The Continuous Foam Fractionation of Phenol

Abstract
The continuous foam fractionation of phenol using a quaternary ammonium salt, ethylhexadecyldimethylammonium bromide, has been investigated. Experiments were conducted to determine the effects of pH and percentage reflux on the phenol removal. It was found that approximately 80% removal of phenol was obtained at a pH of 11.9 with 70% reflux. Poor removal occurred in the slightly basic region of 8.0 to 10.0; while adequate removal was obtained with no pH adjustment. Maximum removal occurred at 70 to 80% reflux. Sodium hydroxide was used to adjust the pH in most cases. Although similar effects were found using ammonium hydroxide, the percent removal of phenol was, in general, lower.