Mustafa Karatas

Activation of pine cone using Fenton oxidation for Cd(II) and Pb(II) removal

This paper describes activation of pine cone with Fenton reagent and determines the removal of Cd(II) and Pb(II) ions from aqueous solution. Changes of the surface properties of adsorbent materials were determined by the FT-IR and SEM analysis after activation of pine cone. The effect of Fe(2+)/H(2)O(2) ratio, ORP, pH and contact time were determined. Different adsorption isotherms were also obtained using concentrations of heavy metal ions ranging from 0.1 to 150mgL(-1). The adsorption process follows pseudo-first-order reaction kinetics and follows the Langmuir adsorption isotherm. The study discusses thermodynamic parameters, including changes in Gibbs free energy, entropy, and enthalpy, for the adsorption of Cd(II) and Pb(II) on activated cone, and revealed that the adsorption process was spontaneous and exothermic under natural conditions. The maximum removal efficiencies were obtained as 91% and 89% at pH 7 with 90 and 105-min contact time for Cd(II) and Pb(II), respectively.

Removal of Pb(II) from water by natural zeolitic tuff: kinetics and thermodynamics.

The present study was aimed at examining the ability of a natural zeolitic volcanic tuff to remove Pb(II) ions from aqueous solutions under various conditions. The effects of various parameters such as optimum adsorbent mass, contact time, pH of the medium, Pb(II) concentration, and temperature were investigated. In addition, different adsorption isotherms were obtained using concentrations of Pb(II) ions ranging from 1mg/L to 200mg/L. The adsorption process follows second-order reaction kinetics and follows the Langmuir adsorption isotherm. The thermodynamic parameters are discussed in this article, including changes in Gibbs free energy, entropy, and enthalpy, for the adsorption of Pb(II) on tuff, and it is revealed that the adsorption process was spontaneous and exothermic under natural conditions. The maximum removal efficiency of 92% was obtained at a pH of 5 with a 25-min contact time for a 10 g/L solid-to-liquid ratio and an initial heavy metal concentration of 100mg/L.

Advanced oxidation of Reactive Blue 181 solution: a comparison between Fenton and Sono-Fenton process.

In this work, the decolorization of C.I. Reactive Blue 181 (RB181), an anthraquinone dye, by Ultrasound and Fe(2+) H2O2 processes was investigated. The effects of operating parameters, such as Fe(2+) dosage, H2O2 dosage, pH value, reaction time and temperature were examined. Process optimisation [pH, ferrous ion (Fe(2+)), hydrogen peroxide (H2O2), and reaction time], kinetic studies and their comparison were carried out for both of the processes. The Sono-Fenton process was performed by indirect sonication in an ultrasonic water bath, which was operated at a fixed 35-kHz frequency. The optimum conditions were determined as [Fe(2+)]=30 mg/L, [H2O2]=50 mg/L and pH=3 for the Fenton process and [Fe(2+)]=10 mg/L, [H2O2]=40 mg/L and pH=3 for the Sono-Fenton process. The colour removals were 88% and 93.5% by the Fenton and Sono-Fenton processes, respectively. The highest decolorization was achieved by the Sono-Fenton process because of the production of some oxidising agents as a result of sonication. The paper also discussed kinetic parameters. The decolorization kinetic of RB181 followed pseudo-second-order reaction (Fenton study) and Behnajady kinetics (Sono-Fenton study).

Nickel Adsorption on the Modified Pine Tree Materials

Removal of nickel ions from aqueous solutions containing 1-100 mg l−1, using pine tree (Pinus nigra) materials modified with HCl, was investigated on a laboratory scale. For this purpose, two natural adsorbents such as the modified pine bark (MPB) and the modified pine cone (MPC) materials with HCl solution were studied. At first, the required concentration level of the HCl solution for the modification was observed, and then this was followed by the determinations of optimum levels of adsorbent amount, stirring rate, contact time and pH values. Various adsorption isotherms were also obtained by using different concentrations of the heavy metal cations tested in the experiment. As a result, the maximum removal efficiency levels obtained were as follows; 97 % for the modified pine bark at pH 8 and 80 % for the modified pine cone at pH 8.

Effect of Mnso4 on the Chromium Removal from the Leather Industry Wastewater

Chromium (VI) is one of the heavy metals in water and wastewater that has the most toxic characteristic. Consequently, it is dangerous for human and environmental health. Various methods are used for removal of the chromium from wastewater, and new methods have been developed in recent years. Recent studies and investigations on the removal of environmental pollution selected methods that were economical, of optimum efficiently and could be carried out easily. In this study, the removal of Cr6+ in the leather industry wastewater is investigated using MnSO4 that was used easily and economically. Experimental studies are performed in two phases. In the first phase, the optimum MnSO4 dose for removal of Cr6+ was determined. In the second phase, the optimum pH was studied. About 96% removal of chromium was launched with 530 mg l−1 MnSO4 dose at pH value 9 in the wastewater sample.

Removal of Trichloroethylene (TCE) in up Flow Anaerobic Sludge Blanket Reactors (UASB)

ABSTRACT Low concentrations of chlorinated aliphatic compounds may be found in wastewater and contaminated soils from different industrial sources and in the air arising from these sources. Low levels of Volatile Organic Compounds (VOC)s can be removed by adsorption, incineration and biofiltration methods. These methods have some disadvantages, such as low removal efficiency or high operation costs. Chlorine has been removed from the chlorinated aliphatic compounds by anaerobic conditions. The aim of this research was the investigation of biological treatment of VOCs in high flow speed reactors. The resistance capacity of micro-organisms was investigated in an upflow anaerobic sludge blanket reactor (UASB) with automated control system, by feeding with co-substrate additions, by loading different ratios of organic matter, varying hydraulic retention time (HRT), maintaining stable concentrations of COD and Volatile Fatty Acids (VFA), pH, alkalinity, temperature (35°C) etc. during the anaerobic treatment. Glucose, sodium sulphate, calcium chloride, ammonium bicarbonate, potassium phosphate and methanol were used as the co-substrates. In these studies the removal rates of TCE were approximately 86.4–90.0%. The decomposition ratios were calculated for TCE as 0,231 mg g−1 VSS d−1. The highest methane ratio in the obtained biogas was 67.8% for TCE. Also, inhibition concentrations (IC) in 24 hours were determined as IC50; 31.1 and IC25; 9.9.

Cu(II) removal from aqueous solution by ureolytic mixed culture (UMC).

The study describes the sorption of living ureolytic mixed culture (UMC) to remove Cu(II) from aqueous solution under various conditions. The effects of various parameters such as optimum biomass, contact time, and Cu(II) concentrations on Cu(II) removal efficiency were investigated. The process was investigated using concentrations of Cu(II) ions ranging from 1 to 200 mg/L in equilibrium batch tests for Langmiur, D-R, and Freundlich isotherm models. The maximum removal efficiency of 99% was obtained a 1 g/L solid-to-liquid ratio with 1-min contact time for 100 mg/L initial concentration of Cu(II).