Nese Ertugay

Sonocatalytic degradation of Direct Blue 71 azo dye at the presence Zero-Valent Iron (ZVI)

AbstractThe sonocatalytic degradation of Direct Blue 71 (DB71) azo dye has been studied in the presence of low-frequency ultrasound (20 kHz). An initial concentration of 50 mg L−1 of dye, within the range of typical concentration in textile wastewaters, was used. Batch sorption studies were conducted to study the effects of various parameters such as Zero-Valent Iron (ZVI) dose, pH, and effect of different power levels (20, 55, and 95 W), on DB71 oxidation. Oxidation of DB71 with the assistance of ultrasound was enhanced with the increase in ZVI initial concentration and ultrasonic power, and with the decrease in pH. It was observed that the color removal efficiency was influenced by the solution H2O2 amount. Accordingly, removal of 91.2% color and 97.2% total organic carbon (TOC) of dye was achieved by applying the optimal operational parameters with 0.3 g L−1 of catalyst, 2.5 pH and 25°C, during 20 min. In hybrid study, the color removal yield of 100% was obtained by combination of US/ZVI/H2O2 at dyestu...

Investigation of pH effect by Fenton-like oxidation with ZVI in treatment of the landfill leachate

Abstract In this study, effect of pH by Fenton-like with zero-valent iron (ZVI) process, advanced oxidation process in the leachate treatment, was investigated. The effect of pH value on colour and COD removal from leachate was determined at five initial pH values, 2.0, 2.5, 3.0, 3.5 and 4.0 (ZVI = 0.05 g/L, H2O2 = 150 mg/L). The highest colour and COD yield were obtained at pH 2.0. The colour removal was 87.9% (in 620 nm wavelength) and the COD removal was 74%. Experimental data from COD degradation with the Fenton-like process were analysed by using the zero-, first-, second-order and BMG kinetic models.

Basic Violet 10 (BV10) removal from aqueous solutions using sawdust of Swietenia mahagoni (Mahogany trees): adsorbent characterization, adsorption isotherm, kinetics, and thermodynamic studies

AbstractIn this work, the adsorption potential of sawdust of Swietenia mahagoni to remove Basic Violet 10 (BV10) from aqueous solutions was investigated by batch adsorption system. The adsorbent was characterized by Fourier transform infrared spectrophotometer, scanning electron microscope, particle size distribution, and Brunauer, Emmett, and Teller methods. The effect of various experimental parameters such as pH, initial dye concentration, adsorbent concentration, and temperature on adsorption of BV10 was investigated. The optimum pH for BV10 adsorption was found to be 4.2. Equilibrium adsorption data were analyzed by the Langmuir, Freundlich, Temkin, and Scatchard isotherm models. The results show that the best fit was achieved with the Langmuir isotherm with a maximum adsorption capacity of 222.76 mg g−1 at 50°C. Pseudo-first-order, pseudo-second-order, intraparticle diffusion, and Elovich models were used to analyze the kinetic data obtained at different BV10 concentrations. The adsorption kinetic d...

The degradation of landfill leachate in the presence of different catalysts by sonolytic and sonocatalytic processes

ABSTRACT In the study, the degradation of landfill leachate by single ultrasound (sonolytic) and sonolytic combined with Fe2+ and TiO2 catalysts was carried out in laboratory conditions. The effect of pH and ultrasonic wave amplitude was also investigated in terms of color removal, total organic carbon (TOC) and chemical oxygen demand (COD) from leachate by the sonolytic degradation process. In this process, the color removal efficiency was recorded as 81.81% at 620 nm, pH = 2.0 and 70% wave amplitude. The sonocatalytic degradation of landfill leachate accompanied by different catalysts was studied by using the 70% wave amplitude at pH = 2.0 and room temperature for 20 min. The sonocatalytic degradation of leachate by using Fe2+ and TiO2 was found to be significantly higher than sonolytic degradation (p < 0.05). As the Fe2+ concentration increased from 1.0 to 3.0 mg/L, the COD and color removal of leachate significantly decreased (p < 0.05) from 50 to 35.7% and from 95.5 to 90.9%, respectively. The experimental data obtained from sonocatalytic degradation was analyzed using the Behnajady–Modirshahla–Ghanbery (BMG) kinetic models and found to be compatible. The results showed that the combination of catalyst and sonolysis was a highly effective way to remove color, COD and TOC from landfill leachate.

