The field of my graduation work was study of different potentiometric titrations and their partial validation. I evaluated the purpose of the potentiometric titrations for different tehnological systems, mainly in the food processing industry (baking powder, baking soda, citric acid, eating vinegar, wine stone). I compared the results obtained by classical titration (manual titrations use a glass burette) and automatic titration and noted deviations and errors of determinations. The differencies between both methods as well as advantages and disadvantages of both titration methods were identified. As can be seen from the results, both titration methods reproduce the accurate and precise results, which are well comparable to each other. I would like to point out that both titration methods are suitable for laboratory samples (solutions of Hydrochloric acid (HCl), solutions Glacial acetic acid (CH3COOH), solution of Phosphoric acid (H3PO4), etc. In case of real samples, the better choice is automatic titration method because it determines the exact volume at the end-point.
It can be concluded that in case of known composition of samples, the best choice is classical titration (use a glass burette) due to the analysis speed, accuracy and costs. In case of diluted samples and unknown samples, it is better to use automatic titrations. If we have the samples which include mixtures of several acids, it will be very difficult from the titration curve to calculate the value of individual acid. According to the above-mentioned facts it can be concluded that for the samples which include mixtures of several acids, the correct choice of the method will be atomic emission spectroscopy.
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