Cracking of Polypropylene to Light Oil in Supercritical Water
Tetsuji MATSUI* and Masashi OHNISHI
Department of Applied Chemistry, Kobe City College of Technology; 8-3, Gakuen Higashimachi, Nishi-ku, Kobe-shi 651-2194 Japan
Dependence of decomposition of polypropylene in supercritical water on engineering parameters such as reaction temperature, reaction time, filling rate of water and amount of polypropylene was studied.
The results were as follows: (1) Reaction temperature was needed over 430 °C in order to attain the high decomposition. (2) The decomposition, the yield of oils and the evolved gas increased with increasing of reaction temperature and time. It was possible to reduce the gas evolution by lowering filling rate of water. (3) The effect of amount of polypropylene on the decomposition and the yield of oils was relatively low. (4) The gas chromatograms of oil products showed generation of various saturated and unsaturated hydrocarbons and aromatic hydrocarbons. Cracking of the hydrocarbons increased with reaction temperature and time to produce the light oil such as gasoline. (5) It was confirmed that gas products were hydrogen, methane, propane and butane, etc. (6) The effect of atmosphere on the component of the produced oil was little.