טכניון מכון טכנולוגי לישראל
הטכניון מכון טכנולוגי לישראל - בית הספר ללימודי מוסמכים  
M.Sc Thesis
M.Sc StudentMeirav Ezon
SubjectPre-Oxidation by Fenton's Reagent to Enhance
Biodegradability of Aminophenols
DepartmentDepartment of Civil and Environmental Engineering
Supervisor Professor Emeritus Narkis Nava


Abstract

Toxic materials generally originate from the chemical industry. Most of the industrial wastewaters are stable to biodegradation in surface water, and industrial wastewater treatment plants.

Many of these compounds are highly toxic, carcinogenic or mutagenic, therefore they must be effectively destroyed by the specific industrial waste treatment, before their disposal to municipal sewage treatment plant or to the environment.

The aim of this research is to examine the use of chemical oxidation using a hydrogen peroxide pre-treatment in order to enable and enhance the biodegradation of aminophenol compounds among them the 3-Aminophenol, 3AP.

The research was divided into two stages: 1. Studying the chemical oxidation of aqueous solutions of 3AP at 50 mg/L ,and at 1000 mg/L concentration by using hydrogen peroxide  at pH 3.5.

The oxidation of 3AP showed that hydrogen -peroxide by itself was insufficient and it required the presence of the catalyst Fe2+.

It can be observed that the oxidation in the presence of Fe2+ dramatically increased the oxidation reaction and its efficiency.

Increasing the Fe2+concentration level improves the 3AP oxidation efficiency.       

2. At this stage the biodegradation of 3AP and pre-oxidized 3AP by Fenton reagent     solutions as a sole carbon source were studied.

It was found that 50 mg/L and 1000 mg/L 3AP solutions are not toxic to the acclimated and  unacclimated activated sludge microorganisms.

The pre-oxidation using Fenton’s reagent enhanced the biodegradation of 3AP up to the stage where a high concentration of toxic byproducts such as oxalic acid is formed.

As a result of the high toxic byproducts concentration, the biodegradation was found un efficient.