Determination of anions in geothermal waters with ion chromatography and bicarbonate with spectroscopic method

This thesis consists of two complimentary chapters. In the first part, simultaneous ion chromatographic analysis of seven different anions (Fluoride, Chloride, Nitride, Bromide, Nitrate, Phosphate, Sulfate) in real groundwater samples were performed by ion chromatography method. Some validation tests and the optimum conditions for the determination of anions were studied. Analysis of anions was performed by injection of samples to the chromatographic system after filtration and/or dilution. The precision and accuracy of the method were tested at three different concentration levels for each standard. Recovery studies were performed by adding standards in to the geothermal groundwater and drinking water samples. For groundwater samples recovery tests was performed between two successive months. Precision was also assessed as the percentage relative standard deviation (% RSD) of both repeatability (within-day) and reproducibility (between-day and different concentrations) for groundwater samples. SD and RSD values of 220 real groundwater samples acquired during 8 months were evaluated.In the second part, bicarbonate (HCO3-) analysis in groundwater samples was performed by spectrophotometric, titrimetric and potentiometric methods. New indicator dyes namely [N, N?-bis(4-dimethylaminobenzylidene)benzene?1,4-diamine (Y-10), 4-[4-(dimethylamino) phenylmethylene]amino acetophenone (Y-11) and 4-(4-(dimethylamino)phenyl)methyleneamino benzonitrile (Y?13)] were offered for absorption based analysis of HCO3- anion.The indicator dyes were characterized in the different solvents of ethanol (EtOH), dichloromethane (DCM), tetrahydrofurane (THF) and Toluene/Ethanol (To: EtOH) mixture (80:20)), in solid matrix of PVC and in Ionic Liquid media. Maximum absorption wavelength (?abs) and molar extinction coefficients (?) of the indicators were determined with Uv-Vis spectrophotometer in all of the employed matrices. Acidity constant values of three different indicator dyes were calculated in ethanol and polyvinylchloride for HCO3- sensing purposes. Cross sensitivities of the indicator dyes to other cations was also tested and evaluated.