BIORESOURCE TECHNOLOGY
·
2021
·
IF 9.642
Yue Han,Chao Liu,Xiangchen Kong,Xing Wang,Yuyang Fan,Ming Lei,Ming Li,Rui Xiao,Longlong Ma
In this study, two counterexamples of lignin preoxidation-hydroconversion were reported. First, two lignin feedstocks were preoxidized with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) in acetonitrile with various dosages (15%, 30%, and 60%). Then, these preoxidized lignins (HELOs and MWLOs) were hydroconverted in supercritical ethanol catalyzed by Cu/CuMgAlO x . Total yields from HELOs were all higher than those from HEL , indicating the good promotion of DDQ preoxidation on the subsequent hydroconversion of HELOs, especially with the DDQ dosage of 15%. Differently, the promotion effect of DDQ preoxidation on the hydroconversion of MWLOs depended on the DDQ dosage as well as the reaction time. Through the comparison of two counterexamples, this work bursted the myth that preoxidation can always promote the subsequent hydroconversion of lignin, revealed the influence of lignin property, preoxidation degree, and reaction conditions on the subsequent hydroconversion of preoxidized lignin, and presented the new insight into the preoxidation-hydroconversion strategy for lignin.
研究领域:
化学工程
·
催化
·
木质素化学
✓ 已验证
DOI
PubMed
高影响因子
FUEL
·
2025
·
IF 7.5
Hong-Hui Gong,Xian-Yong Wei,Wen-Long Mo,Zhi-Min Zong,Guang-Hui Liu,Pei Liu,Kun-Peng Jiao
NiCs/Al 2 O 3 with medium-strong alkaline and the contents of Ni and Cs of 26.55 wt% and 0.02 wt%, respectively, was prepared by a three-step method and characterized with multiple tools. Oxydibenzene (ODB) and benzyloxybenzene (BOB) were used as low-rank coal-related model compounds and their catalytic hydroconversion (CHC) were investigated over NiCs/Al 2 O 3. Under mild conditions (MCs), NiCs/Al 2 O 3 can effectively activate H 2 to biatomic active hydrogen (H···H) and part of H···H can be effectively split to relative mobile H - and immobile H + on the NiCs/Al 2 O 3 surface. Both ODB and BOB can be completely converted and full hydrogenation (FH) of the benzene ring (BR) in −O-BR is the first step for the CHC of both ODB and BOB via H···H transfer to the BR under MCs. Subsequently, H - transfer to an ipso -carbon (IC) in the resulting oxydicyclohexane from the FH of ODB cleaves an −O-CH< bond to produce cyclohexane (CH I ) and cyclohexyloxy anion (CHOA), which abstracts H + from H···H to afford cyclohexanol (CH II ) followed by H - transfer to the IC in CH II and subsequent HO – release to yield CH I . As a result, CH I is the only final product from the CHC of ODB. In contrast, H - transfer preferentially proceeds to the carbon atom in the –CH 2 - of the resulting benzyloxycyclohexane from the FH of the BR in −O-BR of BOB to produce toluene and CHOA followed by the FH of toluene to get methylcyclohexane and the H + abstraction by CHOA from H···H to obtain CH II . Moreover, NiCs/Al 2 O 3 shows a distinguished recyclability and repeatability.
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
FUEL
·
2023
·
IF 7.4
Guang-Hui Liu,Yong-Chao Qi,Han Wang,Ai-Min Wang,Yu-Hong Kang,Yong Gao,Ni Bai,Zhan-Ku Li,Xian-Yong Wei
This paper focused on the complementary advantages of density functional theory (DFT) calculation and catalytic reaction regulation. Based on the effective identification of intermediates, the possible catalytic hydroconversion (CHC) pathways of lignite-derived aryl ethers over Ni/mordenite were discussed. Bond dissociation energy (BDE) calculations of >C–O– bonds in different substrates and intermediates show that BDEs of >C ar –O– bonds are generally higher than those of >C al –O– bonds, and there is obvious electron aggregation near O atoms. Mulliken charge distribution analyses of different atomic sites further revealed the possible adsorption sites of active hydrogen, especially H · and H + . Possible cleavage pathways were further speculated by evaluating the stability of different leaving groups. In the early stage of CHC, aromatic ring hydrogenation and >C al –O– bond cleavage dominate, rather than >C ar –O– bond cleavage. Enthalpy change analyses combined with the CHC of real substrates further indicate that lowering temperature is beneficial to the cleavage of >C ar –O– bonds under the premise of inhibiting H ··· H transfer and obtaining H · effectively. Appropriately increasing the support acidity to ensure sufficient H + release is conducive to >C al –O– bond cleavage, especially direct dehydroxylation/dehydration. The analysis of synergetic transfer pathways of active hydrogen during the CHC provides theoretical guidance for the pathway optimization of converting lignite into high-quality clean liquid fuels.
