نوع مقاله : مقاله پژوهشی
نویسندگان
1 گروه مهندسی موادو متالورژی- دانشگاه صنعتی همدان
2 گروه مهندسی مواد و متالورژی-دانشگاه صنعتی همدان-همدان-ایران
3 گروه مهندسی مواد و متالورژی - دانشگاه صنعتی همدان، همدان، ایران
چکیده
کلیدواژه‌ها
عنوان مقاله [English]
نویسندگان [English]
The effect of different additives on simultaneous electrochemical dissolution and precipitation of copper from brass scrap in H2SO4 solution with a constant current density (250 A/m2) and ambient temperature has been investigated. The additives included chloride ion (concentration of 1000 ppm), nitrate ion, iron (II) and ammonium. Thermodynamic calculations of the electrochemical dissolution process and dominant species in the presence and absence of additives were analyzed. The change in voltage and its percentage as well as the morphology of copper deposited on the cathode were investigated in the presence and absence of these additives. According to the results, with the increase in concentration of sulfuric acid, the amount of voltage required to provide the current density of 250 A/m2 decreases. The presence of chloride ions in electrolytes containing sulfuric acid with a concentration higher than 50 g/l increases the process voltage. Also, in the presence of chloride ion, cubic morphology is obtained. Nitrate ion, like chloride ion, in low concentrations of sulfuric acid causes a decrease in the copper reduction voltage in the cathode, and vice versa, in higher concentrations of sulfuric acid, an increase in voltage is observed. Also, by adding nitrate ion, an octahedral structure is created with preferential growth of {100} and {110} planes. The dissolution and electrochemical deposition of copper in the presence of iron (II) is associated with an increase in voltage and creates a completely disordered and dendritic structure. Adding ammonium ion to sulfuric acid increases the voltage required and creates a cubic structure.
کلیدواژه‌ها [English]
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