Khoma R. Acid-base interaction of sulfur dioxide with amides aqueous solutions

Object of investigation: aqueous solutions of sulfur dioxide with formamide, acetamide, urea N-alkyl derivatives series. Aim of investigation: consists in a revealing of essence of physico-chemical processes at interaction of sulfur dioxide with formic, acetic and carbamic acids amides in aqueous solutions depending on temperature, a ligand structure and reagents concentrations. Methods of investigation: potentiometry, elementary analysis, spectroscopy (electron, IR, 1H, 13C NMR) and thermogravimetry, Theoretical and practical results: The main equilibriums are revealed during the studying of the acid-base interaction of sulfur dioxide with amides in water, and the models of complex formation processes in these systems are worked out. The formation of amides anionic complexes with hydrosulfite- and pyrosulfite- ions and molecular compounds of SO2 with amides in aqueous solutions is established. The method of separation of the contribution of hydrosulfite- and pyrosulfite-ions to the formation of anionic complexes in systems water - amide - sulfur dioxide based on the application of the potentiometry method with simultaneous fixation of potentials of platinum and glass electrodes towards silver-chloride one is offered. The technique by which for the first time the compound of molecular type of SO2 with carbamide has been synthesized from a aqueous solution is worked out. The prospects of the further studying of fungicide and bactericidal action of complex compounds of SO2 with carbamide in aqueous solutions is shown. These properties can be used for the suppression of plants diseases caused by fungi on crops of various agricultural plants. The results of the researches are used at delivering of special courses “Chemosorption methods of purification of exit gases of the industrial enterprises” and “Synthesis, structure and reactivity of coordination compounds” as individual sections. The antimicrobic properties of aqueous solutions of carbamide, containing complex compounds with SO2 are revealed.Degree of inculcation: the developed methods have been introduced into the practice of work of department of inorganic chemistry and chemical ecology (the individual parts of special course devoted to complex formation and physico-chemical investigation of coordination compounds. Field of application: inorganic chemistry.