Effects of metal oxides on the pyrolysis of poly(ethylene terephthalate)

• Published in: Journal of analytical and applied pyrolysis Vol. 73; no. 1; pp. 139 - 144
• Main Authors: Yoshioka, Toshiaki, Handa, Tomohiko, Grause, Guido, Lei, Zhigang, Inomata, Hiroshi, Mizoguchi, Tadaaki
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.03.2005
• Subjects: Benzene; Calcium hydroxide; Feedstock recycling; Iron(III) oxide; Nickel oxide; Poly(ethylene terephthalate) (PET); Pyrolysis; Titanium dioxide; Pyrolysis; Poly(ethylene terephthalate) (PET); Benzene; Feedstock recycling; Calcium hydroxide; Titanium dioxide; Nickel oxide; Iron(III) oxide
• ISSN: 0165-2370; 1873-250X
• DOI: 10.1016/j.jaap.2005.01.004

Metal oxides as Ca(OH) 2, NiO, Fe 2O 3 or TiO 2 showed different effects on the pyrolysis of PET. The experiments were carried out at 700 °C in a helium atmosphere using a laboratory equipment. Ca(OH) 2 led to the hydrolysis of the PET and the following decarboxylation of the resulting terephthalic acid to benzene in a high amount up to 31 wt.%. By this means a yield of 77% related to the terephthalic acid content in the PET. The addition of Fe 2O 3 led to a similar but weaker effect. Nickel oxide showed less influence on the pyrolysis products of PET. With titanium dioxide considerably less gaseous products were obtained. When a mixture of Ca(OH) 2 and NiO was used PET was converted to synthesis-gas with a high hydrogen and carbon monoxide content and a gas amount of about 70%. The experiments with mixtures of Fe 2O 3 or TiO 2 with Ca(OH) 2 showed little differences to the experiments with pure Ca(OH) 2.