Application of response surface methodology in physicochemical removal of dyes from wastewater: A critical review.

Application of response surface methodology (RSM) for optimization of ammoniacal nitrogen removal from semi-aerobic landfill leachate using ion exchange resin

Organic dyes are used in a wide range of industrial applications (e.g., textiles, food products, cosmetics and pharmaceuticals), so they are frequently found in wastewaters and are increasingly becoming an environmental problem. This critical overview covers the most frequently used strategies for dye removal and the most common analytical techniques for monitoring these processes and identifying any intermediates generated. We also analyze experimental design strategies for optimizing removal processes. Finally, our concluding remarks include a future outlook for dye-removal processes and the analytical techniques employed.

An analytical overview of processes for removing organic dyes from wastewater effluents

Decolorization of Mordant red 73 azo dye in water using H2O2/UV and photo-Fenton treatment

Abstract In the past few years, there have been many researches on the use of different types of homogenous catalyst for the degradation of textile wastewater in conventional advanced oxidation processes (AOPs). However, homogenous AOPs suffer from few limitations, including large consumption of chemicals, acidic pH, high cost of hydrogen peroxide, generation of iron sludge, and necessity of post-treatment. Therefore, recently, there have been more researches that focus on improving the performance of conventional AOPs using heterogeneous catalysts such as titanium dioxide, nanomaterials, metal oxides, zeolite, hematite, goethite, magnetite, and activated carbon (AC). Besides, different supports such as AC that have been incorporated with transition metals and clays have been proven to have excellent catalytic activity in AOPs. This paper presents a comprehensive review of advances and prospects of catalytic AOPs for the decontamination of a wide range of synthetic and real textile wastewater. This review provides an up-to-date critical review of the information on the degradation of various textile dyes by a wide range of heterogeneous catalysts and adsorbents. The future challenges of AOPs, including chemical consumption, toxicity assessment, reactor design, and limitation of catalysts, are discussed in this paper. In addition, this paper also discusses the presence of ions, generation of by-products, and industrial applications of AOPs. Special emphasis is given to recent studies and large-scale combination of AOPs for wastewater treatment. This review paper concludes that more studies are needed for the kinetics, reactor design, and modeling of hybrid AOPs and the production of their corresponding intermediate products and secondary pollutants. A better economic model should also be developed to predict the cost of AOPs, as the treatment cost varies with dyes and textile effluents.

Recent advances and prospects of catalytic advanced oxidation process in treating textile effluents

Treatability of synthetic azo dye production wastewaters from Acid Blue 193 and Reactive Black 39 production and real Reactive Black 39 production effluent via Photo-Fenton-like process was investigated. Response surface methodology was employed to assess individual and interactive effects of critical process parameters (Fe 3+ , H 2 O 2 concentrations; initial chemical oxygen demand (COD) and reaction time) on treatment performance in terms of color, COD and total organic carbon (TOC) removal efficiencies. Optimized reaction conditions for synthetic AB 193 production wastewater were established as Fe 3+  = 1.5 mM; H 2 O 2  = 35 mM for CODs ≤ 200 mg/L and a reaction time of 45 min. Under these conditions, 98% color, 78% COD and 59% TOC removals were experimentally obtained and fitted the model predictions well. The same model also described the treatment of synthetic Reactive Black 39 production wastewater satisfactorily. Experimentally achieved removals were considerably lower than model predictions for real Reactive Black 39 production effluent due to its high chloride content.

Treatment of azo dye production wastewaters using Photo-Fenton-like advanced oxidation processes: Optimization by response surface methodology

Treatability of synthetic Acid Blue 193 and Reactive Black 39 production wastewaters and real Reactive Black 39 production effluent via photo-Fenton-like process was investigated. The Central Composite Design technique was used to study the effect of some critical process parameters of the photo-Fenton process (e.g. reaction time, initial COD and Fe(3+) : H(2)O(2) molar ratio) on synthetic Acid Blue 193 production wastewater treatment efficiency in terms of color, chemical oxygen demand (COD) and total organic carbon (TOC) removals. Selected process parameters were optimized to obtain maximum color, COD and TOC removal efficiencies. Optimum working conditions were established as 45 min reaction time and a Fe(3+) : H(2)O(2) molar ratio of 0.073 for wastewater having an initial COD (COD(o)) of 200 mg L(-1). Under these conditions, 99% color, 83% COD and 58% TOC abatements were experimentally obtained. In case of real Reactive Black 39 production effluent, photo-Fenton-like treatment efficiency was found to be considerably lower than that of the synthetic acid and reactive dye production wastewaters, which was attributable to the relatively high chloride (i.e. a well known OH radical scavenger) content of the real effluent.

https://link.springer.com/content/pdf/10.1039/b817423g.pdf

Optimization of the photo-Fenton-like process for real and synthetic azo dye production wastewater treatment using response surface methodology.

H2O2/UV-C treatment of the commercially important aryl sulfonates H-, K-, J-acid and Para base: assessment of photodegradation kinetics and products.

The high solubility, polarity and recalcitrant nature of naphthalene sulphonates render their treatment by conventional physicochemical and biological methods a rather difficult task. The present study aimed at investigating the treatability of a commercially important naphthalene sulphonate, e.g. H-acid, using H2O2/UV-C and Fe2+/H2O2/UV-C photochemical oxidation processes. The H2O2/UV-C process was capable of 100% H-acid, 48% COD and 27% TOC removals 180 min under the experimental conditions of 468 mg/l initial COD, 60 mM initial H2O2 concentration and an initial pH of 5.9–6.0. A steady increase in the average oxidation state throughout the photochemical reaction revealed that more oxidized organic intermediates were formed during H2O2/UV-C treatment of H-acid. The effect of initial H2O2 concentration on H2O2/UV-C treatment efficiency was examined by conducting experiments at varying initial H2O2 concentrations up to 200 mM. An initial H2O2 concentration of 150 mM appeared to be the optimum where the hig...

Gokce Tureli

Papers

Treatment of azo dye production wastewaters using Photo-Fenton-like advanced oxidation processes: Optimization by response surface methodology

Optimization of the photo-Fenton-like process for real and synthetic azo dye production wastewater treatment using response surface methodology.

H2O2/UV-C treatment of the commercially important aryl sulfonates H-, K-, J-acid and Para base: assessment of photodegradation kinetics and products.

H2O2/UV-C and Fe2+/H2O2/UV-C treatment of a commercial naphthalene sulphonate (H-acid)