| 摘要 |
<p>PROBLEM TO BE SOLVED: To treat waste plastics by pyrolyzing them in the presence of a gallium-contg. silicate catalyst so as to afford a treated product useful as a chemical feedstock or the like in high yield and at low cost. SOLUTION: This treatment of waste plastics is performed as follows: melted waste plastics are pyrolyzed in the presence of a gallium-contg. silicate catalyst and the resulting product is recovered; wherein it is recommended, for example, that the above catalyst to be used is such one as to be prepared by converting, esp. a gallosilicate of the formula xM12O.yGa2O3.zSiO2.nH2O (M is Na, K or the like) to a proton-type by ion exchange followed by formation into granules each 0.2-5 mm in average size. More precisely, this treatment is recommendedly performed as follows: waste plastics are placed in a melting tank 1 and then melted under heating at 200-350 deg.C using a heater 4, the resulting melt is extruded into a reaction vessel 2 where the melt is brought into contact with the above catalyst in a catalyst bed 8.</p> |
