ABSTRACT

Recently, the micro-nano bubble (MB) technology has attracted people's attention due to its special advantages. Here, we carried out the technology of combining MB and hydrogen peroxide (MB/H₂O₂) to achieve efficient degradation of tetracycline wastewater. The effect of MB/H₂O₂ technology on the degradation efficiency of tetracycline was deeply analysed by investigating the reaction time, H₂O₂ dosage, pH and MB inlet flow. The results showed that the degradation rate of tetracycline hydrochloride by MB/H₂O₂ technology can reach 92.43%, which is 9.44 and 3.94 times that of MB and H₂O₂ alone. Through electron spin resonance (ESR) analysis and free radical quenching experiments, a possible mechanism for MB/H₂O₂ technology to efficiently degrade TC was proposed. In the MB/H₂O₂ system, the high temperature and high pressure environment generated when MB ruptures can activate H₂O₂ to obtain a higher number of active oxygen species. •OH is the main reactive oxygen radical in the process of MB/H₂O₂ degradation of TC, followed by HO₂•/•O₂-. In addition, the possible intermediate products of the oxidation TC process were identified by HPLC-MS technology. Under the action of •OH and HO₂•/•O₂− free radicals, TC molecules undergo demethylation and hydroxylation, ring-opening reactions, isomerization, deethylation, deacylation, deamination and dehydration reactions to generate intermediate products and finally convert them into CO₂ and H₂O. The development of MB/H₂O₂ technology can potentially be used to efficiently remove TC substances in the water environment and provide a new method for water purification.

摘要

近来，微纳气泡（MB）技术因其特殊的优势而受到人们的关注。在这里，我们开展了MB与过氧化氢（MB/H ₂ O ₂）结合的技术，实现了四环素废水的高效降解。_{通过考察反应时间、H 2} O ₂用量、pH值和MB入口流量，深入分析了MB/H ₂ O ₂工艺对四环素降解效率的影响。结果表明，MB/H ₂ O ₂技术对盐酸四环素的降解率可达92.43%，是MB和H ₂ O _{2的9.44倍和3.94倍。}独自的。通过电子自旋共振（ESR）分析和自由基猝灭实验，提出了MB/H ₂ O ₂技术高效降解TC的可能机理。在MB/H ₂ O ₂体系中，MB破裂时产生的高温高压环境可以激活H ₂ O ₂以获得更多的活性氧。_{•OH是TC降解MB/H 2} O ₂过程中的主要活性氧自由基，其次是HO ₂ •/•O ₂-。此外，通过 HPLC-MS 技术鉴定了氧化 TC 过程中可能存在的中间产物。在•OH和HO ₂ •/•O ₂ - 自由基的作用下，TC分子发生去甲基化和羟基化、开环反应、异构化、去乙基化、脱酰化、脱氨化和脱水反应生成中间产物，最终转化为CO ₂和H ₂ O。MB/H ₂ O ₂技术的发展可潜在用于高效去除水环境中的TC物质，为水净化提供新的方法。