School of Agricultural Engineering and Food Science, Shandong University of Technology
Guangdong Provincial Key Laboratory of New and Renewable Energy Research and Development
Shandong Research Center of Engineering and Technology for Clean Energy, Shandong University of Technology

单环芳烃（Mono-aromatic hydrocarbons, MAHs）是有机化工重要的基础原料，木质素经催化热解可实现绿色MAHs的制取。然而木质素热解气组分复杂，易导致催化剂快速积炭失活，不利于单环芳烃的富集。采用Ni和Ga金属改性的多级孔分子筛（HZSM-5@Al-SBA-15）为催化剂，用于催化提质木质素热解气定向制取MAHs，并在固定床反应器上探究催化热解产物分布规律及催化剂积炭行为。结果表明，多级孔分子筛具有发达的孔道结构，可有效提升木质素热解气催化提质过程中的传质扩散性能，且金属元素和介孔层的引入调变了催化剂酸性分布。相比于HZSM-5催化热解，HS（78.63%）、Ga/HS（77.15%）和Ni-Ga/HS（72.44%）多级孔分子筛均提升了MAHs的相对含量，降低了多环芳烃的生成量，气体产物中CO2的含量增加，表明催化剂促进了脱羧反应的进行。此外，负载型多级孔分子筛催化剂对应的积炭量明显降低，分别为Ni/HS（7.79%）、Ga/HS（6.37%）和Ni-Ga/HS（6.63%），表明金属组分的引入提升了催化剂的抗积炭性能。因此，基于金属修饰/孔道优化的负载型多级孔分子筛可催化提质木质素热解气定向制取高品质芳烃。本研究可为木质素废弃物高值利用提供基础参考。

Mono-aromatic hydrocarbons (MAHs) are important basic raw materials for organic chemicals industry. Catalytic pyrolysis of lignin can produce MAHs. However, the complicated components of pyrolysis vapours can result in rapid coke deactivation of the catalyst and the lower yields of mono-aromatic hydrocarbons. The lignin pyrolysis vapours were upgraded to MAHs by Ni or Ga modified hierarchical zeolite (HZSM-5@Al-SBA-15). The distribution of catalytic pyrolysis products and the coke deposition behavior of catalysts were investigated in a fixed bed reactor. Results showed that the hierarchical zeolites had the developed pore structure, which could effectively improve the mass transfer and diffusion performance of lignin pyrolysis vapours. Moreover, the introduction of metal elements and mesoporous shell modulated the acidity distribution of the catalysts. Compared with the pure HZSM-5, the relative content of MAHs (78.63%), Ga/HS (77.15%) and Ni-Ga/HS (72.44%) were increased, and the content of poly-aromatic hydrocarbons was effectively inhibited. The content of CO2 in the gas products increased, indicating that the catalyst could promote the decarboxylation reaction. In addition, the content of coke deposition with supported hierarchical zeolite catalysts was significantly reduced, which were Ni/HS (7.79%), Ga/HS (6.37%) and Ni-Ga/HS (6.63%), respectively. This indicated that the introduction of metal components improved the anti-coke performance of the catalysts. Therefore, the supported hierarchical zeolite based on metal modification and pore optimization could upgrade the lignin pyrolysis vapours into high quality aromatic hydrocarbons. This study provides a basic reference for the high value utilization of lignin waste.

山东省自然科学基金（ZR2021QE132），国家自然科学基金（52176192，52130610）和广东省新能源和可再生能源研究开发与应用重点实验室（E239kf0701）资助

王绍庆, 韩瑜, 易维明, 李志合, 万震, 焦妍. 负载型多级孔分子筛催化热解木质素制取单环芳烃[J]. 燃料化学学报（中英文）, 2023, 51(8): 1096-1105.

WANG Shao-qing, HAN Yu, YI Wei-ming, LI Zhi-he, WAN Zhen, JIAO Yan. Catalytic pyrolysis of lignin for production of mono-aromatic hydrocarbons over supported hierarchical zeolite[J]. Journal of Fuel Chemistry and Technology, 2023, 51(8): 1096-1105.