這些結(jié)果揭示了SGFW處理過程中臭氧的選擇性氧化和?OH的非選擇性氧化，為SGFW處理方法的選擇提供了理論支持。

1. 文章信息

標(biāo)題：Molecular comparison of organic matter removal from shale gas flowback wastewater: Ozonation versus Fenton process

中文標(biāo)題：頁巖氣返排廢水中有機物去除的分子比較：臭氧與芬頓法

2. 文章鏈接

https://doi.org/10.1016/j.scitotenv.2023.167147

3. 期刊信息

期刊名：Science of The Total Environment Volume 905, 20 December 2023, 167147

4. 作者信息：Xinglong Chen, Guonan Zhao, Zhuowen Yang, Qibin Li

Faculty of Geosciences and Environmental Engineering, Southwest Jiaotong University, 611756, China

5.文中所用產(chǎn)品型號：3S-J5000

重點

?研究了臭氧氧化和芬頓法處理SGFW的DOM組成。

?臭氧氧化和芬頓工藝對SGFW DOM的影響存在顯著差異。

?比較了臭氧氧化和芬頓法的降解機理。

摘要

頁巖氣開采過程中會產(chǎn)生大量含有難降解有機物的頁巖氣返排廢水，如果處理不當(dāng)，會對環(huán)境造成嚴(yán)重威脅。然而，SGFW中極其復(fù)雜的有機物組成尚不清楚，它們在O3-和?oh主導(dǎo)體系中的轉(zhuǎn)化途徑也不清楚，這制約了處理工藝的選擇和操作參數(shù)的優(yōu)化。采用電噴霧電離傅立葉變換離子回旋共振質(zhì)譜法比較研究了臭氧法和Fenton法處理SGFW中溶解性有機物（DOM）的去除特性和反應(yīng)機理。結(jié)果表明，兩種工藝均能降解低氧高不飽和酚類有機物、多酚類化合物和多環(huán)芳烴，并將其轉(zhuǎn)化為脂肪類有機物和高氧高不飽和酚類有機物。隨著活性氧（臭氧氧化作用為O3， Fenton氧化作用為?OH）作用的增加，臭氧氧化過程中降解產(chǎn)物（主要是脂肪族有機物）增加。而在Fenton工藝中，更大范圍的DOM被去除，沒有脂肪族有機物的積累。臭氧化和Fenton法降解DOM的主要途徑是氧加成反應(yīng)（+ 30、+H2O2和+2O）。臭氧化反應(yīng)表現(xiàn)為更劇烈的氧合、羥化和羧化反應(yīng)，F(xiàn)enton法表現(xiàn)為更劇烈的斷鏈反應(yīng)。這些結(jié)果揭示了SGFW處理過程中臭氧的選擇性氧化和?OH的非選擇性氧化，為SGFW處理方法的選擇提供了理論支持。

Shale gas extraction process generates a large amount of shale gas flowback wastewater (SGFW) containing refractory organic compounds, which can pose serious environmental threats if not properly treated. However, the extremely complex compositions of organics in SGFW are still unknown and their transformation pathways in O3- and ?OH-dominated systems are not well recognized, which restrain the selection of treatment technology and optimization of operational parameters. The removal characteristics and reaction mechanism of dissolved organic matter (DOM) in SGFW treated by ozonation and Fenton processes were comparatively investigated using electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry. The results showed that both processes could degrade low-oxygen highly unsaturated and phenolic organics, polyphenolics and polycyclic aromatics, and transform them into aliphatic organics and high-oxygen highly unsaturated and phenolic organics. With increasing action of reactive oxygen species (O3 for ozonation and ?OH for Fenton process), the degradation products (mainly aliphatic organics) increased during ozonation. However, in Fenton process, a wider range of DOM was removed without aliphatic organics accumulation. The degradation mechanisms of DOM during ozonation and Fenton processes included oxygen addition reactions (+3O, +H2O2, and +2O) as dominant pathways. However, ozonation showed more violent oxygenation, hydroxylation, and carboxylation, while Fenton process presented more violent chain-breaking reactions. These results revealed the selective oxidation of ozone and nonselective oxidation of ?OH during SGFW treatment, and provided theoretical support for selecting SGFW treatment approaches.