Abstract The catalytic co-pyrolysis of torrefied poplar wood sawdust (TPW) and high-density polyethylene (HDPE) was investigated over hierarchical HZSM-5. Compared with raw PW/HDPE, the bio-oil yield from co-pyrolysis of TPW/HDPE decreased gradually while the quality of bio-oil was upgraded. With increasing torrefaction temperature from 220 to 280 °C, the amounts of acids, furans, and anhydrosugars in bio-oil were significantly reduced due to the removal of hemicellulose, whereas the production of phenols and alkenes were improved due to the enhanced hydrogen transfer reaction. In the catalytic co-pyrolysis, increasing torrefaction temperature caused an enhanced production of mono-aromatics as well as the selectivity of BTX (benzene, toluene, and xylene). Nevertheless, severe torrefaction (280 °C) lead to a rapid reduction of aromatic yield and selectivity due to the loss of cellulose. Compared to parent HZSM-5, hierarchical HZSM-5 treated with alkaline concentration (0.2–0.3 mol/L) favored the formation of mono-aromatics at the expense of polyaromatics. The maximum mono-aromatics yield of 71.75% was obtained during catalytic co-pyrolysis of 260-TPW/HDPE over 0.3-HZSM-5. The present work suggests that torrefaction pretreatment followed by the catalysis of hierarchical HZSM-5 is an efficient way to promote the production of valuable mono-aromatic hydrocarbons from biomass and plastic wastes.

中文翻译：

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用于单芳烃生产的分级 HZSM-5 上焙烧杨木和高密度聚乙烯的催化共热解

摘要 在分级 HZSM-5 上研究了焙烧杨木锯末 (TPW) 和高密度聚乙烯 (HDPE) 的催化共热解。与原料PW/HDPE相比，TPW/HDPE共热解生物油收率逐渐下降，生物油品质提升。随着烘焙温度从 220 °C 升高到 280 °C，由于去除了半纤维素，生物油中酸、呋喃和脱水糖的含量显着降低，而由于氢转移反应的增强，酚和烯烃的产量得到提高. 在催化共热解中，提高烘焙温度会增加单芳烃的产量以及 BTX（苯、甲苯和二甲苯）的选择性。尽管如此，由于纤维素的损失，严重的烘焙（280°C）导致芳烃产率和选择性迅速降低。与母体 HZSM-5 相比，用碱性浓度 (0.2-0.3 mol/L) 处理的分级 HZSM-5 有利于单芳烃的形成，而牺牲了多芳烃。在 260-TPW/HDPE 在 0.3-HZSM-5 上催化共热解过程中获得了 71.75% 的最大单芳烃产率。目前的工作表明，烘焙预处理和分级 HZSM-5 的催化是促进从生物质和塑料废物中生产有价值的单芳烃的有效方法。在 260-TPW/HDPE 在 0.3-HZSM-5 上催化共热解过程中获得了 71.75% 的最大单芳烃产率。目前的工作表明，烘焙预处理和分级 HZSM-5 的催化是促进从生物质和塑料废物中生产有价值的单芳烃的有效方法。在 260-TPW/HDPE 在 0.3-HZSM-5 上催化共热解过程中获得了 71.75% 的最大单芳烃产率。目前的工作表明，烘焙预处理和分级 HZSM-5 的催化是促进从生物质和塑料废物中生产有价值的单芳烃的有效方法。