Moraes Peterson B, Pelegrino Rosangela R L, Bertazzoli Rodnei
Department of Materials Engineering, Faculty of Mechanical Engineering, Campinas State University, Campinas, SP, Brazil.
J Environ Sci Health A Tox Hazard Subst Environ Eng. 2007 Dec;42(14):2131-8. doi: 10.1080/10934520701629591.
In this paper, electrochemical and photo-assisted electrochemical processes are used for color, total organic carbon (TOC) and chemical oxygen demand (COD) degradation of one of the most abundant and strongly colored industrial wastewaters, which results from the dyeing of fibers and fabrics in the textile industry. The experiments were carried out in an 18 L pilot-scale tubular flow reactor with 70%TiO(2)/30%RuO(2) DSA. A synthetic acid blue 40 solution and real dye house wastewater, containing the same dye, were used for the experiments. By using current density of 80 mA cm(-2) electrochemical process has the capability to remove 80% of color, 46% of TOC and 69% of COD. When used the photochemical process with 4.6 mW cm(-2) of 254 nm UV-C radiation to assist the electrolysis, has been obtained 90% of color, 64% of TOC and 60% of COD removal in 90 minutes of processing; furthermore, 70% of initial color was degraded within the first 15 minutes. Experimental runs using dye house wastewater resulted in 78% of color, 26% of TOC and 49% of COD in electrolysis at 80 mA cm(-2) and 90 min; additionally, when photo-assisted, electrolysis resulted in removals of 85% of color, 42% of TOC and 58% of COD. For the operational conditions used in this study, color, TOC and COD showed pseudo-first-order decaying profiles. Apparent rate constants for degradation of TOC and COD were improved by one order of magnitude when the photo-electrochemical process was used.
本文采用电化学和光辅助电化学方法，对纺织工业中纤维和织物染色产生的一种含量丰富且颜色深的工业废水进行颜色、总有机碳（TOC）和化学需氧量（COD）的降解处理。实验在一个18升的中试规模管式流动反应器中进行，该反应器装有70%TiO(2)/30%RuO(2)尺寸稳定阳极（DSA）。实验采用了合成酸性蓝40溶液和含有相同染料的实际印染厂废水。在电流密度为80 mA cm(-2)时，电化学过程能够去除80%的颜色、46%的TOC和69%的COD。当使用4.6 mW cm(-2)的254 nm UV-C辐射的光化学过程辅助电解时，在90分钟的处理过程中，颜色去除率达到90%，TOC去除率为64%，COD去除率为60%；此外，在前15分钟内，70%的初始颜色被降解。使用印染厂废水进行的实验表明，在80 mA cm(-2)和90分钟的电解过程中，颜色去除率为78%，TOC去除率为26%，COD去除率为49%；此外，当采用光辅助时，电解导致颜色去除率为85%，TOC去除率为42%，COD去除率为58%。对于本研究中使用的操作条件，颜色、TOC和COD呈现伪一级衰减曲线。当采用光电化学过程时，TOC和COD降解的表观速率常数提高了一个数量级。
