The investigation of determination of anions and cations from environmental and biological samples by conductivity-ion, spectrophotometric-ion and potentiometric-ion chromatographic hybrid systems

II ABSTRACT Ph.D. Thesis THE INVESTIGATION OF DETERMINATION OF ANIONS AND CATIONS FROM ENVIRONMENTAL AND BIOLOGICAL SAMPLES BY CONDUCTIVITY-ION, SPECTROPHOTOMETRIC-ION AND POTENTIOMETRIC-ION CHROMATOGRAPHIC HYBRID SYSTEMS MUTLU ŞAHIN Anadolu University Graduate School of Sciences Chemistry Program Supervisor: Assoc. Prof. Dr. Adnan ÖZCAN 2005, 202 pages In this study, the source of contamination of some inorganic anions and cations from environmental and biological samples was determined by ion chromatographic system. During the experimental studies, conductivity, spectrophotometric and two kinds of potentiometric detectors were used. Although the new designed electrodes to be sensitive for anions and cations were used as a potentiometric detector, the conductimetric and spectrophotometric detectors were commercially provided. While the analysis targeted of anions and cations were completely determined by conductivity detector, the part of anions was only determined directly spectrophotometric detector whereas cations were not determined by this method. The analysis of some of the single charge anions were able to carried out by PVC membrane type electrode as used the first type of potentiometric detector. The analysis of all of the single and double charge target cations and some of the single charge anions were carried out by using the second type of potentiometric detector, which was constructed from a polypyrrole conducting polymer electrode. The results of each three type of detectors were observed to agree well in the 95% confidence level. In addition to, the investigation of the adsorption of nitrate from aqueous solutions by using the natural sepiolite and modified-sepiolite was carried out for the development of application of the study. The calculated results indicate that both natural and surfactant-modified sepiolite are effective sorbents for the removal of nitrate anion from aqueous solution, however, the surfactant-modified sepiolite was more effective than the unmodified sepiolite in this respect. The maximum amount of nitrate ion adsorbed occurred at a pH value of 2.0. Keywords: Ion chromatography, Ion selective electrode, Conducting polymer, Adsorption, Sepiolite