Ti4O7/Ti电极电催化氧化法处理铝合金化铣清洗废液

Electrocatalytic Oxidation of Aluminum Alloy Chemical Milling Wastewater Using Ti4O7/Ti Electrode

摘要:

铝合金化学铣切过程产生的清洗废液具有高碱度和富含有机物的特性，常规的生化处理方法难以有效处理，直接排放会对环境造成严重危害。采用电催化氧化法处理铝合金化铣清洗废液，以亚氧化钛涂层的钛电极作为阳极、不锈钢作为阴极，研究了化铣清洗废液中的典型有机物在Ti₄O₇/Ti电极表面的氧化和降解机制及电解工艺参数（如初始pH、电流密度、搅拌方式、污染物初始浓度及处理时间等）对清洗液COD_Cr去除率的影响。结果表明：铝合金化铣清洗废水中的三乙醇胺无法在Ti₄O₇/Ti电极表面直接氧化，其降解机制为Ti₄O₇/Ti电极表面产生·OH对其间接氧化；采用曝气搅拌方式，在溶液pH=7、电流密度5 mA?cm^-2优化条件下，处理后的铝合金化铣清洗废液的COD_Cr由初始5 210 mg?L^-1降至42 mg?L^-1，低于300 mg?L^-1环保排放标准。因此，以Ti₄O₇/Ti为阳极的电催化氧化法可有效地处理铝合金化铣清洗废液，使其达到环保排放标准。本研究为含醇胺类有机废水的处理提供可靠的理论和技术支持，在降低企业生产成本、改善人类生存环境等方面具有重要理论和实际意义。

Abstract:

The cleaning water generated during the chemical milling of aluminum alloys exhibits high alkalinity and organic-rich compounds， posing challenges for conventional biochemical methods. Direct discharge may cause severe environmental harm. This study employs electrocatalytic oxidation to treat wastewater from chemical milling of aluminum alloy. Using a titanium suboxide coated electrode and stainless steel as the cathode， this study investigates the oxidation and degradation mechanisms of typical organic compounds in the chemical milling wastewater on the Ti₄O₇/Ti electrode surface. In addition， this study explores the effects of electrolysis process parameters such as initial pH， current density， stirring method， initial pollutant concentration， and treatment time on the COD_Cr removal rate of the wastewater. The results indicate that triethanolamine in the cleaning wastewater of the chemical milling of aluminum alloy cannot be directly oxidized on the Ti₄O₇/Ti electrode surface. Under optimized conditions， the COD_Cr of the treated aluminum alloy chemical milling wastewater decreases from the initial 5 210 mg?L^-1 to 42 mg?L^-1， meeting the environmental discharge standard of 300 mg?L^-1. The optimal treatment conditions are： pH=7， 5 mA?cm^-2， and aeration stirring. Therefore， electrocatalytic oxidation with Ti₄O₇/Ti as the anode proves effective in treating wastewater from aluminum alloy chemical milling， bringing it into compliance with environmental discharge standards.