Thermochemical recycling of end-of-life and virgin HDPE: A pilot-scale study

被引：30

作者：

Abbas-Abadi, Mehrdad Seifali ^{[1
]}

Zayoud, Azd ^{[1
]}

Kusenberg, Marvin ^{[1
]}

Roosen, Martijn ^{[2
]}

Vermeire, Florence ^{[1
]}

Yazdani, Parviz ^{[1
]}

Van Waeyenberg, Jonathan ^{[3
]}

Eschenbacher, Andreas ^{[1
]}

Hernandez, Francisco Jose Arraez ^{[1
]}

Kuzmanovic, Maja ^{[1
]}

Thi, Hang Dao ^{[1
]}

Kresovic, Uros ^{[4
]}

Sels, Bert ^{[3
]}

Van Puyvelde, Peter ^{[5
]}

De Meester, Steven ^{[2
]}

Saeys, Mark ^{[1
]}

Van Geem, Kevin M. ^{[1
]}

机构：

[1] Univ Ghent, Fac Engn & Architecture, Dept Mat Text & Chem Engn, Lab Chem Technol LCT, B-9052 Zwijnaarde, Belgium

[2] Univ Ghent, Fac Biosci Engn, Dept Green Chem & Technol, Lab Circular Proc Engn LCPE, B-8500 Kortrijk, Belgium

[3] Katholieke Univ Leuven, Ctr Sustainable Catalysis & Engn CSCE, Dept Microbial & Mol Syst M2S, Fac Biosci Engn, Celestijnenlaan 200F, B-3001 Heverlee, Belgium

[4] Indaver NV, Dijle 17 a, B-2800 Heverlee, Belgium

[5] Katholieke Univ Leuven, Dept Chem Engn CIT, Fac Engn Sci, Soft Matter Rheol & Technol SMaRT, Celestijnenlaan 200J, B-3001 Heverlee, Belgium

来源：

JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS | 2022年 / 166卷

关键词：

Virgin and end-of-life HDPE; Pilot plant experimentation; Thermochemical recycling; Kinetic modeling; Two-dimensional GCxGC; Pyrolysis; HIGH-DENSITY POLYETHYLENE; PLASTIC WASTE; THERMAL-DEGRADATION; VOLATILE PRODUCTS; COKE FORMATION; LIGHT OLEFINS; HIGH-PRESSURE; PYROLYSIS; TEMPERATURE; CRACKING;

D O I：

10.1016/j.jaap.2022.105614

中图分类号：

O65 [分析化学];

学科分类号：

070302 ; 081704 ;

摘要：

Industrial-scale application of end-of-life plastic pyrolysis still faces significant problems, such as a lack of detailed knowledge on degradation mechanisms, parameters affecting the degradation, and formation pathways of the primary pyrolysis products. Today, the degradation mechanisms based on radical chain scission are insufficiently understood to explain the pyrolysis chemistry from feedstock-to-product comprehensively. In this study, the impact of operating conditions on the degradation mechanism is evaluated by pyrolyzing end-of-life and virgin high-density polyethylene (HDPE) in a continuous pilot-scale unit at temperature and pressure ranges of 450-504 degrees C and 0.1-2 bara. The pyrolysis products were analyzed based on the detailed product composition obtained using comprehensive two-dimensional gas chromatography (GCxGC). A simplified kinetic mechanism was proposed to describe the main production pathways of the various components by considering the weakest points along the polymer chain. The results showed that the chain-end scission mechanism is the main mechanism in the HDPE pyrolysis process, even at low temperatures and pressures in the studied ranges. The pyrolysis of virgin HDPE under sub-atmospheric pressure, 0.1 bara, at 464 degrees C reactor temperature, yields the highest concentration of linear hydrocarbons in the pyrolysis oil (93.2 wt%). At higher pressure and temperature, the cyclic and branched hydrocarbons had a higher share of up to 17.4 wt% compared to 6.8 wt% at vacuum pressure and lower temperature. Interestingly, the pyrolysis of end-of-life HDPE at atmospheric pressure and 450 degrees C led to more cyclic and branched hydrocarbons (sum: 22.1 wt%), as opposed to that of virgin HDPE which is more prone to the production of linear hydrocarbons at the studied conditions. Regarding the additives and contaminants, a large amount of different metals and halogen atoms in the ppm range were detected in end-of-life HDPE, of which a small amount was still found in the pyrolysis oil.

引用

页数：12

共 94 条

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