FUEL
·
2018
·
IF 4.908
Min Zhang,Xian-Yong Wei,Zheng Yang,Dao-Guang Teng,Yan Xue,De-Wu Meng,Zhi-Min Zong
A highly active magnetic solid superbase (MSSB) was prepared by impregnating Mg 2 Si onto γ-Al 2 O 3 -coated ferroferric oxide nanoparticles via one-pot synthesis method and successfully applied in the catalytic hydroconversion (CHC) of the extraction residue (ER) from Naomaohu lignite. Large amounts of chain alkanes and arenes were detected in the soluble portion (SP) from the non-catalytic hydroconversion of the ER, while oxygen-containing organic compounds are predominant in the SP from the CHC of the ER, indicating that MSSB catalyzes the cleavage of C O bridged bonds in the ER. Oxybis(methylene)dibenzene was used as the lignite-related model compound to evaluate the catalytic activity of MSSB. The results show that MSSB facilitates heterolytically splitting H 2 to release H − and subsequent H − transfer, leading to the cleavage of C O bridged bonds.
研究领域:
化学工程
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Lin Hu,Jingcheng Wu,Xian-Yong Wei,Changlin Yu,Lei Li,Lingling Li
Exploring the value-added utilization of lignin showed the great significant to realize the efficient conversion of lignocellulosic biomass, which had good environmental, economic, and social benefits. However, the catalytic hydrogenolysis of lignin faced the great problems, including harsh reaction conditions and low product yield. In this research, the FeOx modified Ru/mordenite (M) was synthesized by deposition–precipitation method and strengthened the effective lignin conversion process. Ru 2.5% Fe 2.5% /M showed the high catalytic hydrogenolysis activity of β-O-4 and α-O-4 bond under the condition of 260 °C, 1 MPa H 2 , and 3 h in the methanol. Though the research about reaction of model compounds and several characterizations, synergistic action of highly dispersion RuFe nanoparticles and acidic sites significantly promoted the breakage of C-O bond. The introduction of Fe species can reduced the size of metal nanoparticles. The lignin oil reached the high value of 47.8 wt%, and contained the low RC value of phenolic compounds. Finally, the reaction mechanism of lignin catalytic hydrogenolysis was discussed, and it found that the highly dispersed RuFe nanoparticles enhanced the synergistic transfer ability of H 2 and methanol to release H•. This research would give some useful understandings for the efficient thermochemical conversion of lignin.
研究领域:
催化化学
·
生物质能
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
Joule
·
2019
·
IF 0
Man Yang,Haifeng Qi,Fei Liu,Yujing Ren,Xiaoli Pan,Leilei Zhang,Xiaoyan Liu,Hua Wang,Jifeng Pang,Mingyuan Zheng,Aiqin Wang,Tao Zhang
Cellulosic ethanol is one of the most important biofuels, yet its commercial production is hindered by the low-efficiency and high-cost bioconversion process. Here, we report a new chemocatalytic approach for the one-pot production of cellulosic ethanol. With a multifunctional Mo/Pt/WO x catalyst, cellulose is directly converted to ethanol in a one-pot reaction with a yield as high as 43.2 C%. Kinetic analysis reveals that such a one-pot process involves tandem catalysis from cellulose to ethylene glycol (rapid) followed by hydrogenolysis of ethylene glycol to ethanol (slow). Characterizations show that isolated and low-coordinated MoO x bonds to metallic Pt particles on the mesoporous WO x support, constituting x OMo–Pt–WO x interfacial sites, which offer high activity for C–O cleavage of ethylene glycol.
