title: One-step hydroprocessing of fatty acids into renewable aromatic hydrocarbons over Ni/HZSM-5: insights into the major reaction pathways.
abstract: For high caloricity and stability in bio-aviation fuels, a certain content of aromatic hydrocarbons (AHCs, 8-25 wt%) is crucial. Fatty acids, obtained from waste or inedible oils, are a renewable and economic feedstock for AHC production. Considerable amounts of AHCs, up to 64.61 wt%, were produced through the one-step hydroprocessing of fatty acids over Ni/HZSM-5 catalysts. Hydrogenation, hydrocracking, and aromatization constituted the principal AHC formation processes. At a lower temperature, fatty acids were first hydrosaturated and then hydrodeoxygenated at metal sites to form long-chain hydrocarbons. Alternatively, the unsaturated fatty acids could be directly deoxygenated at acid sites without first being saturated. The long-chain hydrocarbons were cracked into gases such as ethane, propane, and C6-C8olefins over the catalysts' Brønsted acid sites; these underwent Diels-Alder reactions on the catalysts' Lewis acid sites to form AHCs. C6-C8olefins were determined as critical intermediates for AHC formation. As the Ni content in the catalyst increased, the Brønsted-acid site density was reduced due to coverage by the metal nanoparticles. Good performance was achieved with a loading of 10 wt% Ni, where the Ni nanoparticles exhibited a polyhedral morphology which exposed more active sites for aromatization.
authors.affiliation: Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China. lvpm@ms.giec.ac.cn yuanzh@ms.giec.ac.cn and Key Laboratory of Renewable Energy, Chinese Academy of Sciences, Guangzhou 510640, China and University of Chinese Academy of Sciences, Beijing 100049, China and Guangdong Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, China.
authors.forename: Shiyou
authors.initials: S
authors.lastname: Xing
authors.affiliation: Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China. lvpm@ms.giec.ac.cn yuanzh@ms.giec.ac.cn and Key Laboratory of Renewable Energy, Chinese Academy of Sciences, Guangzhou 510640, China and Guangdong Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, China and Collaborative Innovation Center of Biomass Energy, Zhengzhou 450002, Henan Province, China.
authors.forename: Pengmei
authors.identifier: http://orcid.org/0000-0001-9449-8652
authors.initials: P
authors.lastname: Lv
authors.affiliation: Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China. lvpm@ms.giec.ac.cn yuanzh@ms.giec.ac.cn and Nano Science and Technology Institute, University of Science & Technology of China, Suzhou 215123, China.
authors.forename: Jiayan
authors.initials: J
authors.lastname: Wang
authors.affiliation: Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China. lvpm@ms.giec.ac.cn yuanzh@ms.giec.ac.cn and Key Laboratory of Renewable Energy, Chinese Academy of Sciences, Guangzhou 510640, China and Guangdong Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, China.
authors.forename: Junying
authors.initials: J
authors.lastname: Fu
authors.affiliation: Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China. lvpm@ms.giec.ac.cn yuanzh@ms.giec.ac.cn and Key Laboratory of Renewable Energy, Chinese Academy of Sciences, Guangzhou 510640, China and University of Chinese Academy of Sciences, Beijing 100049, China and Guangdong Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, China.
authors.forename: Pei
authors.initials: P
authors.lastname: Fan
authors.affiliation: Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China. lvpm@ms.giec.ac.cn yuanzh@ms.giec.ac.cn and Key Laboratory of Renewable Energy, Chinese Academy of Sciences, Guangzhou 510640, China and Guangdong Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, China.
authors.forename: Lingmei
authors.initials: L
authors.lastname: Yang
authors.affiliation: Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China. lvpm@ms.giec.ac.cn yuanzh@ms.giec.ac.cn and Key Laboratory of Renewable Energy, Chinese Academy of Sciences, Guangzhou 510640, China and Guangdong Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, China.
authors.forename: Gaixiu
authors.initials: G
authors.lastname: Yang
authors.affiliation: Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China. lvpm@ms.giec.ac.cn yuanzh@ms.giec.ac.cn and Key Laboratory of Renewable Energy, Chinese Academy of Sciences, Guangzhou 510640, China and Guangdong Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, China and Collaborative Innovation Center of Biomass Energy, Zhengzhou 450002, Henan Province, China.
authors.forename: Zhenhong
authors.initials: Z
authors.lastname: Yuan
authors.affiliation: Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China. lvpm@ms.giec.ac.cn yuanzh@ms.giec.ac.cn and Key Laboratory of Renewable Energy, Chinese Academy of Sciences, Guangzhou 510640, China and Guangdong Key Laboratory of New and Renewable Energy Research and Development, Guangzhou 510640, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Chen