The search is focused on application of the catalase enzyme in the
dyeing bath at different temperatures and concentration to catalyze
the peroxide remaining after bleaching the fabrics of cotton and
study its effect on exhaustion and fastness of reactive dye and
compare these results with sample is dyed in clean water path
without the presence of the enzyme.
Paper mill wastewater is an environment contaminated wastewater , and refractory to biological treatment due to its high value of COD and low value of BOD_5.
This research studies the treatment of mentioned wastewater using Fenton Oxidation Fe^(2+)/
H_2 O_2. The effect of some key elements on this oxidation such as H_2 O_2 and Fe^(2+) doses, dosage strategy of H_2 O_2, with a pH value near 3 was studied. Fenton method showed high efficiency of COD removal reached 78.5 % with a total hydrogen peroxide dose of 2.2g/l applied in four doses and intervals of 15min.
Experiments also proved that intermittent dosage - four doses - are better than giving whole dose in one stroke. Results appeared evidently in two points: the efficiency of COD removal and the ratio of BOD5/COD; since we reached through intermittent dosages a value of BOD5/COD near 0.32 , which eventually allows effluent from Fenton oxidation process to be treated biologically.
This study aims to shed light upon bleaching process, study the
influence of each substance during the process and the best time for
bleaching in addition to clear up the effect of water.
The present study aimed to investigate the capacity of biotin in preventing
oxidative stress induced by hydrogen peroxide H2O2 at a concentration of 1%
given with consumed drinking water to local male rabbits. 40 male rabbits aged
7-8 months, were
used in this study and were divided randomly into four
groups, with 10 rabbits within group, as follow: the first group was given
standard forage and normal water and considered as control, the second group
was given standard forage and 1% H2O2 in water, the third group was given
standard forage and 200 mg biotin /kg body weight in water, the fourth group
was given standard forage, 1% H2O2 and 200 mg biotin /kg body weight in
water. All groups were treated daily for 8 weeks.
Phenolic compounds are known to be present in high concentration
in various of agro industrial wastes such as olive mill wastewater. As
they are highly biorecalcitrant a possible treatment by Advanced
Oxidation Processes has to be investigated.
T
he photocatalytic degradation of the phenolic acids p-Hydroxybenzoic
acid, Dihydroxybenzoic acid, gallic acid, vanillic acid, syringic acid) in the
presence of TiO2 deposit on a glass plate has been reported. A comparison for
the adsorption properties and the kinetics of reaction have been studied. The
kinetics were found to be first order for all compounds and were compared
with the compounds’ structures. The reaction rate for the compounds was
found as the order Di-HBA < GA < p-HBA ≈ SA ≈ VA.
The influence on the photdegradation rate of various parameters as pH, and
substrate’s concentration was studied for p-Hydroxybenzoic acid only. It was
found that the reaction is pH and substrate’s concentration dependence.
A removal efficiency (50-70%) was determined after 5hr using UVlamp
(15W- λ=360nm) and it increased up to 95% when H2O2 was
added.
During the past few years attention has been drawn on chemical techniques
that could be used to discolour textile wastewaters. We have studied the
photocatalytic degradation of various dyes (Methyl orange, Azo carmine B,
Coomassie Brilliant blue G
250, Tartrazine, Calcon, Eriochrome blue SE,
Solamine Red 4BL, Bismarck brown Y(G), Methylen blue, Black 5, Red 120,
Morin) using TiO2 P25 Degussa as catalyst. All dye solutions underwent a
decolourization. The kinetics of reaction have been studied and were found to
be zero or first order with respect to the dye. It was compared with the
adsorption properties. The effect of the addition of hydrogen peroxide has been
studied. An enhancement of the rate has been observed in all cases and the
order with respect to the dye's concentration in presence of the additive seemed
not to change. It is difficult to give general view of the kinetics using these very
different dyes but the process was found to be effective for the decolourization
of textile wastewater.
