Treatment of dyes wastewater by combination method using oxidation and coagulation.

Industrial waste containing dyes is difficult to process. Effective and efficient waste treatment technology is needed to treat dye waste. This study conveys the results of processing dye waste using a combined method of oxidation with hydrogen peroxide and coagulation using alum. The research parameter analysed was Chemical Oxygen Demand (COD) using a UV-Visible spectrophotometer. This study was influenced by several factors, namely the concentration of H₂O₂, stirring time, volume of H₂O₂ and variations in the addition of alum mass. The results showed that the reduction in COD with hydrogen peroxide concentration of 10%, stirring time for 40 minutes, volume of hydrogen peroxide as much as 1 mL, and alum dose of 2.5 g with an efficiency of decreasing COD concentration of 90.14%. The conclusion is that the combination of the two methods can be used as a pre-treatment method and further treatment is needed to produce COD levels that are in accordance with the waste quality standards. [ABSTRACT FROM AUTHOR]