الفهرس 
dye removal techniques
experimenalOnly 14 pages are availabe for public view
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Abstract
This work is concerned with the kinetics of decolorization of the three dyes,
triarylmethane dye Brilliant green (BO), azo dyes Oirect red 31 (OR31) and
Reactive red 4 (RR4) in aqueous solution using potassium peroxydisulfate in the
presence and absence of light irradiation. The thesis consists of three chapters.
Chapter 1 includes the literature survey of the techniques used for wastewater
treatment and the removing of water pollutants by peroxydisulfate in the presence
and absence of Ag + ion as catalyst.
Chapter 2 describes the materials and the experimental methods used to monitor
the reaction.
Chapter 3 includes the results and discussion. It is divided into two parts. The first
part deals with the reaction of the current dyes with S20g 2- in the absence of UV-
light. The uncatalyzed oxidation process was so slow but was accelerated
tremendously upon the incorporation of Ag+ as a catalyst for only OR3l, RR4
dyes. It was investigated by monitoring the decrease of absorbance at Alllax= 625,
517 and 525 nm for BO, RR4 and OR31, respectively. The concentrations were
adjusted to suit pseudo-first order conditions with respect to the dye
concentration. It was found that the observed rate constant (kohs) of the reaction
increased with increasing the concentration of the dye until certain concentration
then remained constant for the BO but the kobs decreased in OR3l, RR4. The
effect of S20g 2- and Ag + concentration was investigated. The reaction rate
increased with increasing the concentration of the reactants as well as with
increasing the concentration of Ag +. The rate constant was int1uenced by the pH of
the medium and the presence of KCl and K2S04. The decolorization of the three
dyes followed two different mechanisms according to the presence and absence of
Ag” ion and the reaction was enthalpy controlled.