Combustion Products from the Incineration of Plastics,

Analysis of the combustion products of plastics was undertaken for three reasons to provide scientists and engineers with information needed to design incinerators in order to maximize their efficiency while minimizing maintenance and pollution, to identify products of incomplete combustion potentially recoverable for their fuel or crude chemical value and to identify products of incomplete combustion which would be acutely toxic in an accidental fire. Plastics studied were polyvinyl chloride, polysulfone, polyurethanes, polyimide, LopacR, BarexR, phenol formaldehyde, urea formaldehyde, polyethylene, polypropylene, polystyrene, polycarbonate, polyenylene oxide, polyester, synthetic fabrics DacronR, OrlonR, nylon, and natural products wood and wool. One- to three-gram samples were heated at a controlled rate from 5 to 50 Cmin in the presence of a measured flow of air or air plus oxygen. By this method plastics were never completely combusted to carbon dioxide and water, but rather generated large numbers of gaseous and condensed products. Additional gaseous products included straight-chain saturated and unsaturated hydrocarbons through hexane, aromatic hydrocarbons, hydrogen chloride, sulfur dioxide, cyanides, ammonia, and oxides of nitrogen. Liquefied fractions produced by most plastics were complex mixtures of 10 to 50 compounds, including heterocyclic and polycyclic hydrocarbons.