COMPREHENSIVE EXPERT RESEARCH ON SOLVENTS FOR FLEXOGRAPHY ON ETHANOL BASIS

Abstract

Application of gas chromatography allows obtaining basic data on the mixture composition, that is revealing the main component, discovering availability of impurities of macro- and microcomponents at qualitative and quantitative levels. It is possible to obtain data on the presence of moisture using IR spectroscopy. Quantitative parameters on the presence of water can be obtained using titration methods аccording to K. Fisher or using gas chromatography with a thermal conductivity detector. Density parameters and fraction composition allows revealing (indirectly) the presence of other impurities, as well as establish conformity of the object under research to requirements of the relevant normative and technical documentation. The obtained complex is sufficient for the formation of conclusions in categorical form and does not require additional data provided that the following signs are met, which include: 1. Presence of ethyl alcohol as the main component (usually more than 90 %). 2. Dehydration is one of the key indicators that allows the use of solvent for flexography. 3. Presence of components added to ethanol to provide the required volatility (eg, esters). 4. Low content of heavy (high boiling) components. The paper considers differences of solvents for flexography from other similar objects that can be important for expert research. Besides differences in the composition and properties of considered products, also the differences in the characteristics of the goods in the Ukrainian classification of goods of foreign economic activity are demonstrated. An example of use of data obtained as a result of chemical research, by an commodity expert in formulating categorical conclusions on delivered question is offered.