INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2024
·
IF 3.8
Cong Wang,Gang Li,Zheng Huang,Anfeng Peng
The cumbersome air isolation process is one of the main constraints in the development of linear α-olefins prepared by ethylene oligomerization. An effective way to solve this problem is to eliminate the use of an alkyl-aluminum cocatalyst. Herein, two forms of Versailles/Santa Barbara-5 (VSB-5) (VSB-5-H3PO4 and VSB-5-NaH2PO2) are prepared and used as heterogeneous catalysts in ethylene oligomerization in the presence of LiAlH4 as a cocatalyst. Compared to other Ni-MOFs and Ni silica–aluminate catalysts, VSB-5s maintain a wider distribution of Linear α-olefin (LAO) products at relatively high activity. In the reuse test of the catalyst, the Al species from LiAlH4 cover the surface of the catalyst and decrease its activity, which could be removed by acid treatment. In situ IR studies show that active centers for ethylene oligomerization may form in VSB-5 assisted by LiAlH4. In addition, a Cossee–Arlman-type mechanism is proposed.
研究领域:
化学工程
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催化化学
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产品关联
DOI
高影响因子
Catalysts
·
2024
·Vol. 14
·期 1
·70
·
IF 3.8
Min Zhang,Hongwei Xiang,Xiaodong Wen
This investigation explores the synthesis of advanced catalysts for epoxidizing long-chain linear α-olefins, a pivotal process in the chemical industry for generating critical intermediates. Employing a hydrothermal technique, we developed four distinct catalysts (CS-1–4), methodically modulating the Ca/Sn ratio to elucidate its impact on the catalysts’ physicochemical properties. Our research uncovered that an escalated Ca/Sn ratio induces a morphological shift from octagonal to cubic structures, concomitant with a diminution in particle size and an enhancement in specific surface area. Significantly, the CS-3 catalyst outperformed others in 1-octene epoxidation, an efficacy attributed to its augmented surface alkalinity and proliferation of medium-strength alkaline sites, likely emanating from increased surface oxygen defects. Subsequent hydrogen reduction of CS-3 further amplified these oxygen defects, yielding a 10% uptick in catalytic activity. This correlation underscores the potential of oxygen defect manipulation in optimizing catalytic efficiency. Our findings contribute a novel perspective to the development of robust, high-performance catalysts for α-olefin epoxidation, seamlessly aligning with the principles of sustainable chemistry.Keywords:long-chain linear alpha-olefin;perovskite oxide;CaSnO3;oxygen vacancy;epoxidation
研究领域:
化学工程
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催化科学
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产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2020
·
IF 3.573
Meng Chen,Wei Lu,Hejun Zhu,Leifeng Gong,Ziang Zhao,Yunjie Ding
Linear α-olefins (C8–C12 α-olefin, LAOs) are acknowledged as high-value-added chemicals in both lubricant production and the polyolefin industry. An alternative route to the synthesis of high-purity LAOs is the dehydration of linear long-chain n-alcohols, whereas elevating the activity and selectivity of catalysts remains a challenge. Herein, we presented that on using sodium-modified γ-Al2O3 as the catalyst, a high selectivity (up to 96.87%) to 1-decene was achieved, and an optimized experimental condition (329 °C and 0.25 h–1) was found using the response surface method. Characterization results including X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET), pyrolysis (Py)-IR, NH3-temperature-programmed desorption (TPD), and CO2-TPD showed that a suitable ratio (∼0.4 wt %) of sodium impregnation could inhibit the strong acid sites of the catalyst, and sodium impregnation led to the formation of additional base sites, which accounted for the synergistic effect with other acid sites to promote further conversion of ethers to olefins. This work is of significance for the synthesis of LAOs from long-chain n-alcohols.
