Yue Rengyu, Ye Zhibin, Gao Sichen, Cao Yiqi, Lee Kenneth, An Chunjiang, Qu Zhaonian, Wan Shuyan
Department of Building, Civil and Environmental Engineering, Concordia University, Montreal, QC H3G 1M8, Canada.
Department of Chemical and Materials Engineering, Concordia University, Montreal, QC H3G 1M8, Canada.
Sci Total Environ. 2023 May 15;873:162363. doi: 10.1016/j.scitotenv.2023.162363. Epub 2023 Feb 23.
The produced effluents after shoreline washing contain a certain number of oil droplets and further treatment is necessary. In this study, the innocuous, widely available, and biodegradable sodium caseinate (NaCas) was deployed to capture oil pollutants from oily wastewater. Oil droplets can be effectively and rapidly captured by NaCas and subsequently removed after pH-triggered separation, producing a clean supernatant with low turbidity. The removal efficiency was enhanced by increasing NaCas concentration and separation time. The salinity inhibited the oil removal by increasing the interfacial tension of NaCas and reducing their sorption sites caused by the large particle size. Humic acid negatively influenced the oil separation performance of NaCas because of the competitive sorption and enhanced repulsion force between oil and NaCas. In addition, the increasing temperature was found to augment the oil removal. Factorial analysis revealed the individual factors and two-factor interactions that had significant effects on oil removal. Biotoxicity experiments proved that NaCas can fully offset the inhibitory effect of oil on the photosynthesis of algae and thus promote algae growth. Two post-treatment methods, namely thermal treatment, and biodegradation, can be used for the post-treatment of NaCas/oil precipitation residues. The use of NaCas-assisted responsive separation in the treatment of washing effluents can help achieve a sustainable shoreline oil spill response.
海岸线冲洗后产生的废水含有一定数量的油滴，因此需要进一步处理。在本研究中，使用了无毒、广泛可得且可生物降解的酪蛋白酸钠（NaCas）来捕获含油废水中的油污染物。油滴能够被NaCas有效且快速地捕获，随后在pH触发分离后被去除，从而产生低浊度的清澈上清液。通过增加NaCas浓度和分离时间，去除效率得以提高。盐度通过增加NaCas的界面张力并减少由大粒径导致的吸附位点来抑制除油效果。腐殖酸由于竞争性吸附以及油与NaCas之间排斥力增强，对NaCas的油分离性能产生负面影响。此外，发现温度升高会增强除油效果。因子分析揭示了对除油有显著影响的各个因素以及双因素相互作用。生物毒性实验证明，NaCas能够完全抵消油对藻类光合作用的抑制作用，从而促进藻类生长。两种后处理方法，即热处理和生物降解，可用于NaCas/油沉淀残渣的后处理。在洗涤废水处理中使用NaCas辅助的响应分离有助于实现可持续的海岸线溢油应对。