研究领域:
化学工程
·
可再生资源与环境科学
✓ 已验证
DOI
RENEWABLE ENERGY
·
2021
·
IF 8.001
Feng Lin,Yulong Ma,Yonggang Sun,Kanghe Zhao,Tingting Gao,Yingbo Zhu
Due to the inertness and structural complexity of lignin, upgrading lignin to biofuels and fine chemicals still faces great challenges. In this paper, a one-pot method was used to catalyze straw lignin with H-ZSM-5 supported by Ni and Ru bimetals, and the lignin conversion rate reached 88.1%. The yield of monophenol was 19.5%, of which the yield of 4-ethylphenol and 4-ethylguaiacol was 4.9% and 3.8%, respectively. The 2D HSQC NMR analysis confirmed that the Ni–Ru/H-ZSM-5 catalyst had an obvious activity of breaking C β -O bonds before and after the reaction. The result showed that after loading metal Ni and Ru, the Lewis acid of the catalytic system was greatly increased, which caused electron transfer between Ni and Ru. 3Ni-1.5Ru/H-ZSM-5 had the strongest activity due to the largest synergy among Ni, Ru and H-ZSM-5. The synergy was the key factor leading to the cleavage of C–C and C–O bonds in straw lignin and the high-performance catalytic degradation of lignin. Besides, the effect of reaction solvent and hydrogen resource on upgrading lignin to fine chemicals over 3Ni-1.5Ru/HZSM-5 catalyst was also intensively investigated. This research developed a method for the direct conversion of lignin into valuable monophenols.
研究领域:
催化化学
·
生物质转化
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2017
·
IF 4.601
Wei-Tu Li,Xian-Yong Wei,Xue-Ke Li,Xiang-Xue Liu,Zhan-Ku Li,Zhi-Min Zong
Catalysts Ni/γ-Al 2 O 3 , Mg 2 Si/γ-Al 2 O 3 , and Ni-Mg 2 Si/γ-Al 2 O 3 were prepared. Their activities for catalytic hydroconversions (CHCs) of some lignite-related model compounds were examined. For the CHCs of oxydibenzene (ODB), benzyloxybenzene, and oxybis(methylene)dibenzene, the suitable loadings of Ni and Mg 2 Si are 33 and 20% in Ni-Mg 2 Si/γ-Al 2 O 3 , respectively, and the optimal reaction conditions are 4 MPa of initial hydrogen pressure, 240 °C, and 2 h, under which ODB was almost completely converted to cyclohexane. The formation of possible intermediates during the CHC of ODB was discussed. Ni-Mg 2 Si/γ-Al 2 O 3 was proposed to have 3 functions, i.e., activating H 2 to biatomic active hydrogen (H⋯H), releasing H − , and heterolytically splitting H⋯H to release H − as well, resulting in the hydrogenation of aromatic rings and the hydrocracking of C O bonds, respectively.
研究领域:
化学工程
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
Small
·
2023
·
IF 13.3
Xin Guo,Xuening Sun,Jinfeng Zhang,Yuanfen Huang,Xiaohong Liu,Xin Liu,Weilin Xu,Dongzhi Chen
Silicon nanocrystals (SiNCs) have attracted extensive attention in many advanced applications due to silicon's high natural abundance, low toxicity, and impressive optical properties. However, these applications are mainly focused on fluorescent SiNCs, little attention is paid to SiNCs with room-temperature phosphorescence (RTP) and their relative applications, especially water-dispersed ones. Herein, this work presents water-dispersible RTP SiNCs (UA-SiNCs) and their optical applications. The UA-SiNCs with a uniform particle size of 2.8 nm are prepared by thermal hydrosilylation between hydrogen-terminated SiNCs (H-SiNCs) and 10-undecenoic acid (UA). Interestingly, the resultant UA-SiNCs can exhibit tunable long-lived RTP with an average lifetime of 0.85 s. The RTP feature of the UA-SiNCs is confirmed to the n—π* transitions of their surface C═O groups. Subsequently, new dual-modal emissive UA-SiNCs-based ink is fabricated by blending with sodium alginate (SA) as the binder. The customized anticounterfeiting labels are also prepared on cellulosic substrates by screen-printing technique. As expected, UA-SiNCs/SA ink exhibits excellent practicability in anticounterfeiting applications. These findings will trigger the rapid development of RTP SiNCs, envisioning enormous potential in future advanced applications such as high-level anti-counterfeiting, information encryption, and so forth.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Physical Chemistry Letters
·
2026
·Vol. 17
·期 27
·7770-7779
·
IF 4.5
Sun Tianjiao,Xu Shuting,Ma Jing,Yu Zhiwu
There
exist two pathways in the cleavage of ester bonds, R–(O═)C–O–C–R’,
which are central to polyester recycling and organic synthesis. Traditional
views emphasize electronic effects, where the more positively charged
carbon is considered the preferred site for nucleophilic attack, resulting
in the breaking of C acyl –O bond. However, halide
based ionic liquids were found to selectively cleave the C alkoxy –O bond of polyesters, a finding that cannot be rationalized
by charge considerations alone. In this work, we propose that it is
the presence of clusters in solutions that leverages the accessibility
of reactants and thus determines the reaction pathways. The idea has
been demonstrated in the study of a model binary system of methyl
benzoate (MB) and 1-butyl-3-methylimidazolium bromide ([BMIm]Br) using
excess infrared spectroscopy, molecular dynamics simulations, and
density functional theory calculations. Excess infrared spectroscopy
reveals seven distinct aggregate species in solution, including ionic
liquid-ester clusters and MB self-aggregates, providing direct experimental
evidence that the solution is microheterogeneous and that cluster
formation dictates the local reaction environment. In the catalytically
relevant cluster, [BMIm]Br(MB) 3 , DFT optimized geometries
show that the Br – ···C alkoxy distance (3.56 Å) is significantly shorter than the Br – ···C acyl distance (5.53 Å).
