Abstract:
Municipal wastewater treatment systems use the chemical oxygen demand test (COD) to identify organic contaminants in industrial effluents that impede treatment due to their high concentration. This study reduced the COD levels in tannery wastewater using a multistage treatment process that included Fenton oxidation, chemical coagulation, and nanotechnology based on a synthetic soluble COD standard solution. At an acidic pH of 5, Fenton oxidation reduces the COD concentration by approximately 79%. It achieves this by combining 10 mL/L of H2O2 and 0.1 g/L of FeCl2. Furthermore, the author selected the FeCl3 coagulant for the coagulation process based on the best results of comparisons between different coagulants. At pH 8.5, the coagulation dose of 0.15 g/L achieved the maximum COD removal efficiency of approximately 56.7%. Finally, nano bimetallic Fe/Cu was used to complete the degradation and adsorption of the remaining organic pollutants. The XRD, SEM, and EDX analyses proved the formation of Fe/Cu nanoparticles. A dose of 0.09 g/L Fe/Cu NPs, 30 min of contact time, and a stirring rate of 200 rpm achieve a maximum removal efficiency of about 93% of COD at pH 7.5. The kinetics studies were analyzed using pseudo-first-order P.F.O., pseudo-second-order P.S.O., and intraparticle diffusion models. The P.S.O. showed the best fit among the kinetic models, with an R2 of 0.998. Finally, the authors recommended that technique for highly contaminated industrial effluents treatment for agriculture or industrial purposes.
摘要:
市政污水处理系统使用化学需氧量测试(COD)来识别工业废水中由于高浓度而阻碍处理的有机污染物。本研究使用包括Fenton氧化在内的多阶段处理工艺降低了制革废水中的COD水平,化学混凝,和基于合成可溶性COD标准溶液的纳米技术。在酸性pH为5时,Fenton氧化使COD浓度降低约79%。它通过组合10mL/L的H2O2和0.1g/L的FeCl2来实现这一点。此外,作者根据不同混凝剂之间的比较,选择了FeCl3混凝剂用于混凝过程。在pH8.5时,0.15g/L的混凝剂量实现了约56.7%的最大COD去除效率。最后,纳米双金属Fe/Cu完成了对残留有机污染物的降解和吸附。XRD,SEM,和EDX分析证明了Fe/Cu纳米颗粒的形成。0.09g/LFe/CuNPs的剂量,接触时间30分钟,和200rpm的搅拌速率在pH7.5下实现约93%的COD的最大去除效率。使用伪一级P.F.O.分析了动力学研究,伪二阶P.S.O.,和粒子内扩散模型。P.S.O.在动力学模型中表现出最佳拟合,R2为0.998。最后,作者建议将该技术用于农业或工业用途的高度污染的工业废水处理。