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
FUEL
·
2018
·
IF 4.908
Qing-Qing Teng,Xian-Yong Wei,Yi-Bing Sun,Sheng-Kang Wang,Jing-Hui Lv,Zhan-Ku Li,Zhong-Qiu Liu,Zhi-Min Zong
Catalysts trifloromethanesulfonic acid (TFMSA)/treated attapulgite powder (TAP), Ni/TAP, and Ni-TFMSA/TAP with different Ni and TFMSA loadings were prepared. The typical catalysts were characterized with multiple instruments and used for catalyzing hydroconversion of di(1-naphthyl)methane (DNM), which was used as a coal-related model compound. The suitable loadings of Ni and TFMSA in Ni-TFMSA/TAP were determined to be 28.6% of Ni and 33% of TFMSA. Under optimal reaction conditions of 5 MPa of initial hydrogen pressure, 240 °C, and 4 h over Ni-TFMSA/TAP, DNM was completely converted, producing decalin and 1-methyldecalin as the main products. The result suggests that Ni-TFMSA/TAP is highly active for both cleaving the C ar -C alk bond in DNM and hydrogenating the resulting naphthalene and 1-methylnaphthalene under mild conditions. Based on the identification of reaction products, the catalytic mechanism for DNM hydroconversion was discussed.
研究领域:
催化化学
·
能源化学
✓ 已验证
DOI
高影响因子
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
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2022
·
IF 7.139
Ming Su,Huihu Wang,Huang Xu,Feng Chen,Haiping Hu,Jianchang Gan
Al-water reaction for hydrogen production faces the problems of long induction time and low conversion efficiency at low temperature (below 273.15 K), which has seriously limited its applications. To realize the instant hydrogen production of Al composites at low temperature, low melting point metals (Ga, In, Sn) and additives (NaCl, g-C 3 N 4 , LiH) were selected to prepare Al composites with high reactivity. Compared with the other Al composites, Al alloy/NaCl/LiH/g-C 3 N 4 composites exhibit the enhanced low temperature hydrogen production performance in 23 wt% NaCl aqueous solution at 253.15 K. For all Al alloy/NaCl/LiH/g-C 3 N 4 composites, the induction time of Al-water reaction at 253.15 K has completely eliminated. The highest hydrogen generation volume of 1095 mL·gAl −1 and the maximum hydrogen generation rate of 120 mL·gAl −1 ·s −1 were obtained for Al alloy/NaCl/1.5%LiH/g-C 3 N 4 composite. It is proposed that LiH can induce Al-water reaction instantly starting at 253.15 K. The released heat and micro alkaline environment further promote the Al-water reaction and enhance the hydrogen conversion efficiency. In particular, g-C 3 N 4 additive can improve the antioxidant properties of Al composites. This study provides a novel way for the development and application of Al composites in real-time hydrogen production at low temperature.
研究领域:
材料科学
·
能源化学
✓ 已验证
产品关联
DOI
高影响因子
INORGANIC CHEMISTRY
·
2024
·
IF 4.3
Xiaoxiao Zheng,Xiaoping Chen,Xiaoqing Li,Jide Zhu,Jipeng Chen,Fengcai Lin,Lijuan Shen,Yanlian Xu,Lilong Jiang
The development of stable and effective catalysts to convert toxic H2S into high value-added sulfur is essential for production safety and environmental protection. However, the inherent defects of traditional iron- and zirconium-based catalysts, such as poor activity, high oxygen consumption, and low sulfur selectivity, limit their further developments and applications. Herein, the Fe–Zr bimetallic organic framework FeUIO-66(x) with different cubic morphologies was synthesized via a facile solvothermal method. The results indicate that the introduction of Fe not only increases the specific surface area and weak L-sites of the catalyst without changing its crystal structure, which provides enough reaction space and more active sites for the adsorption and activation of H2S, but also reduces the activation energy of the reaction, significantly promoting the selective oxidation of H2S. As a result, the as-obtained FeUIO-66(1) catalyst exhibits the highest desulfurization activity and superior durability and water resistance stability, and its H2S conversion and sulfur selectivity within 50 h are 100 and 88%, respectively. More importantly, the structure of the catalyst after the desulfurization reaction is consistent with that of the fresh counterpart. The study offers new insights into the development of effective and stable bimetallic catalysts to eliminate H2S and recycle sulfur.
