Efficient complex extraction of Telon yellow 4R from dye wastewater and its optimization using the response surface methodology

The efficient removal of sulfonic dyes in wastewater needs to be done urgently in the dyeing industry. In the work, the extraction rates of the different extractants, the dissolving accelerants and the diluents were compared, and the optimal organic phase for Telon Yellow 4R wastewater was determined. The conditions of the complex extraction affecting the extraction rate of Telon Yellow 4R solution were studied. The complex extraction model was established based on the central composite design - response surface method. The results show that the trioctylamine volume fraction, the n-octanol volume fraction, the aqueous-organic phase ratio, and the pH value are the four significant influencing factors affecting the extraction rate; the order of the significance of these factors is: the aqueous-organic phase ratio > the trioctylamine volume fraction > the n-octanol volume fraction > the pH value; the optimal extraction conditions under which the extraction rate of Telon Yellow 4R reached 98.3% are the trioctylamine volume fraction of 22.5%, the n-octanol volume fraction of 33.3%, the pH value of 2.2, and the aqueous-organic phase ratio of 1.9.