Regeneration of tri-octyl phosphine oxide solutions used to extract phenol from water

Technical Report · Mon Aug 01 04:00:00 EDT 1983

OSTI ID:5745763

Bixby, J L; King, C J

Several potential extractant diluents were examined. Distillation was investigated for regenerating tri-octylphosphine oxide solutions loaded with phenol. Relative volatilities of phenol to the diluent were measured for the diluents isobutyl-heptyl ketone and dimethylnaphthalene, at both varying solute-to-extractant mole ratios and extractant concentrations in the solvent. A simple model based on the chemical complexation between the solute and extractant is proposed. The equilibrium constant for this reaction was determined to be roughly 5 L/gmole. Equilibrium distribution coefficients were also measured for the extraction of phenol from both pure water and coal-gasification condensate water, by a mixed TOPO solvent having acceptable regeneration capabilities. These data are consistent with the extraction mechanism model previously proposed by MacGlashan (1982). Losses of the extractant into the aqueous raffinates are also reported. Both the observed high distribution coefficients at low solute-to-extractant mole ratios, and the low relative volatilities indicate that the association between phenol and TOPO is strong. Hence, a high boiling diluent is needed for favorable regeneration via distillation. TOPO-based solvent extraction appears to be best suited for treatment of aqueous solutions having phenol concentrations on the order of 100 parts per million.

• Research Organization: Lawrence Berkeley Lab., CA (USA)
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 5745763
• Report Number(s): LBL-16577; ON: DE84000938
• Country of Publication: United States
• Language: English

Related Subjects

520200* -- Environment
Aquatic-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
AROMATICS
DISTILLATION
EXTRACTION
HYDROXY COMPOUNDS
KETONES
ORGANIC COMPOUNDS
ORGANIC PHOSPHORUS COMPOUNDS
PHENOLS
RECOVERY
REGENERATION
REMOVAL
SEPARATION PROCESSES
SOLVENT EXTRACTION
TOPO
USES