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.

　　過(guò)硫酸鈉(Na2S2O8也稱為過(guò)硫酸鈉。白色結(jié)晶或結(jié)晶性粉末。無(wú)味。無(wú)味的。分子量238.13。常溫下逐漸分解，加熱或在乙醇中可迅速分解，分解氧氣而形成焦硫酸鈉。水分與鉑黑、銀、鉛、鐵、銅、鎂、鎳、錳等金屬離子或其合金能促進(jìn)分解，高溫(約200℃)快速分解，釋放過(guò)氧化氫。溶于水(20℃70.4)。長(zhǎng)時(shí)間與皮膚接觸，可引起過(guò)敏，操作時(shí)應(yīng)注意。大鼠經(jīng)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.

　　化學(xué)性質(zhì)

　　Chemical property

　　過(guò)硫酸鈉是一種穩(wěn)定的強(qiáng)氧化劑。過(guò)硫酸鹽活化產(chǎn)生自由基對(duì)去除石油污染物具有重要意義。過(guò)硫酸在堿、金屬離子、金屬礦物、熱、有機(jī)化合物等條件下均能產(chǎn)生自由基，其活化機(jī)理也不盡相同。

　　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.

　　過(guò)硫酸鹽激進(jìn)的化學(xué)

　　Radical chemistry of persulfate

　　它有一對(duì)孤立的電子，具有很強(qiáng)的電子生成能力和較高的氧化能力。理論上，大多數(shù)有機(jī)污染物可以氧化成小分子有機(jī)酸，終礦化成CO2和H2O。許多學(xué)者研究了SO與有機(jī)化合物反應(yīng)的產(chǎn)物及其機(jī)理。目前，圍繞特定污染物的研究，逐漸形成了電子轉(zhuǎn)移、氫提取和加成三個(gè)基本觀點(diǎn)。

　　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)電子轉(zhuǎn)移

　　1) Electron transfer

　　與芳香族化合物的反應(yīng)主要是通過(guò)電子轉(zhuǎn)移進(jìn)行的。親電子基團(tuán)也是如此，它在氧化過(guò)程中從有機(jī)分子中竊取電子。研究表明，有機(jī)分子中含有氨基(-nh2)、羥基(-oh)或烷氧基(-or)等供電子基團(tuán)時(shí)，氧化反應(yīng)速率加快;相反，有機(jī)分子中存在電子捕獲基團(tuán)硝基(-no2)和羰基(C=O)，這將減慢氧化反應(yīng)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.