Thermal and thermo-catalytic degradation of high-density polyethylene waste

✍ Scribed by N. Miskolczi; L. Bartha; G. Deák; B. Jóver; D. Kalló

• Publisher: Elsevier Science
• Year: 2004
• Tongue: English
• Weight: 482 KB
• Volume: 72
• Category: Article
• ISSN: 0165-2370
• DOI: 10.1016/j.jaap.2004.07.002

✦ Synopsis

Thermal and thermo-catalytic cracking behaviour of a commercial high-density polyethylene (HDPE) waste was investigated in the temperature range of 400-450 8C in a laboratory scale pyrex batch reactor. An equilibrium fluid catalytic cracking catalyst (FCC), HZSM-5 and a clinoptilolite containing rhyolite tuff were used as catalysts. The presence of a catalyst significantly altered both the yield and composition of the products and differences were found between catalysts having different acidities, micro-and macropore surface areas. The yield of gases increased in the order: non-thermo-catalytic cracking < clinoptilolite < FCC < HZSM-5 catalysed cracking, while the yields of liquid products increased in the sequence of non-thermo-catalytic cracking < clinoptilolite < HZSM-5 < FCC catalysed cracking. The catalysts significantly affected the isomerization of the olefin double bond and of the carbon-chain of the cracked products, the olefin content of liquids did not differ considerably. The effect of the catalysts on the yields and structure of products were getting less significant with increasing cracking temperature. The range of the carbon atom number in liquids was C 5 -C 28 in non-thermo-catalytic cases, whereas using catalysts it was C 5 -C 25 , but the temperature of cracking had a noticeable effect on the distribution of carbon atom. Each liquid fraction is of low sulphur content, which may be advantageous for application as fuel.