The purpose of this Master’s thesis was to develop a method of analytical chemistry in order to identify and quantify the organic compounds found in strong aqueous solutions of nickel sulphate.

In the theoretical part of the thesis theoretical background of the work is discussed. Discussed subject areas are the development of analytical chemistry method, pre-treatment methods of the samples and the structure and function of the measurement instrumentation. In addition the determination of organic compounds from Bayer process solutions, which are used in production of aluminum oxide, is discussed. Determination of organic compounds from Bayer solutions is used as a comparison for the determination of organic compounds from process solutions of nickel sulphate.

In the experimental part of the thesis the practical methods for the determination of organic compounds from nickel sulphate solutions are presented. Identification of organic compounds was performed with gas chromatograph equipped with mass selective detector, and quantification of organic compounds was performed with gas chromatograph equipped with flame ionization detector.

37 organic compounds were identified from nickel sulphate solutions with at least 90 % similarity in comparation of mass spectra of the database (Wiley 8). Identified compounds were primarily alkanes and mono- and dicarboxylic acids with long hydrocarbon chains. Several types of phthalates were also identified.

Concentrations of organic compounds were determined with sufficient repeatability from six aliquots from 12 compounds in nickel sulphate solution A and 16 compounds from nickel sulphate solution B. In aliquots the relative standard deviations of retention times were 0,04-0,29 % (Solution A) and 0,03-0,57 % (Solution B). Relative standard deviations of the areas of chromatographic peaks were 9,0-46,0 % (Solution A) and 14,5-98,8 % (Solution B).

Total masses of the extracted organic compounds in nickel sulphate solutions were also determined. Determined concentrations of extracted organic compounds were 1,0 mg/L (Solution A) and 0,5 mg/L (Solution B). When comparing the concentrations of extracted organic compounds with the amounts of total organic carbon determined from solutions, the percentages of extracted organic compounds were 7,4 % (Solution A) and 5,3 % (Solution B).