ABSTRACT

The massive drawbacks of conventional wastewater treatment have led to a demand investigation about new advanced wastewater treatment technology. The issue can be addressed via advanced oxidation processes (AOPs) as witnessed recently. Therefore, the objective of this study was to investigate the performance of ozone/persulfate (${\mathrm{O}}_3/{\mathrm{S}}_2{\mathrm{O}}_8^{2-}$) process to assess its use as potential degradation of diazo dye which is Reactive Green 19 (RG19). In this work, efficiency, color, and COD removal were investigated over a range of initial pH, persulfate concentration and initial concentration of RG19. The amount of sodium persulfate ($\mathrm{N}{\mathrm{a}}_2{\mathrm{S}}_2{\mathrm{O}}_8$) was varied at different levels (20–100 mM) relative to precursor radical to assess the optimum usage of persulfate concentration for RG19 degradation. Evidence that RG19 could degrade efficiently had occurred at 100 mg/L, initial pH 9, 60 mM persulfate concentration was identified by FTIR and GC/MS analysis. The results revealed that RG19 could achieve complete decolorization easily as compared to mineralization. In addition, RG19 degradation pathway gave the best representation of level degradation. The GC/MS and FTIR results exhibited the proposed RG19 degradation pathway that involved the characteristic of sulfonic group, $\mathrm{H}{\mathrm{O}}^{\bullet }$ accompanied with ${\mathrm{S}\mathrm{O}}_4^{-}$ became as an indicator of their structure broken down one by one. The degradation products such as oxalic acid, formic acids and others were analyzed and finally converted to carbon dioxide and water. The diazo dye structure itself aided with $\mathrm{N}{\mathrm{a}}_2{\mathrm{S}}_2{\mathrm{O}}_8$ has its superior characteristic as an aid for the efficient degradation process.

摘要

传统废水处理的巨大缺陷导致了对新型先进废水处理技术的需求调查。正如最近所见证的那样，这个问题可以通过高级氧化工艺 (AOP) 来解决。因此，本研究的目的是研究臭氧/过硫酸盐的性能（${\mathrm{○}}_3/{\mathrm{小号}}_2{\mathrm{○}}_8^{2-}$) 过程来评估其作为活性绿 19 (RG19) 重氮染料潜在降解的用途。在这项工作中，研究了在初始 pH 值、过硫酸盐浓度和 RG19 初始浓度范围内的效率、颜色和 COD 去除率。过硫酸钠的量（$\mathrm{ñ}{\mathrm{一个}}_2{\mathrm{小号}}_2{\mathrm{○}}_8$）相对于前体自由基在不同水平（20-100 mM）下变化，以评估过硫酸盐浓度对 RG19 降解的最佳使用。通过 FTIR 和 GC/MS 分析确定 RG19 可以有效降解的证据发生在 100 mg/L、初始 pH 9、60 mM 过硫酸盐浓度。结果表明，与矿化相比，RG19更容易实现完全脱色。此外，RG19降解途径给出了水平降解的最佳表现。GC/MS 和 FTIR 结果显示了所提出的 RG19 降解途径，该途径涉及磺酸基团的特征，$\mathrm{H}{\mathrm{○}}^{\bullet }$伴随着${\mathrm{小号}\mathrm{○}}_4^{-}$成为他们结构的指标，被一一分解。对草酸、甲酸等降解产物进行分析，最终转化为二氧化碳和水。重氮染料结构本身有助于$\mathrm{ñ}{\mathrm{一个}}_2{\mathrm{小号}}_2{\mathrm{○}}_8$具有作为有效降解过程的辅助剂的优越特性。