Abstract:
The non-free radical oxidation pathway (PMS-NOPs) of peroxymonosulfate (PMS) holds significant promise for practical wastewater treatment applications, owing to its low oxidation potential, high PMS utilization rate, and robust anti-interference capability in the degradation of pollutants. A novel activator copper nitrogen co-doped porous biochar (Cu-N-BC) with rich defect edges and functional groups was obtained by adding Cu and N to the biochar matrix generated by sodium alginate through pyrolysis in this study. Under the condition of 1 mM PMS, 30 mg/L activator was used to activate PMS and achieve efficient degradation of 10 mg/L paracetamol (PCT) within 15 min, with a high reaction rate constants (kobs) of 0.391 min-1. The activation mechanism of the Cu-N-BC/PMS/PCT system was a non-radical activation pathway with the dominance of singlet oxygen (1O2) and the presence of catalyst-mediated electron transfer. The graphite nitrogen, pyridine nitrogen, and Cu-N coordination introduced by Cu/N co-doping, as well as the carbon skeleton and CO functional group of biochar, were considered active sites that promote the 1O2 generation. The Cu-N-BC/PMS system exhibits strong stability, eco-friendliness, effective mineralization, and interference resistance across diverse pH levels (3-11) and interfering ions, including Cl-, H2PO4-, NO3-, SO42-, and humic acid. Remarkably, it efficiently degrades PCT in tap and lake water, achieving a notable 63.73% TOC mineralization rate, with leached copper ions below 0.02 mg/L. This research introduces a novel method for obtaining metal nitrogen carbon activators and enhances understanding of PMS non-radical activation pathways and active sites.
摘要:
过氧单硫酸盐(PMS)的非自由基氧化途径(PMS-NOPs)在实际废水处理应用中具有重要的前景。由于其氧化电位低,高PMS利用率,和强大的抗干扰能力在污染物的降解。通过将Cu和N添加到海藻酸钠通过热解产生的生物炭基质中,获得了一种具有丰富缺陷边缘和官能团的新型活化剂铜氮共掺杂多孔生物炭(Cu-N-BC)。在1mMPMS条件下,使用30mg/L活化剂活化PMS,在15min内实现10mg/L对乙酰氨基酚(PCT)的高效降解,具有0.391min-1的高反应速率常数(kobs)。Cu-N-BC/PMS/PCT系统的活化机理是非自由基活化途径,单线态氧(1O2)占优势,存在催化剂介导的电子转移。石墨氮,吡啶氮,和Cu/N共掺杂引入的Cu-N配位,以及生物炭的碳骨架和CO官能团,被认为是促进1O2生成的活性位点。Cu-N-BC/PMS体系具有较强的稳定性,生态友好,有效矿化,以及对不同pH值(3-11)和干扰离子的抗干扰性,包括Cl-,H2PO4-,NO3-,SO42-,和腐殖酸。值得注意的是,它有效地降解自来水和湖水中的PCT,达到63.73%的TOC矿化率,浸出的铜离子低于0.02mg/L这项研究介绍了一种获得金属氮碳活化剂的新方法,并增强了对PMS非自由基活化途径和活性位点的理解。