研究领域:
催化化学
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材料科学
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石油化工
✓ 已验证
产品关联
DOI
高影响因子
ENZYME AND MICROBIAL TECHNOLOGY
·
2025
·
IF 3.7
Yaqi Fu,Siyu Mao,Tianyue Liao,Wei Feng
The enzyme OleT can utilize H 2 O 2 as the co-substrate, and this biocatalysis is an H 2 O 2 -driven enzymatic catalysis. In this work, OleT was recombinated by being fused to an elastin-like polypeptide (ELP). The recombinant enzyme OleT-ELP exhibits higher stability and resistance to H 2 O 2 interference compared to native OleT. OleT-ELP showed improved catalytic efficiency in producing α-olefins via fatty acid decarboxylation. The recombinant 5-hydroxymethylfurfural oxidase ( HMFO-ELP) catalyzes the oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA), generating H 2 O 2 as a byproduct. Combining OleT-ELP with HMFO-ELP enabled simultaneous conversion of fatty acids and HMF. The in situ H 2 O 2 generated by HMFO-ELP was transferred to OleT-ELP, enhancing catalytic efficiencies for both α-olefins and FDCA production.
研究领域:
生物化学
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酶工程
·
绿色化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED CATALYSIS A-GENERAL
·
2024
·
IF 4.7
Cong Wang,Gang Li,Zheng Huang,Anfeng Peng
Alkyl-aluminum, which is sensitive to air, has been a major obstacle to the development of ethylene oligomerization. Herein, LiAlH 4 is used as an effective alkyl-aluminum substitute. The performance of LiAlH 4 itself in the reaction is investigated, proving that it possesses moderate activity. Further addition of Versailles/Santa Barbara-1 (VSB-1) catalysts with different morphologies can effectively improve the reaction, in which VSB-1/LiAlH 4 presents the activity of 32.1 g ‧ g LiAlH4 −1 ·h −1 (154.1 g ‧ g VSB-1 −1 ‧h −1 ) and the selectivity of 1-butene, 1-hexene and 1-octene in all products could reach 51.4 %, 18.9 % and 7.9 %, respectively. The co-catalytic system is stable and the VSB-1 catalyst therein can be effectively reused at least three times under the suitable treatment conditions. In addition, the product analysis of the co-catalyzed system reveals that the addition of VSB-1 catalyst tended to produce 1-butene, 1-hexene and 1-octene at 20 bar. Based on above result, a possible reaction mechanism is proposed.
研究领域:
化学工程
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催化科学
✓ 已验证
产品关联
DOI
高影响因子
Canadian Journal of Chemistry
·
2019
·Vol. 97
·期 4
·
IF 1.252
Jun Wang,Junyi Xie,Libo Wang,Yan Jiang,Na Zhang
A salen nickel complex has been prepared in good yield with ethylenediamine, salicylaldehyde, and NiCl2·6H2O as raw materials. The structure of the complex was characterized by FTIR, 1H NMR, UV, and ESI-MS. Upon activation with methylaluminoxane (MAO), the precatalyst showed high activity for ethylene oligomerization. To reduce the simultaneous production of insoluble polymers during the nickel-catalyzed ethylene oligomerization, a series of phenolic compounds were introduced as modifiers for the production of linear α-olefins. The researched result showed that the phenolic compounds have a significant impact on the selectivity of oligomers and the concentration of polymers. With the increase of phenolic compounds, the content of polymers decreased and the distribution of oligomers gradually shifted toward lighter olefins. The sterically hindered 4-tert-butyphenol proved to be an especially efficient polymer-retarding modifier among the studied phenolic compounds in this work. Furthermore, the retarding effect of phenolic compounds toward insoluble polymers may be mainly related to their interaction with MAO, giving rise to larger MAO aggregates.
