4.7 Article

Kinetics of three commercial textile dyes decomposition by UV/H2O2 and UV/acetone processes: An experimental comparative study and DFT calculations

期刊

JOURNAL OF MOLECULAR LIQUIDS
卷 383, 期 -, 页码 -

出版社

ELSEVIER
DOI: 10.1016/j.molliq.2023.122212

关键词

Dyes; Degradation; Hydrogen peroxide; Acetone; UV; Chemical structure; DFT

向作者/读者索取更多资源

In this study, acetone photolysis was compared with the UV/H2O2 process for the removal of three commercial textile dyes in aqueous solution. The results showed that UV/acetone exhibited better removal efficiency than UV/H2O2, with higher decolorization rates for all dyes. Scavenging tests revealed that different radicals were responsible for the degradation of dyes in the two processes.
Acetone photolysis was investigated and compared with the UV/H2O2 process for the removal of three com-mercial textile dyes, Reactive Red 184 (RR184), Reactive Orange 4 (RO4), and Direct Red 80 (DR80), in aqueous solution at 254 nm, pH = 6.5-6.8, and T = 20 +/- 2 degrees C. The removal efficiency of RR184, RO4, and DR80 by UV/ H2O2 was 35 %, 59 %, and 69 %, respectively, whereas UV/acetone exhibited a removal efficiency of 81 %, 99 %, and 88 %, within 30 min ([Dye]0 = 0.1 mM and [acetone]0 = [H2O2]0 = 50 mM). However, as the initial doses of H2O2 and acetone were increased, the decolorization increased, and the experimental kinetic data always agreed with the pseudo-first-order reaction model (R2 = 0.94-0.99). Additionally, UV/acetone was consistently shown to be significantly more efficient than UV/H2O2 under all conditions tested. For instance, the rate constant ratios kUV/acetone/kUV/H2O2 are 3.19, 1.95, and 1.67 for RR184, RO4, and DR80, respectively ([Dye]0 = 0.1 mM and [acetone]0 = [H2O2]0 = 50 mM). Scavenging tests using specific probes revealed that center dot OH and center dot CH3 radicals were the main responsible for dyes degradation (greater than80 %) in the UV/H2O2 and UV/acetone processes, respectively. In both systems, the dyes' reactivity order was found to be RO4 > DR80 > RR184, indicating that chemical structure is an important factor in evaluating the efficiency of the degradation process. This reactivity order was supported by the density functional theory (DFT)-based thermodynamic calculations used to explain the HO center dot-initiated degradation of the studied azo dyes in the UV/H2O2 process.

作者

我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。

评论

主要评分

4.7
评分不足

次要评分

新颖性
-
重要性
-
科学严谨性
-
评价这篇论文

推荐

暂无数据
暂无数据