Persulfate has the advantages of good stability, good water solubility, strong oxidation and friendly reaction products, which can make up for the shortcomings of other oxidants. The excessive decomposition of persulfate can produce a new active substance, sulfate free radical. There is a pair of lone pair electrons in SO4, whose oxidation ability is higher than that of persulfate itself, which is close to the half-life of hydroxyl radical SO4 (4s, 40 C), so that it can be more fully exposed to pollutants. Persulfate activation also produces OH, which oxidizes more refractory substances, such as polychlorinated biphenyls. Sodium persulfate usually exists in the form of ammonium salt, potassium salt and sodium salt, while sodium persulfate is often used in in-situ chemical oxidation technology.

　　过硫酸钠(Na2S2O8也称为过硫酸钠。白色结晶或结晶性粉末。无味。无味的。分子量238.13。常温下逐渐分解，加热或在乙醇中可迅速分解，分解氧气而形成焦硫酸钠。水分与铂黑、银、铅、铁、铜、镁、镍、锰等金属离子或其合金能促进分解，高温(约200℃)快速分解，释放过氧化氢。溶于水(20℃70.4)。长时间与皮肤接触，可引起过敏，操作时应注意。大鼠经口LD50895mg/kg。

　　Sodium persulfate (Na2S2O8 is also called sodium persulfate). White crystalline or crystalline powder. Tasteless. Tasteless. Molecular weight 238.13. It decomposes gradually at room temperature, decomposes rapidly in heating or ethanol, and decomposes oxygen to form sodium pyrosulfate. Water and platinum black, silver, lead, iron, copper, magnesium, nickel, manganese and other metal ions or their alloys can promote decomposition, rapid decomposition at high temperature (about 200 C), release hydrogen peroxide. It is soluble in water (20 70.4). Long time contact with skin can cause allergy. Attention should be paid to the operation. LD50895 mg/kg via oral cavity in rats.

　　化学性质

　　Chemical property

　　过硫酸钠是一种稳定的强氧化剂。过硫酸盐活化产生自由基对去除石油污染物具有重要意义。过硫酸在碱、金属离子、金属矿物、热、有机化合物等条件下均能产生自由基，其活化机理也不尽相同。

　　Sodium persulfate is a stable strong oxidant. The production of free radicals by persulfate activation is of great significance to the removal of petroleum pollutants. Persulfuric acid can produce free radicals under the conditions of alkali, metal ions, metal minerals, heat and organic compounds, and its activation mechanism is also different.

　　过硫酸盐激进的化学

　　Radical chemistry of persulfate

　　它有一对孤立的电子，具有很强的电子生成能力和较高的氧化能力。理论上，大多数有机污染物可以氧化成小分子有机酸，终矿化成CO2和H2O。许多学者研究了SO与有机化合物反应的产物及其机理。目前，围绕特定污染物的研究，逐渐形成了电子转移、氢提取和加成三个基本观点。

　　It has a pair of isolated electrons, and has a strong ability of electron generation and oxidation. In theory, most organic pollutants can be oxidized to small molecular organic acids, and eventually mineralized to CO2 and H2. Many scholars have studied the products and mechanism of the reaction of SO with organic compounds. At present, three basic viewpoints, namely, electron transfer, hydrogen extraction and addition, have been gradually formed around the study of specific pollutants.

　　1)电子转移

　　1) Electron transfer

　　与芳香族化合物的反应主要是通过电子转移进行的。亲电子基团也是如此，它在氧化过程中从有机分子中窃取电子。研究表明，有机分子中含有氨基(-nh2)、羟基(-oh)或烷氧基(-or)等供电子基团时，氧化反应速率加快;相反，有机分子中存在电子捕获基团硝基(-no2)和羰基(C=O)，这将减慢氧化反应的速率。

　　Reactions with aromatic compounds are mainly carried out by electron transfer. The same is true for electrophilic groups, which steal electrons from organic molecules during oxidation. The results show that the rate of oxidation is accelerated when the organic molecule contains amino (-nh2), hydroxyl (-oh) or alkoxy (-or) donor groups. On the contrary, there are electron capture groups nitro (-no2) and carbonyl (C=O) in the organic molecule, which will slow down the rate of oxidation.