Removal of Toxic Eosin Y Dye from Water Samples by Cloud Point Extraction using Triton X-114 as Nonionic Surfactant

A surfactant mediated cloud point extraction (CPE) has been developed to remove color from wastewater containing toxic Eosin Y dye, using Triton X-114 (TX-114) as nonionic surfactant. Most of the dye molecules become solubilized in the coacervate phase leaving dilute phase free of dyes. The effects of surfactant concentration, temperature and salt concentration on the extraction yield of the dye have been investigated and the optimum conditions were obtained for the removal of toxic Eosin Y. It was found that phase separation was complete and the recovery of Eosin Y was very effective in the presence of NaCl as an electrolyte. The results showed that up to 20 ppm of Eosin Y, more than 97% can quantitatively be removed by cloud point extraction procedure in one single extraction at optimum conditions. In addition, it was observed that at a dye concentration of 5 ppm and a Triton X-114 concentration of 2.75 wt%, 99% of the dyeeosin Y can be removed. At 50 C, a dye removal of 96.8%-99% can be achieved with a higher dye concentration of up to 25 ppm when 2.75 wt% Triton X-114 and 0.02 M salt (NaCl) are present. It is concluded that the cloud point extraction techniques for the dye removal may be an alternative to the present dye removal processes.