An efficient cloud point extraction method for the separation of congo red using Triton X-100 in the presence additives

A new approach to improve the cloud point extraction of congo red (a hazardous anionic azo dye) from aqueous solution using Triton X-100 surfactant is reported. The interaction of congo red with Triton X-100 during micellar solubilization has also been investigated by visible absorption spectral studies. The optimum conditions for surfactant concentration, additives (salts, glycols and their ethers) concentration, temperature and pH have been determined to achieve higher extraction. Among the various glycol ethers studied, ethylene glycol monohexyl ether shows the most efficient extraction of the dye even at ambient temperature, with almost complete removal of the dye from aqueous solution.