Shen Wensheng, Liu Xiangrong, Shi Chen, Yang Jie, Zhao Shunsheng, Yang Zaiwen, Wang Dan
College of Chemistry and Chemical Engineering, Xi'an University of Science and Technology, Xi'an 710054, China.
State Key Laboratory of Green and Low-Carbon Development of Tar-Rich Coal in Western China, Xi'an University of Science and Technology, Xi'an 710021, China.
Microorganisms. 2023 Sep 26;11(10):2397. doi: 10.3390/microorganisms11102397.
The biodegradation of tar-rich coal in the Ordos Basin was carried out by () under actions of four kinds of surfactants, namely, a biological surfactant (Rh), a nonionic surfactant (Triton X-100), an anionic surfactant (LAS), and a cationic surfactant (DTAB). The biodegradation rates under the actions of Triton X-100, LAS, Rh, DTAB, and the control group (without surfactant) were 59.8%, 54.3%, 51.6%, 17.3%, and 43.5%, respectively. The biodegradation mechanism was studied by examining the influences of surfactants on coal samples, bacteria, and degradation products in the degradation process. The results demonstrated that Rh, Triton X-100, and LAS could promote bacterial growth, while DTAB had the opposite effect. Four surfactants all increased the cell surface hydrophobicity (CSH) of , and Triton X-100 demonstrated the most significant promotion of CSH. The order of improvement in microbial cell permeability by surfactants was DTAB > TritonX-100 > LAS > Rh > control group. In the presence of four surfactants, Triton X-100 exhibited the best hydrophilicity improvement for oxidized coal. Overall, among the four surfactants, Triton X-100 ranked first in enhancing the CSH of bacteria and the hydrophilicity of oxidized coal and second in improving microbial cell permeability; thus, Triton X-100 was the most suitable surfactant for promoting 's biodegradation of tar-rich coal. The GC-MS showed that, after the action of Triton X-100, the amount of the identified degradation compounds in the toluene extract of the liquid product decreased by 16 compared to the control group, the amount of dichloromethane extract decreased by 6, and the amount of ethyl acetate extract increased by 6. Simultaneously, the contents of alkanes in the extracts of toluene and dichloromethane decreased, lipids increased, and ethyl acetate extract exhibited little change. The FTIR analysis of the coal sample suggested that, under the action of Triton X-100, compared to oxidized coal, the and (CH)/(CH) of the remaining coal decreased by 0.07 and 1.38, respectively, indicating that Triton X-100 enhanced the degradation of aromatic and aliphatic structures of oxidized coal. Therefore, adding a suitable surfactant can promote the biodegradation of tar-rich coal and enrich its degradation product.
鄂尔多斯盆地富焦油煤的生物降解是在四种表面活性剂的作用下由（）进行的，这四种表面活性剂分别是一种生物表面活性剂（Rh）、一种非离子表面活性剂（吐温X-100）、一种阴离子表面活性剂（直链烷基苯磺酸钠）和一种阳离子表面活性剂（十六烷基三甲基溴化铵）。吐温X-100、直链烷基苯磺酸钠、Rh、十六烷基三甲基溴化铵作用下以及对照组（无表面活性剂）的生物降解率分别为59.8%、54.3%、51.6%、17.3%和43.5%。通过考察表面活性剂在降解过程中对煤样、细菌和降解产物的影响来研究生物降解机理。结果表明，Rh、吐温X-100和直链烷基苯磺酸钠可促进细菌生长，而十六烷基三甲基溴化铵则有相反作用。四种表面活性剂均提高了（）的细胞表面疏水性（CSH），吐温X-100对CSH的促进作用最为显著。表面活性剂改善微生物细胞通透性的顺序为十六烷基三甲基溴化铵＞吐温X-100＞直链烷基苯磺酸钠＞Rh＞对照组。在四种表面活性剂存在的情况下，吐温X-100对氧化煤的亲水性改善效果最佳。总体而言，在这四种表面活性剂中，吐温X-100在增强细菌CSH和氧化煤亲水性方面排名第一，在改善微生物细胞通透性方面排名第二；因此，吐温X-100是促进（）对富焦油煤生物降解的最合适表面活性剂。气相色谱-质谱联用仪（GC-MS）分析表明，吐温X-100作用后，液体产物甲苯提取物中已鉴定的降解化合物数量比对照组减少了16种，二氯甲烷提取物减少了6种，乙酸乙酯提取物增加了6种。同时，甲苯和二氯甲烷提取物中的烷烃含量降低，脂质含量增加，乙酸乙酯提取物变化不大。煤样的傅里叶变换红外光谱（FTIR）分析表明，在吐温X-100作用下，与氧化煤相比，剩余煤的（）和（CH）/（CH）分别降低了0.07和1.38，表明吐温X-100增强了氧化煤芳烃和脂肪族结构的降解。因此，添加合适的表面活性剂可促进富焦油煤的生物降解并富集其降解产物。
