COMBINED PERSULFATE AND CLINOPTILOLITE FOR THE REMOVAL OF COD AND SUSPENDED SOLIDS FROM A REAL DYE WASTEWATER

In the production of textile fabrics, the unfixed dye that is left in the process wastewater often show a significant influence of pollution, either in any receiving surface water or the extra burden of the pollution load in a receiving sewer. However, besides the unfixed dyes, other pollutants generated in the various stages of textile production have contributed to the strength and variability of the pollutants inherent in the resultant wastewater. Therefore, the present study characterizes a real textile wastewater and investigates the feasibility and success of the combination of persulfate and clinoptilolite in a single reactor to remove the target pollutants viz; chemical oxygen demand (COD) and suspended solids (SS). Results of the study show that the combination is feasible and successful in the treatment of recalcitrant dye wastewater. This is indicated by the removal of COD (74%) and SS (99%). The determinant factors that were observed to effectively influence the treatment process were persulfate dosage (4/1), which was standardized as a persulfate/contaminant ratio (g/g), dosage of clinoptilolite (8g), the initial pH (4) of reaction and reaction time of 30 minutes to remove COD, and 210 minutes for the removal of SS. The residual SS at 3 mg/l is within the acceptable limit of 50 mg/l, while the COD exceeded the standard limit. A biological treatment may thereafter be applied to further remove the residual COD to bring to an acceptable limit.