Laboratory of Environmental Technology, INET, Tsinghua University, Beijing 100084, PR China; Beijing Key Laboratory of Radioactive Wastes Treatment, Tsinghua University, Beijing 100084, PR China.
Laboratory of Environmental Technology, INET, Tsinghua University, Beijing 100084, PR China.
J Hazard Mater. 2022 Jul 5;433:128727. doi: 10.1016/j.jhazmat.2022.128727. Epub 2022 Mar 19.
Saline chemical wastewater containing ammonia and toxic organic pollutants has been a challenge for conventional wastewater treatment technology. Advanced treatment is thus required. In this study, the removal of ammonia and phenol in saline chemical wastewater by radiation was investigated in detail. The results showed that chloridion in saline chemical wastewater could be transferred to •Cl and •ClO by radiation, which promoted ammonia oxidation, but inhibited phenol degradation. Solution pH affected the types of reactive species, which further affected the removal of ammonia and phenol. When ammonia and phenol co-existed in saline chemical wastewater, the removal efficiency of ammonia was depressed compared to that in the absence of phenol. Similarly, the phenol removal efficiency was also depressed in the presence of ammonia when the solution pH was lower than 7.0. Interestingly, the phenol removal efficiency was improved with increase of either chloridion concentration (2-8 g/L) or dose (2-5 kGy), which was attributed to the formation of intermediate nitrogen-centered radicals that can react with phenol. In addition, the intermediate products of phenol degradation under different conditions were identified. The acute toxicity of saline chemical wastewater after radiation treatment was evaluated. The results of this study could provide an insight into the removal of ammonia and phenol from saline chemical wastewater by radiation technology.
含氨和有毒有机污染物的盐水化学废水一直是传统废水处理技术的挑战。因此需要进行高级处理。本研究详细研究了辐射去除盐水化学废水中的氨和酚。结果表明，辐射可以将盐水化学废水中的氯离子转化为•Cl 和•ClO，这促进了氨的氧化，但抑制了酚的降解。溶液 pH 影响反应性物质的类型，从而进一步影响氨和酚的去除。当氨和酚同时存在于盐水化学废水中时，与不存在酚的情况相比，氨的去除效率降低。同样，当溶液 pH 低于 7.0 时，氨的存在也会降低酚的去除效率。有趣的是，随着氯离子浓度（2-8 g/L）或剂量（2-5 kGy）的增加，酚的去除效率也得到了提高，这归因于形成了可以与酚反应的中间氮中心自由基。此外，还确定了不同条件下酚降解的中间产物。评估了辐射处理后盐水化学废水的急性毒性。本研究的结果可为辐射技术去除盐水化学废水中的氨和酚提供深入了解。
