Butyl acetate replaces toluene to remove phenol from water

Plastics Engineering Co. manufactures phenol formaldehyde resins and molding compounds at a plant in Sheboygan, WI. Process water from the plant, containing 7% phenol and 1% methanol, requires treatment prior to discharge to the sewer. Toluene was used as a solvent in a countercurrent liquid-liquid extraction column. A vacuum distillation of the extract separated the phenol and toluene. The raffinate (1% methanol, 98% water and 1% toluene) was stripped to recover the toluene and remove methanol from the bottoms prior to discharge. Methanol was not recovered. Disposal costs for the waste methanol (with about 10% toluene as an azeotrope) were high.