Randhawa, N S and Katiyar, P K and Hait, Jhumki and Jana, R K and Singh, K K and Mankhand, T R (2013) Anodic dissolution behaviour of tungsten carbide scraps in ammoniacal media. In: 17th Int. Conf. on non-ferrous Met. 2013, 5-6 July 2013, Ranchi (India).
|PDF - Accepted Version|
In the present paper, potentiodynamic studies of WC scrap have been carried out as these studies give better idea about the anodic dissolution behaviour of the scrap material for their recycling to recover metal values. However, it has been seen that anodic passivation retards the dissolution of the scrap and adversely affects the recovery of metals. To minimise the passivity and to increase the anodic dissolution, some chemicals are often used as additives. Two different electrolytes namely hydrochloric acid and aqueous ammonia at varying concentrations had been employed for the above studies. The additives citric acid and oxalic acid were added to the acidic electrolyte whereas ammonium chloride, ammonium carbonate, ammonium sulphate were added in different concentration to the ammoniacal electrolyte. The studies revealed that 2% citric acid in 1N HCl was the optimum to achieve maximum anodic dissolution (current) of WC scrap. On the other hand, 2% NH4Cl was found suitable to obtain maximum anodic dissolution (current) in the ammoniacal (1N) medium. The potentiodynamic studies were followed by the actual electrodissolution experiments in an electrolytic cell with the help of a rectifier. The W and Co were recovered as tungsten oxide and metallic chips, respectively.
|Item Type:||Conference or Workshop Item (Paper)|
|Uncontrolled Keywords:||Cobalt; Electrodissolution; Potentiodynamic studies; Tungsten carbide scrap; Tungsten oxide|
|Divisions:||Metal Extraction and Forming|
|Deposited By:||Dr. Navneet Singh Randhawa|
|Deposited On:||11 Dec 2015 10:21|
|Last Modified:||11 Dec 2015 10:38|
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