Effects of hydrogen chloride on the pyrolysis of HDPE

• Main Authors: Liang,Yu, 梁祐
• Other Authors: Chang,Ching-Yuan;Wu,Chao-Hsiung
• Format: Others
• Language: zh-TW
• Published: 1996
• Online Access: http://ndltd.ncl.edu.tw/handle/82974968508400111468

碩士 === 國立臺灣大學 === 環境工程研究所 === 84 === The pyrolytic reaction of chlorinated plastics such as poly( vinyl chloride )(PVC) will realease hydrogen chloride. Hydrogen chloride released from the pyrolysis ,in turn, may affect the mechanism of the pyrolytic reaction. In this study, the pyrolysis of high density polyethylene (HDPE), being the principal component of plastics in the municipal solid waste (MSW) is carried out in the thermal gravimetric analysis (TGA) system containing HCl gas. When the concentrations of hydrogen chloride (CHCl) are between 0 and 500 ppmv, the curves of residual mass fraction for pyrolysis of HDPE are about the same. The influence of HCl is not obvious as CHCl<500 ppmv. When the values of CHCl are between 500 and 1000 ppmv, the curves of residual mass fraction of HDPE are influenced moving to the higher temperature region. This indicates that HCl inhibits the pyrolytic reaction of HDPE, resulting in the lower conversion of HDPE. Furthermore, as concentrations of HCl are between 1000 and 5000 ppmv, the curves of residual mass fraction are not different. The composition of products for the pyrolysis of HDPE in affected by the existence of HCl. On the condition of no HCl, the yields of gaseous and solid products are about 26.5 and 73.5 %, respectively. When the concentration of HCl is 1000 ppmv, the yields of gaseous and solid products are about 13.1 and 86.9%, respectively. Thus, hydrogen chloride affects the pyrolysis rate and the composition of products for the pyrolysis of HDPE. Its influence on the performance of pyrolysis of plastics should be taken into account for the design of pyrolytic system.