研究领域:
催化化学
·
环境科学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
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
FUEL
·
2022
·
IF 8.035
Guang-Hui Liu,Jin-Jun Bai,Kun-Lang Lu,Hui Kan,Xiao-Qi Zhang,Yu-Hong Kang,Cui-Ying Lu,Zhan-Ku Li,Hong-Cun Bai,Xian-Yong Wei
Two flexible regulation systems were designed and used for the integrated catalytic hydroconversion (CHC) of lignocellulose to valuable oxygenated organic chemicals. Under the dual constraints of initial H 2 pressure (IHP) and temperature, three crop stalks can be almost completely degraded over a hydrothermally stable Ru/La(OH) 3 in one-pot, while the synergetic transfer of active hydrogen effectively promotes the cleavage of >C-O- bridged bonds in organic matter with highly complex structures during this period. As a result, abundant >C al -O- (>32%) and >C=O (>24%) derived platform chemicals such as alkanols, cyclanols, carboxylic acids, and esters were obtained at high IHP and low temperature. Correspondingly, various >C ar -O- (>50%) and >C=O (>30%) derived platform chemicals such as phenols, alkoxy-substituted phenols, ketones, and carboxylic acids dominated the derived bio-oils at low IHP and high temperature. The designed selective CHC strategies have the characteristics of convergent conversion to the two major derivative chemical demand directions. Therefore, these two atom-economic and effective degradation approaches are conducive to obtaining abundant functional small molecules, which can be further converted to various downstream platform products.
研究领域:
化学工程
·
生物质能
·
催化科学
✓ 已验证
DOI
高影响因子
FUEL
·
2024
·
IF 6.7
Guang-Hui Liu,Wen-Ao Shi,Jun Li,Han Wang,Ai-Min Wang,Yu-Hong Kang,Yong Gao,Ni Bai,Jie Kang,Chen Shi,Xian-Yong Wei
To produce high-density liquid fuels from lignite, a novel Ni-based bifunctional MCM-41/ β composite zeolite (Ni@ M / β ) is reported for the catalytic hydroconversion (CHC) of lignite-derived aryl ethers to high-yield polycyclic alkanes (PCAs). Ni@ M / β has a three-dimensional channel-type hierarchical porous texture with β as the core and MCM-41 as the shell. Stable Brønsted/Lewis acid sites and abundant internal/inter-zeolite defects also effectively promote the CHC of aryl ethers to PCAs. Under optimal conditions (5 MPa initial H 2 pressure and 160 °C), selectivities of 2-(benzyloxy)naphthalene (BON) and benzyloxybenzene derived PCAs are as high as 76.0 and 90.5 %, respectively, with dimers and trimers dominating. DFT calculation based on electrostatic potential distribution on the van der Waals surface and Mulliken charge distribution of BON and derived oxygenated monomers shows that aromatic intermediates with >C aromatic OH have multiple accessible sites and are easy to bind with cation/radical fragments. Therefore, it is speculated that PCAs are mainly derived from C-C coupling induced by cation/radical fragments after the activation of aromatic α -carbon. In addition, the activation of H 2 to H + , H · , δ+ H ··· H δ- , and H ··· H is mainly attributed to the strong Ni- M / β interaction and abundant defects. The whole CHC process is triggered mainly by the adsorption of H + released by Ni@ M / β at O sites of aryl ethers, and >C aliphatic -O- bridged bond cleavage is dominant. During this period, benzyl cation/radical produced by >C-O- bond cleavage and aromatic α -carbon activation (mainly) is coupled/reformed with adjacent aromatic fragments into corresponding polymers with non-oxygen bridged bonds, which are more easily converted to PCAs. This polycrystalline composite strategy improves the accessibility of large-sized molecules to active centers, and then increases the yields of PCAs, which is attractive for the clean and efficient conversion of lignite-derived oils to high-density liquid fuels.
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
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2020
·
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
·
催化
·
材料科学
·
生物化工
✓ 已验证
产品关联
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2019
·
IF 4.182
Fuxiang Feng,Xiaopo Niu,Li Wang,Xiangwen Zhang,Qingfa Wang
Ni/ZSM-5 nanosheet catalysts with different Si/Al ratios were modified by chemical liquid deposition (CLD) of tetraethoxysilane (TEOS) to tailor their acid spatial distribution. Their catalytic performance was evaluated with the hydroconversion of oleic acid to aviation-fuel-range-alkanes (AFRAs) at different reaction temperatures and H 2 pressures. The modified catalysts inherit the nanosheet structure with decreased external Brønsted acid concentration, especially the strong one. External Brønsted acid sites mainly favor the cracking of the deoxygenated products (C 17 /C 18 ). Internal Brønsted acid sites mainly enhance the isomerization of the linear AFRAs. And the catalytic activity of the external Brønsted acid sites was more sensitive to reaction temperature than that of the internal ones. The deoxygenation and cracking reactions were also more sensitive to H 2 pressure compared to the isomerization reaction. High AFRA selectivity of 51.4% as well as high iso/n -alkanes ratio of 1.7 were achieved at 250 °C and 10 bar over NS200(1).
研究领域:
催化化学
·
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）