The Role of Organic Solvents in the Destruction of Metallic Copper
Purpose of reseach was to study the effect of the nature of the liquid phase solvent on the interaction of acetic acid with M1 copper and copper (II) acetate (0.5 mol / kg)in the presence of sodium hydroxide (0.6 mol/kg). Methods. Metal copper of the M1r brand was used in the form of plates of linear dimensions of 10 x 5 x 1 mm. the Experiment was carried out in laboratory conditions using a reaction cylindrical container with a volume of 600 ml and linear characteristics of 70 mm, H 170 mm And a high-speed paddle agitator with a rotation speed of 1560 rpm. a glass bead of the S1 type made of sodium-calcium-silicate glass with a diameter of 1.5 mm Was used. the loading Weight (excluding the metal copper plate) was 100 ± 2 g. Using the gravimetric method, kinetic studies were performed as a result of measuring the mass of the copper samples under study with an accuracy of up to the fourth sign (at least 3 measurements). The content of copper (II) compounds was determined using the direct titration method (indicator - starch solution; reagents - potassium iodide, saturated solution of potassium bromide, sodium thiosulfate). The method of direct titration with an alkali solution in the presence of a methyl orange indicator was used to determine the content of acetic acid. Electron microscopic studies were performed using the EOL 6610LV scanning electron microscope. Results. The influence of the nature of the liquid phase solvent on the interaction of acetic acid with M1r copper and copper (II) acetate (0.5 mol/kg) in the presence of sodium hydroxide (0.6 mol/kg) in the presence of fractional input of the last and initial concentration of 20% of the stoichiometric amount was Studied. It was Found that the process of metal destruction occurs when using organic solvents of various groups (alcohols, esters, hydrocarbons). The solubility of Cu(CH<sub>3</sub>COO)<sub>2</sub>·3Cu(OH)<sub>2</sub> in acidic solutions of solvents was evaluated and it was found that the highest solubility is inherent in 2-propanol, ethylene glycol, and white spirit. Conclusion. The degree of destruction of copper depends on the ability of the solvent to dissolve the hardly soluble product formed during the process-Cu (CH<sub>3</sub>COO)<sub>2</sub>·3Cu(OH)<sub>2</sub>, and therefore prevent the accumulation of surface deposits and destroy the latter, which leads to cleaning the metal surface from them. The most profound process of metal destruction occurred when using the liquid phase of white spirit, ethylene glycol and isopropyl alcohol as a solvent. The limiting stage of the process of destruction of metallic copper in the selected conditions is the removal of the product from the metal surface. The presence of glass beads in the system as a mechanical agent favors the intensification of the metal destruction process.