Recently, studies on the degradation of emerging pollutants by activated persulfate (PS) have been widely reported. As a classic process, heat-activated peroxydisulfate (PDS) has been extensively used in practical engineering. However, the establishment of the quantitative relationship between the reduction of pollutants and PDS and the kinetic model of the heat-activated PDS process are rarely reported. In this study, triazine herbicide simazine (SMZ), which is frequently found in the environment, was selected as the target pollutant, and a series of coherent studies including kinetics calculation, radicals identification, and product analysis provided the basis for the establishment of the model. The steady-state model and unsteady-state model initially described the process of heat-activated PDS and degradation effect on SMZ. It was found that in the process of heat/PDS, the degradation of SMZ was significantly related to the decomposition of PDS. The decomposition of each unit of PDS at the beginning of the reaction could lead to the degradation of 1.616 units of SMZ. In addition, during the reaction, sulfate radical (SO₄^•−) was the dominant radical and could be partly transformed to hydroxyl radical (^•OH) to participate in the reaction (with the ratio of 25:1). Finally, it was noted that the reaction intermediates could not be ignored in the establishment of the unsteady-state model. This study provides a set of coherent research methods, which is conducive to further simulation of the heat-activated PDS process.

最近，关于活性过硫酸盐 (PS) 降解新兴污染物的研究已被广泛报道。作为经典工艺，热活化过二硫酸盐 (PDS) 已广泛应用于实际工程中。然而，关于污染物的减少与PDS之间的定量关系的建立以及热活化PDS过程的动力学模型的建立鲜有报道。本研究以环境中常见的三嗪类除草剂西玛津（SMZ）为目标污染物，通过动力学计算、自由基鉴定、产物分析等一系列相关研究为建立模型。稳态模型和非稳态模型初步描述了热激活 PDS 的过程和对 SMZ 的降解效应。发现在加热/PDS过程中，SMZ的降解与PDS的分解显着相关。反应开始时每个单元的 PDS 分解可导致 1.616 个单元的 SMZ 降解。此外，在反应过程中，硫酸根（SO₄ ^•- ) 是主要自由基，可以部分转化为羟基自由基( ^• OH) 参与反应（比例为25:1）。最后，指出在建立非稳态模型时不能忽略反应中间体。本研究提供了一套连贯的研究方法，有利于进一步模拟热活化PDS过程。