz), GA (5 and 10 mM), and wastewater (0, 25, 50, and 100). Growth and photosynthetic pigments were significantly decreased in plants only treated with various concentrations of WW. GA significantly improved the plant growth characteristics both in MR-treated and -untreated plants compared with respective controls. HMs stress increased electrolyte leakage (EL), hydrogen peroxide (H2O2), and malondialdehyde (MDA) content; however, the GA chelation significantly improved the antioxidant enzymes activities such as ascorbate oxidase (APX), superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) both in MR-treated and -untreated plants under WW stress compared with respective controls. The results suggested that the MR-treated plants accumulate higher levels of HMs under GA addition in comparison to the WW-only-treated and MR-untreated plants. The maximum increase in Cd accumulation was observed in the range of 14–629% in the roots, 15–2964% in the stems, and 26–4020% in the leaves; the accumulation of Cu was 18–2757% in the roots, 15–4506% in the stems, and 23–4605% in the leaves; and the accumulation of Pb was 13–4122% in the roots, 21–3588% in the stems, and 21–4990% in the leaves under 10 mM GA and MR-treated plants. These findings confirmed that MR-treated sorghum plants had a higher capacity for HMs uptake under GA and could be used as a potential candidate for wastewater treatment.  相似文献   
56.
金刚石薄膜电极处理含氯酚废水的实验研究   总被引:1,自引:0,他引:1  
以硼掺杂金刚石薄膜(BDD)为电极,采用电化学氧化的方法对含氯酚废水进行实验研究。采用循环流动的方式,结果表明:在给定不同恒电位的情况下,电流随时间变化的规律也不同;在高电位时电流密度比较大,使间接氧化增强,导致COD去除率和瞬时电流效率(ICE)增大;由于支持电解质N aC l在电解过程中产生的次氯酸盐氧化性强,因此N aC l比H2SO4对COD去除率和ICE增大更有利。采用钛基活性涂层(ACT)电极与金刚石电极的对比实验发现:由于BDD电极的弱吸附性,其处理效果明显优于ACT。  相似文献   
57.
以高炉瓦斯灰为主要原料、粘土和硅酸钠作为添加剂制备曝气生物滤池填料.通过正交试验得出高炉瓦斯灰曝气生物滤池填料的最佳制备工艺条件为:高炉瓦斯灰、粘土、硅酸钠质量分数分别为79%,15%,6%,烧制温度为600℃. 该曝气生物滤池填料具有密度较小、强度较大、比表面较大等特点,将其应用于曝气生物滤池处理酱油废水,在水力停留时间为4h、气水比6∶1、滤层高度为100cm的情况下,COD的去除率达到70.3%,NH3-N的去除率达到74%,色度的去除率达到60%,取得了较好的处理效果. 利用高炉瓦斯灰制备曝气生物滤池填料,为高炉瓦斯灰的资源化利用探索了一条新途径.  相似文献   
58.
基于对山西晋煤集团赵庄煤矿矿井水处理厂原处理系统设计参数存在不足的分析,根据赵庄煤矿的现状,确定采用新型旋流澄清净水装置+过滤+超滤等工艺。本工艺使用后,处理水量由原来的6000m3/d提高到12000m3/d;SS去除率由原来的65%提高到90%以上,基本解决了目前赵庄煤矿矿井水处理厂处理能力不足的问题。  相似文献   
59.
酚降解性活性污泥的固定化研究   总被引:2,自引:1,他引:2  
实验确定了以聚乙烯醇(PVA)为包埋剂固定化活性污泥的最佳条件,制备得到了固定化降解苯酚的活性污泥.最佳条件为:PVA质量浓度为100 g/L,交联剂pH值为7.0.固定化后活性污泥性能得到明显改善,缩短或消除了活性污泥降解苯酚的延滞期,可在较短时间内达到高降解率,对于质量浓度为1 500g/L的含酚废水,前5日的降解率可达98.3%.  相似文献   
60.
从废弃烟梗固态发酵物中筛选出一株酵母菌,根据培养、形态和生理生化特征初步鉴定为深红酵母(Rhodotorula rubra),标记为JLC.JLC在烟草废水中生长良好,5%接种量,28℃培养4 d,细胞干重为9.37 g/L.添加0.8%的NaH2PO4,可使细胞干重达到14.87 g/L.JLC产类胡萝卜素,其色素最大吸收波长在485 nm,初步实验条件下最大色素产量为3.04 mg/L.  相似文献   
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