Phenol recovery using continuous emulsion liquid membrane (CELM) process

Abstract

Liquid membrane technology in batch operation is not quite feasible at industrial level. Hence, a continuous emulsion liquid membrane (CELM) process was conducted in this study to extract phenol from liquid waste solution. An extractor of 1.5 L equipped with baffles was used for well mixed during the extraction process. ELM formulation consists of a mixture of kerosene and palm oil, span 80 and sodium hydroxide as a diluent, surfactant, and strippant, respectively. Meanwhile, 300 ppm of simulated phenol wastewater was used as a feed phase. ELM was found to be stable at 3% (w/v) of Span 80, 5 min of emulsification time and 1300 rpm of emulsification speed. Then, parameters influencing recovery were optimized using the response surface methodology including rotational speed (400 to 800 rpm), treat ratio (1:3 to 1:10) and retention time (2 to 6 min). Increasing rotational speed, treat ratio, and retention time up to 527 rpm, 1:4 and 4 min, respectively offer high recovery efficiency of phenol when achieving about seven times enrichment in the internal phase (2100 ppm).