Chemistry of Deicing Roads: Breaking the Bond between Ice and Road

Abstract

The rates for breaking the bond between ice and road surfaces are measured as a function of temperature, type of road surface, and chemical application. Surfaces of asphalt, concrete, and brick give indistinguishable results. Chemicals used include sodium chloride, calcium chloride, urea, and calcium magnesium acetate (CMA). The results are analyzed in terms of the maximum areas undercut and the rates at which the areas are undercut. The areas for all chemicals can be correlated with arguments based on freezing point depression. The rates seem consistent with diffusion controlled melting.