研究领域:
化学工程
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催化科学
✓ 已验证
产品关联
DOI
高影响因子
ChemSusChem
·
2020
·Vol. 13
·期 18
·4922-4928
·
IF 7.962
Zihao Zhang,Wenwen Lin,Yafei Li,Francis Okejiri,Yubing Lu,Jixing Liu,Hao Chen,Xiuyang Lu,Jie Fu
Graphical Bimetallic boost : A NiFe/C bimetallic catalyst is reported, composed of NiFe alloy in the material bulk and a surface mixture of NiFe alloy and oxidized NiFe δ + species, exhibiting a heptadecene yield of 70.1 % with selectivity to 1-heptadecene as high as 92.8 % at just 190 °C. Catalytic deoxygenation of even-numbered fatty acids into odd-chain linear α-olefins (LAOs) has emerged as a complementary strategy to oligomerization of ethylene, which only affords even-chain LAOs. Although enzymes and homogeneous catalysts have shown promising potential for this application, industrial production of LAOs through these catalytic systems is still very difficult to accomplish to date. A recent breakthrough involves the use of an expensive noble-metal catalyst, Pd/C, through a phosphine ligands-assisted method for LAOs production from fatty acid conversion. This study presents a unique, cost-friendly, non-noble bimetallic NiFe/C catalyst for highly selective LAOs production from fatty acids through decarbonylative dehydration. In the presence of acetic anhydride and phosphine ligand, a remarkable improvement in the yield of 1-heptadecene from the conversion of stearic acid was found over the supported bimetallic catalyst (NiFe/C) as compared to corresponding monometallic counterparts (Ni/C and Fe/C). Through optimization of the reaction conditions, a 70.1 % heptadecene yield with selectivity to 1-heptadecene as high as 92.8 % could be achieved over the bimetallic catalyst at just 190 °C. This unique bimetallic NiFe/C catalyst is composed of NiFe alloy in the material bulk phase and a surface mixture of NiFe alloy and oxidized NiFe δ+ species, which offer a synergized contribution towards decarbonylative dehydration of stearic acid for 1-heptadecene production.
研究领域:
化学工程
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催化科学
✓ 已验证
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2021
·
IF 19.503
Weifeng Tu,Chao Sun,Zhengzhou Zhang,Wenqi Liu,Haripal Singh Malhi,Wei Ma,Minghui Zhu,Yi-Fan Han
This work unravels the chemical and structural properties of Fe 5 C 2 -ZnO catalysts decorated with sodium (Na) during CO 2 hydrogenation to linear α-olefins, determined by rate assessments and series of in-situ characterizations. Reaction network remains as a combination of reverse water-gas-shift (RWGS) and CO hydrogenation, but their relative contributions vary. The RWGS reaction is chemically equilibrated, thus CO 2 conversion is determined solely by the thermodynamic constraint. However, Na addition alleviates the formation rates of paraffins from the subsequent CO hydrogenation and reactions of olefins with hydrogen. Na additive does not alter the structures of Fe 5 C 2 -ZnO, but improves largely the stability of Fe 5 C 2 by preventing the phase oxidation during the reaction. Na modifies the surface properties of catalyst, thus facilitates reaction of CO* and H* and the C C bond formation. The dual role of Na leads more effective olefins turnovers and provides new insights to the design of novel catalysts for CO 2 utilization.
研究领域:
催化化学
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材料科学
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产品关联
DOI
高影响因子
TRANSITION METAL CHEMISTRY
·
2019
·Vol. 44
·期 7
·681-688
·
IF 1.016
Wang Jun,Liu Jinyi,Chen Liduo,Lan Tianyu,Wang Libo
A series of bispyridylamine ligands and chromium complexes designed for ethylene oligomerization have been synthesized, which was made up of both neutral organic ligand and inorganic anion. The compositions of these complexes have been fully characterized by spectroscopic and analytical methods. Catalysts ( Cr1 – Cr4) were evaluated in detail with methylaluminoxane (MAO) as an activator in the ethylene oligomerization. As a result, Cr1 achieved a higher catalytic activity of 2.93 × 10 5 g/(mol(Cr) h) and a higher selectivity of 55.34% toward the valuable C 8 compound using toluene as the solvent. The total selectivity to LAOs was 71.2%.
