APPLIED CATALYSIS B-ENVIRONMENTAL
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2020
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IF 16.683
Shanhui Zhu,Huan Liu,Sen Wang,Xiaoqing Gao,Pengfei Wang,Jianguo Wang,Weibin Fan
One-step efficient conversion of cellulose into value-added γ-valerolactone (GVL) is of great interest because it not only integrates complex tandem reactions in one-step, but also does not need additional hydrogen sources. To achieve this goal, it is crucial to fabricate high-performance catalyst that can accelerate both hydrolysis of cellulose and further transformation of generated stoichiometric levulinic acid (LA) and formic acid (FA) into GVL. CoNi nanoparticles encapsulated in N-doped thin graphene shell gave GVL yield as high as 55.9 % at 200 °C combined with Ag + -exchanged heteropolyacid (AgPW). This composite catalyst is highly resistant to the corrosion of LA and FA, and hence shows high catalytic stability. LA-adsorption FTIR spectra and DFT calculations indicate that LA and FA can penetrate through shell graphene layers into core CoNi sites via cracks. Compared to H 2 , FA can much more rapidly reduce LA because of its low dissociation energy barrier and high dissociation rate.
研究领域:
化学工程
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催化
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材料科学
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生物化工
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2024
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IF 12.2
Bingyan Sun,Haifeng Xu,Tan Li,Wenjie Guan,Kaige Wang
Upcycling waste plastic into aromatics presents an attractive strategy to tackle both plastic pollution and energy challenges. However, previous studies often rely on high temperatures, precious metals, and have broad product distributions. In this study, we reported that a Ni/ZSM-5 bifunctional catalyst can directly convert polyethylene (PE) into methylated aromatics with high selectivity under mild conditions, while eliminating the requirement for hydrogen gas and solvents. The liquid yield could attain up to 70.3 %, and the aromatics yield could achieve up to 51.7 %. Over 78.4 % of the aromatics were methylated aromatics including toluene, xylene, and mesitylene. Polymer chains underwent dehydrogenation over Ni and the acid sites in ZSM-5, forming C C bonds. Certain of these bonds evolved into carbenium ions through the process of proton transfer at the acid sites. The optimization of Ni and acid sites enhanced the oligomerization, cyclization, and aromatization process. The extra mesopores created by Ni on the molecular sieve aid in the generation of aromatics. Furthermore, the Ni/ZSM-5 catalyst demonstrated the ability to convert typical commercial grades of PE plastic, such as gloves and bottles, into aromatics with a selectivity of up to 61.1 %. It offers an economically feasible and environmentally friendly upcycling avenue for the circular economy of plastics.
研究领域:
化学工程
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环境科学
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材料科学
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催化
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产品关联
DOI
PubMed
高影响因子
Nature Nanotechnology
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2023
·Vol. 18
·期 7
·772-779
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IF 38.3
Du Junjie,Zeng Lin,Yan Tao,Wang Chuanhao,Wang Menglin,Luo Lei,Wu Wenlong,Peng Zijun,Li Hongliang,Zeng Jie
Plastic pollution is a planetary threat that has been exacerbated by the COVID-19 pandemic due to the surge in medical waste, personal protective equipment and takeaway packaging. A socially sustainable and economically viable method for plastic recycling should not use consumable materials such as co-reactants or solvents. Here we report that Ru nanoparticles on zeolitic HZSM-5 catalyse the solvent- and hydrogen-free upcycling of high-density polyethylene into a separable distribution of linear (C 1 to C 6 ) and cyclic (C 7 to C 15 ) hydrocarbons. The valuable monocyclic hydrocarbons accounted for 60.3 mol% of the total yield. Based on mechanistic studies, the dehydrogenation of polymer chains to form C=C bonds occurs on both Ru sites and acid sites in HZSM-5, whereas carbenium ions are generated on the acid sites via the protonation of the C=C bonds. Accordingly, optimizing the Ru and acid sites promoted the cyclization process, which requires the simultaneous existence of a C=C bond and a carbenium ion on a molecular chain at an appropriate distance, providing high activity and cyclic hydrocarbon selectivity.
研究领域:
化学
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材料科学
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环境科学
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产品关联
DOI
PubMed
高影响因子
Journal of Energy Chemistry
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2023
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IF 13.1
Zhe-Hui Zhang,Xianyuan Wu,Xiaohong Ren,Zeming Rong,Zhuohua Sun,Katalin Barta,Tong-Qi Yuan
Transformation of lignin to valuable chemicals via sustainable pathways is recognized as one of the most efficient ways to explore its value and replace the nonrenewable petroleum resource. In this work, an environmental-friendly transfer hydrogenation process has been developed to convert lignin derived 2,6-dimethoxybenzoquinone to 1,4-cyclohexanediol. Compared with previous work under hydrogen pressure (30 bar), this process uses isopropanol as both solvent and hydrogen donor, which significantly simply the operation process. The core of this study is the design and preparation of Mn modified Raney Ni catalysts by ball milling process. A series of Raney NiMn catalysts with different ball milling time and Mn content were prepared and investigated. Characterizations by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM) and transmission electron microscope (TEM) etc. showed that NiMnAl alloy was formed during the ball milling process and then transformed to NiMn alloy after treatment by aqueous NaOH. After optimization, a yield as high as 86.1% could be achieved for 1,4-cyclohexanediol at 200 °C in only 1 h.
研究领域:
化学工程
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催化
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绿色化学
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可再生资源
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）