POLYETHYLENE CONVERSION IN SUPERCRITICAL WATER

This paper describes pyrolysis of polyethylene (PE) and n-hexadecane ( nC16) in supercritical water (SCW). Batch reactions were conducted at temperatures ranging from 673 to 723 K, at a reaction time of 30 min, and water density between 0 and 0.42 g/cm(3). The pyrolysis rate of nC 16 in SCW was almost the same as that in 0.1 MPa argon (Ar) atmosphere . Product distribution was also more or less the same for both cases. PE pyrolysis results were clearly different from pyrolysis results in Ar. In SCW, higher yields of shorter chain hydrocarbons, higher 1-alke ne/n-alkane ratio, and higher conversion were obtained. This differenc e of PE pyrolysis in SCW and in Ar could be explained by considering t he difference in the reaction phase. (C) 1998 Elsevier Science B.V.