High concentration N-methyldiethanolamine (MDEA)-containing wastewater with strong alkaline, high chemical oxygen demand (COD), and toxic organics, cannot be directly treated by biochemical process. In this paper, effect of operation parameters (temperature, reaction pressure and residence time) on removal ratio of COD and MDEA was investigated by catalytic wet air oxidation (CWAO) over commercial activated carbon (AC). The degradation pathway of MDEA in the CWAO was proposed. The results showed that the concentration of MDEA, COD, total organic carbon (TOC), and total nitrogen (TN) were 18.92, 61.2, 21.34 and 5.65 g·L⁻¹, respectively. The contribution rate of MDEA concentration to COD in the wastewater reached up to 89.8%. The removal ratio of MDEA and COD exceeded 98% and ∼90% at temperature of 230 °C, reaction pressure of 5.0 MPa and residence time of 90 min for 168 h continuous running, respectively. The surface carboxylic acid groups of AC played a key role in the formation of hydroxyl radicals (·OH), due to the O₂ was adsorbed by the carboxyl groups on the surface of AC to form ·OH, and the ·OH then attacked the CN bond of the MDEA to generate other intermediate products, and then these intermediate products was further oxidized to NH₄⁺, CO₂ and H₂O. This work provides a promising pretreatment technology of high concentration MDEA-containing wastewater.

高浓度含N-甲基二乙醇胺（MDEA）的废水具有强碱性、高化学需氧量（COD）和有毒有机物，不能直接用生化工艺处理。在本文中，通过催化湿空气氧化 (CWAO) 在商业活性炭 (AC) 上研究操作参数（温度、反应压力和停留时间）对 COD 和 MDEA 去除率的影响。提出了MDEA在CWAO中的降解途径。结果表明，MDEA、COD、总有机碳（TOC）和总氮（TN）的浓度分别为18.92、61.2、21.34和5.65 g·L ^-1， 分别。MDEA浓度对废水中COD的贡献率高达89.8%。MDEA 和 COD 的去除率在 230 ℃、5.0 MPa 的反应压力和 90 分钟的停留时间下分别超过 98% 和 90%，连续运行 168 小时。AC的表面羧酸基团在羟基自由基（·OH）的形成中起关键作用，因为O ₂被AC表面的羧基吸附形成·OH，然后·OH攻击羟基自由基ç的MDEA，以产生其他中间产品，然后将这些中间产物的N键被进一步氧化成NH ₄ ⁺，CO ₂和H ₂O. 这项工作为高浓度含 MDEA 废水的预处理提供了一种很有前景的技术。