Integrated advanced oxidation process, ozonation-electrodegradation treatments, for nonylphenol removal in batch and continuous reactor

Abstract

Nonylphenol has been reported as an Endocrine Disruptive Chemical and aquatic organisms have shown acutely and chronically toxicity when they are exposed to this organic pollutant. Many technologies have been applied searching to degrade or remove this contaminant from wastewater; however, few proposals addresses for the technology scale up and possible real application. In this study, the results of integrating electrochemical and ozone process are presented. It is possible to propose that in acidic media electrochemical degradation is faster than ozone treatment, for example at 60min of treatment, ozone showed a COD value of ca 30% degradation, whereas electrochemically 70% degradation was obtained. When the electrochemical process working in a continuous mode is applied (without prior O3 treatment), COD and TOC removal takes two times the period of time required when an initial ozone dose was applied. A cost comparison between the three processes reveals that the use of the sequenced treatment reduces the cost. Furthermore, when the cost of the sequenced process is compared against other process (UV/O3) the cost reduction is significant making the proposed system an attractive alternative for the treatment of persistent pollutants. Therefore, this technology proves to be highly effective, with low operational cost, simple operation and low environmental impact. Furthermore, no sludge is generated.