研究领域:
催化化学
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有机合成
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2021
·
IF 7.312
Tongtong Ren,Suli Liu,Hong Li,Angui Zhang,Xingang Li,Wei Yuan,Xin Gao
Utilization of F-T synthetic to produce value-added C 8 linear α-olefin is a promising alternative approach, however, the purification of α-olefin from F-T synthetic products is a great challenge, especially for removing 2-methyl-1-heptene (MH). This article addresses the novel method of etherification reaction to remove MH from F-T synthetic products, and develop by far the most efficiency reactive distillation (RD) method to intensified the etherification process. The scarcity of thermodynamic data was measured and regressed by the activity coefficient models, furthermore, kinetics of the etherification reaction of MH with methanol was explored using an ion exchange resin as catalyst, and then fitted by a pseudo-homogeneous model. The pilot-scale RD experimental results show that the conversion of MH reaches 91.83 % and the purity of α-olefin increases by 14.9 wt% (percentage points). Process analysis method was used to realize the optimization of design and operating parameters of etherification RD column based on the developed rigorous model. The optimization results show that the conversion of MH achieves 99.74 % and the purity of α-olefin achieves 96.87 wt%, which is also illustrated that the novel method for removing MH is proposed paving the way for purification of α-olefin from F-T synthetic products.
研究领域:
化学工程
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石油化学
✓ 已验证
DOI
高影响因子
Nature Catalysis
·
2024
·Vol. 7
·期 6
·666-677
·
IF 42.8
Dou Xiaomeng,Yan Tao,Qian Lixiang,Hou Huaming,Lopez-Haro Miguel,Marini Carlo,Agostini Giovanni,Meira Debora M.,Zhang Xiangjie,Zhang Liang,Cao Zhi,Liu Lichen
Achieving the regioselective hydroformylation of linear α-olefins to linear aldehydes using solid catalysts with regioselectivities comparable to the corresponding homogeneous process is a great challenge in the chemical industry. Despite the tremendous efforts devoted to this research topic, most of the reported heterogeneous metal catalysts still give considerably lower regioselectivities than well-established homogeneous metal catalysts. Here we show the design of efficient Rh-zeolite catalysts, in which subnanometre Rh clusters are selectively confined in the sinusoidal ten-membered-ring channels of MFI zeolite, for the hydroformylation of long-chain linear α-olefins (C 6 –C 12 ) into linear aldehydes with very high linear-to-branched aldehyde ratios (up to 400). The exceptional catalytic performances result from the involvement of the MFI zeolite framework as a rigid solid ligand that accommodates subnanometre Rh clusters in the sinusoidal channels of the MFI zeolite.
研究领域:
化学工程
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催化
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2022
·
IF 8.035
Songpeng Cheng,Liangcheng An,Zhenling Li,Suli Liu,Junmin Lv,Subing Fan,Tiansheng Zhao
The products with higher carbon numbers from Fischer-Tropsch (F-T) synthesis are very complex and hard to directly be analyzed on GC due to their very high boiling point. In this work, the qualitative and quantitative analytical method for refined F-T wax samples with C 7 to C 38 was established on GC–MS. All components were well separated, qualified and quantified. The analytical errors were less than ±2 % and the errors of recovery experiments were less than ±5 %. Thereafter, this method was successfully applied in GC analysis with errors less than ±0.75 % and the analytical method on GC was also built, which will provide a more convenience way in analysis of refined F-T wax samples. Based on the obtained analytical conditions and the relative calibration factors of paraffins, the qualitative and quantitative method for the cracking products from refined F-T wax was further built according to a similar method by using simulated samples with the conversion from 5 % to 80 %. The thermal cracking of F-T wax 5# was performed and the content of LAOs in liquid mixtures reached over 50 % at 650 °C. This study simplifies the previous analysis methods which can only be completed by using a variety of standard methods and provide convenience for analysis of refined F-T wax from coal-to-liquid plant.
研究领域:
化学工程
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分析化学
·
石油化学
✓ 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）