Molecular dynamics simulations confirm the preferential solvation
of C alkoxy around Br – . A potential energy
surface scan with respect to the Br – ···C
distance identifies a critical distance of approximately 3.5 Å
where the alkoxy C–O bond begins to deviate from equilibrium,
marking the incipient stage of partial bonding. At 2.34 Å, the
C alkoxy –O bond undergoes abrupt elongation, corresponding
to an energy maximum, showing a pattern of the transition state in
classic S N 2 reactions. These findings establish the proximity
effect, through cluster mediated spatial preorganization, as the governing
principle of C–O bond cleavage selectivity in ionic liquid-ester
systems.
✓ 已验证
DOI
PubMed
高影响因子
Materials Science and Engineering B-Advanced Functional Solid-State Materials
·
2023
·
IF 3.6
Yuchuan Ren,Zhanwei Xu,Ying Wang,Fanyu Lu,Yaze Zhao,Kai Yao,Hao Fu,Hao Luo
Applications of sodium ion batteries (SIBs) are inseparable from scalable anode materials with high electrical conductivity and excellent stability. In this work, coal tar pitch activated carbon was functionalized (FAC) and employed as a substrate, followed by a hydrothermal process to fabricate MoS 2 /FAC nanocomposite with tight bonding. The MoS 2 exhibits a homogeneous integrated structure with an enlarged interlayer spacing of 0.65 nm in the obtained MoS 2 /FAC. When employed as anode material for SIBs, the MoS 2 /FAC electrode delivers a promising reversible capacity of 174.0 mAh g −1 at 2 A g −1 , with a decay rate of 0.148%·cycle −1 after 500 cycles. The ultrahigh rate of sodium storage is mainly attributed to uniform MoS 2 nanosheets anchored on the FAC through C-O-Mo bonding, and the wide layer spacing of the ultrathin MoS 2 nanosheets.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
ChemCatChem
·
2016
·Vol. 8
·期 11
·1929-1936
·
IF 4.724
Bin Chen,Bin Zhang,Yibo Zhang,Xiangguang Yang
Graphical Save it for a Raney day : A series of Ag-modified Ni catalysts is prepared, and the role of bimetallic effects on the selective cleavage of C−O and C−C bonds is investigated in glycerol hydrogenolysis, a model reaction for the utilization of biomass-derived polyols. Compared to Raney Ni, the optimal Raney Ni 6 Ag catalyst is more active in glycerol conversion and efficient for C−O bond cleavage to afford a higher selectivity toward C 3 products. A series of Ag-modified Ni catalysts was prepared, and the role of bimetallic effects on the selective cleavage of C−O and C−C bonds was investigated in glycerol hydrogenolysis, a model reaction for the utilization of biomass-derived polyols. Compared to Raney Ni, the optimal Raney Ni 6 Ag catalyst was more active in glycerol conversion and efficient for C−O bond cleavage to afford a higher selectivity toward C 3 products (1,2-propanediol and lactic acid; 88 %) at the same ∼70 % conversion of glycerol, especially 1,2-propanediol (73 %). On Ni catalysts, the hydrogenation of adsorbed species was the most likely rate-limiting step in glycerol hydrogenolysis under alkaline conditions. The Ag additive enhanced the hydrogenation ability of Ni catalysts, which should be related to the higher strength of the adsorption of hydrogen and the lower strength of the adsorption of substrates on Ni sites because of the formation of Ni-Ag alloys. A mechanistic interpretation was presented for the excellent catalytic behavior.
