Deniz İzlen Çifçi

A review on pumice for water and wastewater treatment

AbstractPumice is a valuable scouring, scrubbing, and polishing material both in powdered form and as a pumice stone. It has been traditionally used in construction industry and biomedicine. It has been evaluated in recent years in the field of water, wastewater, and air treatment. The present study aimed to review the scientific literature of pumice stone with the particular focus on its use for the treatment of water and wastewater. It was observed that most of the publications from 1995 to 2015 dealt with construction materials and treatment use. A number of 143 papers published focused on the removal of cadmium, dyes, color, and many other pollutants by adsorption and catalytic oxidation, while 49% of the papers on water and wastewater treatment was dedicated on adsorption processes. Besides, pumice has been used as a filter medium and integrated to biological treatment. More recent publications have been focusing on integrating pumice with advanced oxidation processes (AOPs) after enrichment with oth...

Comparison of Fenton process and adsorption method for treatment of industrial container and drum cleaning industry wastewater

ABSTRACT The present study aims to explore the characterization of industrial container and drum cleaning (ICDC) industry wastewater and treatment alternatives of this wastewater using Fenton and adsorption processes. Wastewater derived from ICDC industry is usually treated by chemical coagulation and biological treatment in Turkey and then discharged in a centralized wastewater treatment facility. It is required that the wastewater COD is below 1500 mg/L to treat in a centralized wastewater treatment facility. The wastewater samples were characterized for parameters of pH, conductivity, COD, BOD5, TSS, NH3-N, TN, TOC, TP, Cd, Cr, Cu, Fe, Ni, Pb, Zn, and Hg. Initial COD values were in the range of 11,300–14,200 mg/L. The optimum conditions for Fenton treatment were 35–40 g/L for H2O2, 2–5 g/L for Fe2+, and 13–36 for H2O2/Fe2+ molar ratio. The optimum conditions of PAC doses and contact times in adsorption studies were 20–30 g/L and 5–12 h, respectively. Removal efficiencies of characterized parameters for the three samples were compared for both Fenton and adsorption processes under optimum conditions. The results suggest that these wastewaters are suitable for discharge to a centralized wastewater treatment plant.

Risk Evaluation of Seven Personal Care Detergents Based on Chemical and Ecotoxicological Characterization in Synthetic Aqueous Media

Personal care products (PCPs), composed of various chemicals as complex mixture nature, are evaluated among those MPs found often in treated sewage and greywater. Among PCPs, detergents (PCDs) are forming specific complex mixtures containing various endocrine disruptor chemicals, to be handled accurately. In this study, acute toxicity of seven PCDs including shampoos (4) and shower gels (3) collected from different Hotels located in different countries was investigated. Chemical characterization (Chemical oxygen demand, COD; Total organic carbon, TOC) was performed according to Standard Methods. Besides, absorbance spectrum of each PCD was screened using UV-vis instrument. Acute toxicity of synthetic solutions prepared by dissolving PCDs in distilled water was assessed on two freshwater crustaceans Daphnia magna (D. magna) and Ceriodaphnia dubia (C. dubia) according to ISO 6341 Method. Acute toxicity was assessed for 24 and 48 h of exposure time by dividing the number of immobile organisms by total tested organisms (20) to score immobilization percentiles of each sample tested. By this way it was possible to calculate the concentration of EC50indicating a 50% population immobilization, using PROBIT program. The results of chemical characterization showed that the biodegradability by means of TOC/COD ratio of PCDs was very low. C. dubia was observed to be more sensitive than D. magna regarding lower values of EC50. All tested chemicals were found to be harmful according to EC50 toxic chemicals evaluation scoring system.