Decolorization process of dye wastewater containing methyl orange by foam separation method

In order to develop a dye wastewater decolorization method featured by simple process,low cost and non-secondary pollution,the decolorization process of wastewater by foam separation was studied by using methyl orange aqueous solution as a research system.The influences of pH value,gas flow rate,mass concentration of the surfactant and volume of the solution on the decolorization process were investigated.The results show that taking surfactant,i.e.hexadecyl trimethyl ammonium bromide(CTAB)as collecting agent,the optimum conditions are pH 6.0,gas flow rate 0.04 m3/h,mass concentration of CTAB 90 mg/L and volume of the solution 1 000 mL.Under the optimum conditions,the first-time decolorization enrichment ratio β is 111.0 and decolorization rate is 99.5%.Then,the reuse of the foamate was studied by filtrating foamate,pouring the filtrate and adding CTAB in the dye wastewater.When the molar ratio of the additional CTAB to methyl orange is 0.89 ∶1,the second-time decolorization rate is 99.4% and enrichment ratio is 50.