研究领域:
催化化学
·
生物质利用
·
材料科学
✓ 已验证
DOI
高影响因子
ZEITSCHRIFT FUR ANORGANISCHE UND ALLGEMEINE CHEMIE
·
2022
·Vol. 649
·期 4
·e202200279
·
IF 1.414
Shuai-Cong Huo,Yao Li,Peng-Fei Ji,De-Xiang Zhang,Zhi-Jiao Zhang,Ying Yang,Herbert W. Roesky
Treatments of β -diketiminate aluminum dihydride LAlH 2 (L=HC[C(Me)N(Ar)] 2 , Ar=2,6- i Pr 2 C 6 H 3 ) with (2-chlorophenyl)methanol, 2,3-dimethylbutane-2,3-diol, 2,2-dimethylpropane-1,3-diol, 2,2-bis(bromomethyl)propane-1,3-diol, and p -diphenol resulted in the formation of compounds containing the C−O−Al−O−C linkages, including the acyclic LAl[( μ -O)CH 2 ( o -Cl−C 6 H 4 ) 2 ] 2 ( 1 ), the five-membered ring LAl[( μ -O)CMe 2 ] 2 ( 2 ), the six-membered ring LAl[( μ -O)CH 2 ] 2 CMe 2 ( 3 ) and LAl[( μ -O)CH 2 ] 2 C(CH 2 Br) 2 ( 4 ), and the macrocyclic [LAl( μ -O) 2 ( p -C 6 H 4 )] 4 ( 5 ), respectively. These practices prove that β -diketiminate aluminum dihydride is a valuable precursor for the preparation of acyclic and cyclic systems. 1 – 5 were characterized by melting point, 1 H and 13 C NMR, FT-IR, and single-crystal X-ray diffraction studies.
研究领域:
无机化学
·
材料化学
✓ 已验证
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2025
·
IF 4.7
Zehong Zhu,Qingxin Wu,Xueying Wang,Haiyang Zhang,Jian Li,Yanzhao Dong,Yongsheng Xu,Yunsheng Dai,Jinli Zhang
Here, the spiral mesoporous hydrothermal carbonaceous nanospheres (SMHNs) were designed and fabricated from pentose precursors to enhance gas diffusion in acetylene hydrochlorination. Through the optimization of hydrothermal conditions, the optimized SMCNs-800 material showcased the highest catalytic activity with an acetylene conversion of 77 % under the condition of GHSV (C 2 H 2 ) = 30 h −1 . The structural analysis indicated that the material with helical structure could provide larger pore sizes and abundant defect sites, exposing more active sites. The structure-activity relationship among acid-base properties of the catalyst surface, the adsorption-desorption capacity for the reactants and the catalytic activity jointly demonstrated that pyridine-N and -C=O could provide abundant basic sites for the adsorption and activation of H-Cl, thus accelerating the process of acetylene hydrochlorination reaction.
研究领域:
化学工程
·
材料科学
·
催化反应
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Zhongwei Wang,Xiangqian Chen,Yisheng Sun,Dongliang Hua,Shuangxia Yang,Laizhi Sun,Tianjin Li,Lei Chen
Designing highly active and stable catalysts for the selective cleavage of the C-O bond of lignin is important to convert it into high-valued aromatic compounds. Herein, a facile synthetic strategy was developed using melamine as a soft template to prepare a highly active catalyst consisting of highly dispersed Ni nanoparticles on defective N-doped carbon support. The results indicated that the decomposition of melamine during the pyrolysis process induced the nitrogen atoms into aromatic carbon. The introduction of N-doped carbon support acted as anchor points for the Ni nanoparticles, strengthening the metal-support interaction. Approximately 100 conversion of the representative lignin model compounds, including 2-phenylethyl phenyl ether, were converted into their aromatic monomers under mild conditions. The as-prepared catalyst was stable and reusable after five cycles with no apparent signs of deactivation. Moreover, the theoretical calculation revealed that N-doped carbon supported Ni-based catalyst possessed a lower activation energy of C-O bond than only carbon supported Ni-based catalyst for the C-O bond cleavage in hydrogenolysis of lignin and its model compounds.
研究领域:
催化化学
·
材料科学
·
能源化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）