The high concentration of oxygenated compounds in pyrolytic products prohibits the conversion of hemicellulose to important biofuels and chemicals via fast pyrolysis. Herein a dual-catalyst bed of CaO and HZSM-5 was developed to convert acids in the pyrolytic products of xylan to valuable hydrocarbons. Meanwhile, LLDPE was co-pyrolyzed with xylan to supplement hydrogen during the catalysis of HZSM-5. The results showed that CaO could effectively transform acids into ketones. A minimum yield of acids (2.74%) and a maximum yield of ketones (42.93%) were obtained at a catalyst to feedstock ratio of 2:1. The dual-catalyst bed dramatically increased the yield of aromatics. Moreover, hydrogen-rich fragments derived from LLDPE promoted the Diels-Alder reactions of furans and participated in the hydrocarbon pool reactions of non-furanic compounds. As a result, a higher yield of hydrocarbons was achieved. This study provides a fundamental for recovering energy and chemicals from pyrolysis of hemicellulose.

热解产物中的高浓度含氧化合物禁止半纤维素通过以下方式转化为重要的生物燃料和化学物质快速热解。本文开发了CaO和HZSM-5的双催化剂床，将木聚糖热解产物中的酸转化为有价值的碳氢化合物。同时，在HZSM-5催化过程中，LLDPE与木聚糖共热解以补充氢气。结果表明，CaO可以有效地将酸转化为酮。在催化剂与原料的比例为2：1时，酸的最低收率（2.74％）和酮的最大收率（42.93％）。双催化剂床极大地提高了芳烃的收率。此外，衍生自LLDPE的富氢片段促进了呋喃的Diels-Alder反应，并参与了非呋喃化合物的碳氢化合物库反应。结果，获得了更高的烃产率。