An aluminium fluorosensor for the early detection of micro-level alcoholate corrosion.

The detection of the dry alcoholate corrosion of aluminium is vital to design a corrosion resistive aluminium alloy for the storage and transportation of biofuel (methanol or ethanol). By synthesizing an Al fluorescent probe operable in an alcoholic medium, we quantified the alcoholate corrosion in terms of the fluorometrically estimated soluble alkoxide (Al(OR)) generation under nitrogen atmosphere. With time, a linear increase in corrosion with specific aluminium dissolution rate constants ∼2.0 and 0.9 μg per day per cm were estimated for aluminium and Al-7075 alloy, respectively. During open atmosphere monitoring, the adsorbed moisture converted small extent of Al(OR) to the insoluble Al(OH) at the alloy surface which retarded the alcoholate corrosion appreciably.