The anodic behaviors of nickel and molybdenum have been investigated in acid solutions, containing 1N or 6N chloride concentrations. The analysis of the anodic polarization curves shows the influence exerted by hydrogen ions and chlorides on the active dissolution of nickel and on the transpassive dissolution of molybdenum. From the determination of the electrochemical reaction orders, it appears that in 1N chloride solutions, the hydroxyl ions favor the dissolution of both metals, while in 6N chloride solutions hydrogen ions stimulate these processes, but only at the lowest tested pH values. As regards chloride ions, they are found to stimulate the dissolution of nickel, while they hinder the dissolution of molybdenum. The comparison with literature data permits to propose the dissolution reaction mechanisms of these two metals.
THE ANODIC-DISSOLUTION OF NICKEL AND MOLYBDENUM IN CONCENTRATED ACIDIC CHLORIDE SOLUTIONS
FRIGNANI, Alessandro;MONTICELLI, Cecilia;ZUCCHI, Fabrizio
1982
Abstract
The anodic behaviors of nickel and molybdenum have been investigated in acid solutions, containing 1N or 6N chloride concentrations. The analysis of the anodic polarization curves shows the influence exerted by hydrogen ions and chlorides on the active dissolution of nickel and on the transpassive dissolution of molybdenum. From the determination of the electrochemical reaction orders, it appears that in 1N chloride solutions, the hydroxyl ions favor the dissolution of both metals, while in 6N chloride solutions hydrogen ions stimulate these processes, but only at the lowest tested pH values. As regards chloride ions, they are found to stimulate the dissolution of nickel, while they hinder the dissolution of molybdenum. The comparison with literature data permits to propose the dissolution reaction mechanisms of these two metals.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
