FUEL PROCESSING TECHNOLOGY
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2023
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IF 7.5
Xin Zhang,Jingyun Jiang,Hao Li
Hydrodeoxygenation (HDO) of bio-oils obtained by rapid pyrolysis of biomass into high value-added chemicals generally required harsh conditions. Herein, three kinds of mixed-phase ZrO 2 supports (denoted as ZSX, X = 2–4) with different crystal structure proportions were prepared by one-pot hydrothermal synthesis method, and their performance on the properties of Pd/ZrO 2 catalysts were investigated for vanillin HDO. Pd/ZS3 exhibited excellent efficiency in HDO of vanillin, a typical model compound of lignin, achieving approximately 100% yield of 2-methoxy-4-methylphenol (MMP) in presence of n-butanol as solvent and polymethyl hydrogen siloxane (PMHS) as hydrogen donor under mild conditions (35 °C, 1 h). It was due to catalytic synergy of exposed metal active sites, oxygen vacancies (O v ) and acid sites to occur electron transfer and enhance interaction between Pd and ZrO 2 . By tuning the crystal structure of ZrO 2 support, the influence of O v and acid sites of Pd/ZrO 2 over vanillin HDO performance was investigated, Pd/ZS2 with abundant O v and Pd/ZS4 with substantial acid sites promoted hydrogenation and hydrogenolysis , respectively, Pd/ZS3 possessed preferable conversion and selectivity as having the properties of both at once. Additionally, reaction pathway was also proposed in which vanillin was converted to MMP by combining intermediate of 4-hydroxy-methyl-2-methoxyphenol (HMP) with active hydrogen species while removing water. This developed catalysts with different crystalline highlighted an enormous promise for HDO of bio-oils into green fuel under mild conditions.
研究领域:
催化
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化学工程
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绿色化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
REACTIVE & FUNCTIONAL POLYMERS
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2019
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IF 3.074
Xing Yang,Yayun Zheng,Lan Wang,Qingping Guo,Haiquan Shan,Zongxiang Xu,Jujie Luo
This work involves the preparation and characterization of poly(styrene-b-isoprene-b-styrene)-poly(dimethylsiloxane- co -methylhydrosiloxane) (SIS-c-PDMS-co-PMHS) crosslinked membranes towards CH 4 /N 2 separation. SIS-c-PDMS-co-PMHS was synthesized via a simple hydrosilylation reaction with various PDMS-co-PMHS contents. The structure of crosslinked membranes was investigated by Fourier transform infrared spectroscopy , indicating the degree of hydrosilylation reaction. The morphology of sample membranes was observed in detail by means of Scanning Electron Microscope analysis . Thermodynamic stability and the crosslinked behavior of crosslinked membranes were explored by thermogravimetric analysis and Soxhlet extraction experiments. Furthermore, single gas (CH 4 , N 2 ) permeability was measured using the time-lag method. The CH 4 permeability of crosslinked membranes with 70 wt% PDMS-co-PMHS could reach 503 Barrer at 25 °C and 1 bar, which is significantly greater than that of SIS (25.9 Barrer), while the CH 4 /N 2 ideal selectivity hardly changed. Notably, CH 4 permeability further improved by 77.6% (893.4 Barrer) as the temperature increased to 55 °C. For the CH 4 /N 2 (50/50 vol%) mixed gas, the SIS-c-PDMS-co-PMHS-70 sample membrane exhibited ideal gas separation performance relative to that of the pure SIS membrane (CH 4 : 447.4 vs. 24.2 Barrer，N 2 : 188.1 vs. 9.46 Barrer).
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2022
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IF 10.53
Xiangshang Chen,Zhenjie Ma,Xihua Ren,Yue Jia,Huayan Chen,Xiaolong Lu
A novel and efficiently anchored 3-dimensional network extracting membrane (3D-NEM) with a thin functional surface layer comprising extraction carrier Bis(2-ethylhexyl) phosphate (D2EHPA) for nickel extraction was designed and studied in this paper. The active sites on the supporting Polytetrafluoroethylene (PTFE) hydrophilic ultrafiltration membrane were introduced by treating PTFE surface with potassium permanganate. Polydimethylsiloxane (PDMS) and Polymethylhydrosiloxane (PMHS) were applied to prepare a 3D network layer which is tightly anchored to the PTFE surface by introducing a crosslinking agent vinyltriethoxysilane (VTES). The prepared 3D-NEM was characterized by SEM, EDS, ATR-IR, XPS and etc. The influence of preparation parameters of 3D-NEM was studied and compared systematically. The optimum preparation conditions of 3D-NEM were based on a PDMS/PMHS/VTES ratio of 2:1:0.1 and a total polysiloxane concentration of 8 wt%. The operation stability test confirmed the average flux of the 3D-NEM in 72h reached 1871.16 mg·m -2 ·h -1 , and only 14.42% flux declined at the end of operation. The proposed designed 3D network structure produced a 5.5 μm-functional extracting layer which has benefits in both effective fixing of D2EHPA and tight anchor to the supporting surface. This work has dual advantages in improving flux and reducing extractant loss compared to supported liquid membrane (SLM) and polymer inclusion membrane (PIM) processes.
研究领域:
材料科学
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化学工程
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环境科学
✓ 已验证
DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
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2024
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IF 6.5
Ruixing Gu,Xiao Li,Hao-Yang Mi,Jian Han,Chongzhao Zhang,Chuntai Liu,Changyu Shen
Silicone coatings with anti-smudge, anti-fingerprint, abrasion resistance, and ultraviolet (UV) resistance properties are increasingly demanded for touch screens as the development of artificial intelligence and human-computer interaction interfaces. Herein, a transparent, robust, and self-cleaning silicone coating was developed by incorporating cage-like structures and long carbon chains into a 3D cross-linked network via the rational combination of polymethylhydrosiloxane (PMHS), PSS-Octavinyl substituted (VPOSS), lauryl acrylate (LA), and 1,2-epoxy-4-vinylcyclohexane (EVCH) through hydrosilylation reaction with the presence of Karstedt catalysts. After introducing sealed diphenyliodonium phosphate (I-200), the silicone coating (PVLE-I-200) demonstrated excellent pencil hardness, anti-smudge, and abrasion resistance, and its average transmittance of visible light reached about 92 %. Owing to the low surface energy carbon chains, the coating showed amphiphobic properties and excellent anti-fingerprint property. The binding between cyclohexyl epoxy and glass substrate contributed to the high adhesion of the coating, which remained nearly intact and slightly reduced surface wettability after 500 friction cycles of sandpaper. In addition, the PVLE-I-200 coating demonstrated UV resistance which could withstand 200 h of UV irradiation attributed to the cage-like structure of VPOSS. The functional silicone coating provides insights into the development of environmentally friendly coatings for touch screens with high transparency, abrasion resistance, anti-smudge, and anti-fingerprint properties.
研究领域:
材料科学
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化学工程
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表面涂层
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聚合物化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）