Can electrochemical oxidation techniques really decontaminate saline dyes wastewater?. Issue 3 (September 2015)

• Record Type: Journal Article
• Authors: Ramjaun, Sadiqua N.; Wang, Zhaohui; Yuan, Ruixia; Liu, Jianshe
• Is Part Of: Journal of environmental chemical engineering. Volume 3:Issue 3(2015:Sep.)
• Page Start: 1648
• Page End: 1653
• Publication Date: 2015-09
• Subjects: Textile wastewater -- Chloride -- Chlorinated byproducts -- Hydroxyl radicals; Chemical engineering -- Environmental aspects -- Periodicals; Environmental engineering -- Periodicals; Chemical engineering -- Environmental aspects; Environmental engineering; Periodicals; 660.0286
• DOI: 10.1016/j.jece.2015.06.006
• Languages: English
• ISSNs: 2213-2929

Abstract

Highlights: Effect of chloride ions on electrochemical degradation kinetics of dye was examined. MO degradation was significantly enhanced by higher concentrations of chloride. 32 chlorinated organic byproducts of MO were identified by GC–MS method. Abstract: Formation of toxic chlorinated organic byproducts is of great concern when selecting electrochemical oxidation (EO) as decontamination technology for saline dye wastewater, but still not verified. To test the applicability of EO, methyl orange (MO) was used as a model dye for anodic contact glow discharge electrolysis (CGDE) and conventional electrolysis (CE) in the presence of chloride. The degradation kinetics and organic intermediates were analyzed. In the presence of chloride, the rates of dye degradation were significantly increased as CGDE and CE were applied. CE resulted in higher mineralization efficiency than CGDE which needs much energy input. Several refractory chlorinated aromatic and even aliphatic compounds were identified during MO degradation, as well as the other anthraquinone dye, alizarin red S (AR). Therefore, the issues of toxic chlorinated byproducts and energy cost should be preferentially evaluated prior to the selection of EO technologies.