Reaction control in radical-transforming catalytic degradation of polypropylene

For the purpose of chemical recycling of plastic wastes, catalytic degradation and liquefaction of Polypropylene (PP). subjected to high pressure H₂ was examined with a batch reactor. Iron supported active carbon (Fe/A.C.) acted to decrease solids and also increase liquid yield in condition of 673-693 K at H₂ pressure of 4.0 MPa (NTP) for 1 h. Compared with thermal degradation, liquid products became lighter because residue produced was degradated by the catalyst. Compared H₂ with Ar as reaction gas at 683 K, degradation of PP was promoted by H₂ in 0.5-1.0 h. In the results of the effect of H₂ pressure, degradation of PP was proceeded as the increase of H₂ under 3.0 MPa but was suppressed over 4.0 MPa. These results show that H₂ plays an important role in catalytic degradation of PP over Fe/A.C. catalyst.