ISSN:
1572-8838
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
,
Electrical Engineering, Measurement and Control Technology
Notes:
Abstract In certain organic solvents, notably alcohols (and in particular methanol), DSA-type anodes deteriorate rapidly under anodic conditions. The active RuO2-based layer is itself quite resistant to corrosion; however, rapid dissolution of the titanium support through pores and cracks in the active oxide coating, eventually results in detachment of the surface layer. A survey of the titanium dissolution reaction in methanol, and (to a lesser extent) other common solvents, is reported first. Reaction was quite rapid in methanolic solutions at low pH, almost negligible in solutions of high pH, and inhibited in the former case on addition of increasing quantities of water or sulphuric acid. In similar experiments with oxide-coated titanium, the rate of metal dissolution in acidified methanol was reduced by addition to TiO2 to the RuO2 layer, increasing the active oxide loading, increasing the water or acid content of the solvent, use of low oxide annealing temperature, and operating at low current density. If this type of anode is operated in anhydrous alcohol systems, the use of a noble metal, or noble metal clad titanium, support would be worth considering. Of the other non-alcoholic solvents investigated, acetonitrile and propylene carbonate appeared to be more resistant to oxidation than dimethyl formamide or dimethyl sulphoxide — no trace of titanium dissolution was observed with any of these solvents.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00617520