Sızıntı Suyundan Fenton-Benzeri Prosesi İle Kimyasal Oksijen İhtiyacı ve Renk Giderimine ZVI ve H2O2 Konsantrasyonlarının Etkisi

Sizinti sulari, kompleks yapilari ve yuksek kirletici konsantrasyonlarindan dolayi aritimi zor atik sulardir. Bu calismada; sizinti sularindan Fenton-benzeri oksidasyon ile renk ve kimyasal oksijen ihtiyaci (KOI) giderimi calisilmistir. Renk ve KOI giderimine sifir degerlikli demir (ZVI) ve H 2 O 2 konsantrasyonunun etkisi incelenmistir. Renk giderimi 436, 525 ve 620 nm olmak uzere farkli uc dalga boyunda degerlendirilmistir. En yuksek KOI (%74.4) ve renk giderimi (436 nm’de %71, 525 nm’de %80.3 ve 620 nm’de %87.9) 0.05 g/L ZVI konsantasyonunda belirlenmistir. 200 mg/L H 2 O 2 konsantrasyonuna kadar artan H 2 O 2 konsantrasyonu ile renk ve KOI gideriminin de arttigi gozlenmistir. Optimum degerler; 20 dakikalik bir reaksiyon suresinde ve pH=2.0’de ZVI=0.05 g/L, H 2 O 2 =150 mg/L olarak bulunmustur. Ulasilan optimum sartlarda toplam organik karbon (TOK) giderimi %50 civarinda belirlenmistir.

The removal of COD and color by Fenton oxidation from leachate of Erzurum municipal solid waste landfill

The optimal conditions for treatment of leachate were determined as pH = 2.5, Fe2+= 2 mg/L and H2O2= 100 mg/L. Under the optimal conditions, approximately 90% color (at 620 nm), 84% color (at 525 nm), 74% color (at 436 nm) and 47.8% COD removal efficiency from leachate were achieved after 20 min of reaction. Depending on the results obtained experiments, Fenton process has been used successfully in removal of COD and color in landfill leachate.

Color and COD Removal of Azo Dye ‘Basic Blue 9’ by Fenton Oxidation Process: Determined of Optimal Parameters and Kinetic Study

Abstract Advanced oxidation of an azo dye, Basic Blue 9 (BB9) by Fenton oxidation was investigated in batch experiments. The UV-vis spectral changes of in aqueous solution during Fenton process were studied. It was easier to destruct the azo linkage group than to destruct the aromatic rings of (BB9) by Fenton process. The effects of different reaction parameters such as initial ferrous concentration, initial hydrogen peroxide (H2O2) concentration, initial pH, the initial (BB9) concentration and the temperature on the oxidative degradation of (BB9) have been assessed. The optimal reacting conditions for the color and COD removal were determined and it was found to be initial pH = 3.0, H2O2 = 100 mgL-1, Fe2+ = 3 mgL-1 at 20 °C temperature for 100 mgL-1 initial dye concentration. pH is highly effective parameter of color and COD removal in this work. Under optimal conditions, 100% color and 91% COD efficiencies of dye in aqueous solution were achieved within 20 min reaction time. The color removal kinetic of azo dye, (BB9), has also been investigated in the different H2O2 concentration. Kinetic data were studied using Behnajady-Modirshahla-Ghanbery model for color removal. It has been found that experimental kinetic data are represented well by Behnajady-Modirshahla-Ghanbery kinetic.