Year

1982

Degree Name

Doctor of Philosophy

Department

Department of Chemistry

Abstract

A new process for the detoxification of aqueous phenol solutions has been examined on a laboratory scale. Fenton's reagent (ferrous salts/hydrogen peroxide) was used to oxidize the monohydric phenols to polyhydric phenols and these were further oxidized either aerially or chemically in the presence of polyamine polyelectrolytes to form an adduct which could be removed by sedimentation. Substantial reductions in both phenol and total organic carbon (TOC)concentrations were achieved without the necessity to degrade the phenol to its ultimate oxidation product, carbon dioxide.

Polyethyleneimine was the most efficient of the polyamines studied and its efficiency increased with increasing molecular weight.

Substituted phenols were oxidized in order to establish the optimum conditions for the Fenton's reagent oxidation and the effect of phenolic substituent type and substitution pattern on the rate and extent of TOC reduction. The reaction appears to be applicable even to highly substituted phenols provided at least one vacant ortho position is available for hydroxylation. Continuous variation and yield optimization experiments suggest that the adduct is only approximately stoichiometric (with about one phenol unit per nitrogen atom) and that the bonding between these units is consistent with two mechanisms proposed previously for the interaction of humic materials with amines.

Although the procedure does not alone reduce the phenol concentration to the desirable 0.1 mg/L discharge level, it does show potential as a pre-treatment of high strength phenolic effluents to be later processed by a biological treatment system.

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Unless otherwise indicated, the views expressed in this thesis are those of the author and do not necessarily represent the views of the University of Wollongong.