Deicing chemicals and their preparation from polysaccharide sources

Abstract

Deicing chemicals intended primarily for decing pavement such as roads, bridges, and runways are prepared from polysaccharide sources (e.g., waste products such as sawdust) by reaction at a pressure of less than 600 psi and a temperature less than 200.degree. C. with a treating agent comprising alkali metal carbonates or bicarbonates or a mixture thereof and excess oxygen in the presence of water followed by the removal of oxalate and the treating agent. The reaction produces a liquid or a liquid/solid reaction product wherein the liquid contains the deicing chemical and the solid comprises a valuable pulp by-product. Calcium oxide or calcium hydroxide may be added to reduce the pressure resulting from the formation of large amounts of carbon dioxide during the reaction process and to aid in the removal of any oxalic acid formed during the reaction process. The deicing chemicals are impure mixtures of alkali metal salts of lower carboxylic acids substantially free of the alkali metal salt of oxalic acid, carbonic acid and of other organic compounds. The deicing chemicals are intended to be a substitute for the inorganic chloride salts (e.g, sodium chloride) commonly used for deicing highways.