However, the problem of the scavenging effect is an aspect that needs to be dealt with, as hydroxyl radicals are prone to deactivation by scavengers. Sonolysis as an auxiliary tool has potential to induce synergetic effects in combination with Advanced Oxidation Processes to increase in-situ hydrogen peroxide production. Furthermore, optimization of operating parameters can result in an increase in the yield of hydroxyl radicals/hydrogen peroxide. From this review, it can be concluded that hydroxyl radical is highly oxidative and non selective in nature and its in-situ production can be performed through application of catalyst, ozonation, photocatalysis, electro and microbial fuel cells. Additionally the scavenging aspect for hydroxyl radicals was also investigated. In this paper, a detailed review was conducted on the generation methods, degradation potential and optimum operating parameters for in-situ production of hydrogen peroxide/hydroxyl radicals. Composition, : Sodium Chloride 99.67, Eriochrome Black T 0.33. One of the means to overcome this problem is the in-situ production of hydrogen peroxide. Besides, industrial grade hydrogen peroxide costs $390 e500 per ton. However, excessive use of hydrogen peroxide and catalyst has made this process economically non-feasible. The best treatment results were obtained with the Fenton process, which under the optimal pH equal to 3 and hydrogen peroxide and ferrous sulphide dose of 600 and 550 mg dm−3, respectively, resulted in a final effluent being colourless and with the residual COD equal to 100 mg dm−3.įenton Process, a type of Advanced Oxidation Processes is an efficient method for treating textile wastewaters. Indirect oxidation, by means of chlorine-deriving compounds, was the predominating process leading to the pollutants depletion. Under the conditions of an acidic pH in 40 min of electrolysis a 79% elimination of COD was achieved at the Ti/Pt–Ir anode, which proved the best of seven different tested materials. Trials of electrochemical oxidation proved this process much more efficient. A high decolourisation degree was however accompanied by a low removal (10% efficiency) of chemical oxygen demand (COD). While the results obtained during hypochlorite oxidation were not satisfactory (only 35% reduction of colour was achieved at a dose of 6 g dm−3), ozonation enabled colour to be reduced by up to 90% (ozone dose 0.5 g dm−3). IJSER is an open access international journal or a large number of high quality and peer reviewed research publishing in all the fields of science. The results of an experimental study on the destruction of disperse dyes by chemical oxidation using ozone, hypochlorite and Fenton reagent (H2O2+Fe2+) are compared with the data obtained by electrochemical oxidation.
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