Removal of Remazol Rosso RB Dye from Aqueous Effluents by Homogenous Fenton Oxidation Processes

Abstract

Abstract. The paper presents some data from our laboratory-setup experiments of homogenous oxidative processes with hydrogen peroxide (i.e. advanced Fenton oxidation processes) applied for Remazol Rosso RB dye-containing aqueous systems, especially textile effl uents. Therefore, some different operating parameters (including pH, concentration of dye, H 2 O 2 and ferrous ions, oxidation time, temperature, stirring regime, among its) were tested for determination of the best performance in effl uent discoloration and dye removal, meaning the optimal values of each studied parameters for highest discoloration or dye removal. For an effl uent loaded with 50 mg/L Remazol Rosso RB dye, there were applied these optimal values that correspond to > 97 % discoloration effi ciency performed with 88.24 mM H 2 O 2 , 0.18 mM FeSO 4 , at pH (5.16), temperature of 19-20°C, continuous stirring regime (30 rpm) and minimum 25-30 minutes of homogenous advanced oxidation treatment. If there are not used additional chemical reagents for pH adjustment (minimization reason of treatment operating cost), the performance of this oxidative treatment is closed to above mentioned effi ciency by after a higher oxidation time (> 90 min). These results are encouraging and sustain this oxidative process application and optimization for reducing the environmental impact of effl uent discharging directly in different natural aquatic receptors and compliance with admissible limits imposed by environmental legislation as well.Keywords: discoloration, Fenton reagent, homogenous advanced oxidation process, optimal operating parameter, Remazol Rosso RB dye, textile effl uent treatment. IntroductionIn the whole world even in the most hardly accessible for tourist geographic zones, the water quality is negatively changing, and the pollution level of natural surface water resources is greatly increasing. One of the most important causes is the non-corresponding quality of fi nal colored or not effl uent discharged in natural water resources (water courses or accumulation lakes). Therefore, the wastewater or individual/fi nal effl uent treatment must continue to be one of priorities in environmental management (in terms of integrated production water management) even if an environmental prevention and control scheme was implemented in the productive/commercial unit for reduction of generated loaded wastewater amounts, among others. The treated effl uents are indicated to be inside recycling/ reuse for reduction of fresh water amount in each manufacturing process. One of recognized and viable emerging wastewater treatments in the scientifi c literature [1][2][3][4] is the advanced oxidation process (AOP) (or mineralization) of polluting compounds from wastewaters to carbon dioxides and/or other harmless species. A special attention was given for Fenton and/or Fenton-like oxidation processes applied for discoloration or dye removal purposes, together with its advantages (i.e. high effi ciency, short operating time, simplicity in destroying the contaminants, ...

Textile Wastewater Treatment in a Spinning Disc Reactor: Improved Performances—Experimental, Modeling and SVM Optimization

“…At the time of the experiments, the studied textile WW resulted from an indigene (Iasi, Romania) textile company that manufactures cotton fabrics colored from yellow to red (with a dyeing bath stuff formulation based on two azo dyes, Rosso Kemazol RB and Arancio Kemazol 3R, and Remapon FRD as binding agent) (textile wastewater characteristics presented in other reports) [24,25,31]. For the real textile wastewaters, certain performances were obtained by applying different treatment processes (e.g., adsorption on activated carbon or different 'low cost' adsorptive materials as sawdust, coal ashes, residual biomass; different advanced oxidative processes (AOPs) such as Fenton oxidation (FO) (Fe 2+ /H 2 O 2 ), catalytic wet peroxide oxidation (CWPO) (zeolites/metal oxides of transitional metal species-M n+ /H 2 O 2 ), photo-Fenton (photo-FO) (Fe 2+ /H 2 O 2 /UV) or Fenton-like oxidation (transitional/high valence metallic species-M n+ /H 2 O 2 ), photo-decomposition of hydrogen peroxide (H 2 O 2 /UV), photolysis of ozone (O 3 /UV), sonolysis, radiolytic treatment; coagulation-flocculation (CF) in association with sedimentation or filtration etc., individually or mixed applied [14,25], but not in the case of SD and FO technology, applied in the proposed mono-block experimental setup.…”

“…(A) (B) The overall Fenton oxidation process can be simplified as in Equation (2) [24,31]. The hydrogen peroxide concentration influence on the suspended solids removal, for the three textile effluent circulations through the laboratory SD setup is shown in Figure 7B.…”

“…Color determination. A standard method (SR ISO 7887/97) was used where the color is expressed by absorbance under the blank (distilled water) at three different wavelengths, i.e., 436, 525 and 620 nm; for industrial wastewaters, the absorbance at 436 nm is preferred [15,31,32]. Furthermore, the color can be expressed by the Hazen color index (i.e., an absorbance value of 0.069 at 456 nm corresponds to 50 Hazen units (HU)) [32].…”

Synergistic Effect of dark and photoreactions on the removal and photo-decolorization of azo carmosine dye (E122) as food dye using Rutile- TiO2 suspension

“…and then produces a peroxide radical HOO ., the last species can be reacted with hydrogen ion in an aqueous solution and produces hydrogen peroxide. Hydrogen peroxide in the presence of light will split to double hydroxyl radicals ions [61][62][63][64][65]. The most acceptance mechanism for decolorization of carmoisine was suggested in figure 8 [10].…”