Reaction Chemistry & Engineering
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2025
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IF 3.1
Xueqian Zhang,Jiasong Yan,Shuai Yuan,Shanqing Yu,Qingyu Liu,Xikai Wang,Rui Li
Whether cycloalkanes undergo six- or five-membered ring-opening reaction pathways remains controversial. In this work, the catalytic cracking reactions of cyclohexene and 1-methylcyclopentene, as model compounds, were investigated in a pulse microreactor. The characteristics of the reactions of the two model compounds were compared in terms of isomerization, cracking, and hydrogen transfer reaction, and the reasons for the differences in their catalytic reactions were analyzed in combination with thermodynamic and molecular simulation calculations. The results have shown that the catalytic cracking product distributions of cyclohexene and 1-methylcyclopentene were similar owing to their easy mutual isomerization; the five-membered ring-opening cracking pathway was more thermodynamically advantageous than that of six-membered ring-opening cracking, and therefore, the yield of the ring-opening cracking product of 1-methylcyclopentene was comparatively higher; the main products of the hydrogen transfer reaction of the two compounds were alkanes and aromatic hydrocarbons. By comparing the product distributions and reaction activation energies, the ring-opening reaction pathways were clarified, and the catalytic cracking reaction networks of cyclohexene and 1-methylcyclopentene were established.
研究领域:
化学
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催化反应
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DOI
高影响因子
Catalysis Science & Technology
·
2022
·Vol. 12
·期 19
·5879-5890
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IF 6.177
Dengfeng Dai,Chao Feng,Minmin Wang,Qingzhou Du,Dandan Liu,Yuan Pan,Yunqi Liu
Biomass-based chemicals as a renewable alternative to petroleum-based chemicals are of great significance. The conversion of biomass-based furfuryl alcohol to pentanediol, including 1,5-pentanediol and 1,2-pentanediol, is explored over a series of bifunctional Cu/MFI catalysts in a continuous-flow reactor. These catalysts are synthesized by supporting copper nanoparticles on MFI zeolites with varying molar ratios of SiO2/Al2O3. Among them, the Z60-10Cu catalyst containing balanced Cu0–Cu+ and Brønsted acid sites exhibits excellent performance, and a high furfuryl alcohol conversion of 99.5% and selectivity of 85.2% for 1,5-pentanediol (69.2%) and 1,2-pentanediol (16.0%) could be achieved (hydrogen pressure: 2.5 MPa) at 160 °C. The experimental results and the results obtained using the DFT technique revealed that the high catalytic activity realized during the processes of ring-opening and hydrogenation could be attributed to the synergistic effect between the Cu species and Brønsted acid sites. The Brønsted acid sites on the Si(OH)Al groups significantly affect the ring-opening process of furfuryl alcohol. The methoxy group on furfuryl alcohol adsorbs on the Cu+ sites, and the hydrogenation saturation of the ring-opening intermediate is realized under the influence of the activated hydrogen units on the Cu0 sites. The results reported herein could help promote the continuous production of high value-added pentanediol from biomass-based raw materials in the presence of non-noble metal catalysts. An economical and feasible path for the transformation of biomass resources into high value-added fine chemicals could also be developed.
研究领域:
生物化学
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催化化学
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材料科学
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DOI
高影响因子
ChemSusChem
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2024
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IF 7.5
Shenyu Wang,Junjie Zhang,Ying Zhang
Graphical The CoO@Co core-shell catalyst, 7Co-0.2Fe/CeO 2 , efficiently catalyzes the hydrogenation and ring-opening of furfural to 1,5-pentanediol, with a high productivity of 54.76 mmol/g Co /h, representing the top activity level among the reported catalysts. The addition of Fe optimizes the Co 2+ /Co 0 ratio, improves substrate adsorption, and prevents the formation of tetrahydrofurfuryl alcohol, a saturated furan byproduct. In the conversion of furfural using non-noble metal catalysts, preferential cleavage of the C2−O bond followed by hydrogenation of the C=C bond facilitates selective access to valuable 1,5-pentanediol (1,5-PeD). Herein, we developed CeO₂ loaded core-shell CoO@Co nanoparticle catalysts. Adjusting Co loading, Fe doping, and reduction temperature improved reaction efficiency. 7Co-0.2Fe/CeO₂ catalysts reduced at 500 °C demonstrated optimal performance. 1,5-PeD produced at 54.76 mmol/g Co /h, representing the top activity levels among the reported catalysts. H₂-TPR, XRD, HAADF-STEM, FT-IR, XPS, and XANES were employed to investigate the catalyst structure-activity relationship. Co 2+ cleaves furan ring C−O bond, Co⁰ promotes double-bond hydrogenation. The CoO@Co structure favors the desired 1,5-PeD production route. Trace Fe species optimize the Co 2+ /Co⁰ ratio, enhance the substrate adsorption, and inhibit the furan ring saturation. These findings emphasize the importance of fine-tuning catalyst structure and composition for selectivity improvement.
研究领域:
化学工程
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催化科学
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可再生资源转化
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DOI
PubMed
高影响因子
CATALYSIS LETTERS
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2022
·Vol. 153
·期 7
·2107-2114
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IF 2.936
Zhao Wenli,Niu Xiaopo,Liu Guangni,Zhang Xiurong,Wang Qingfa
Three kinds of Pt nanocrystals with different morphologies (5 nm cubes, 10 nm cubes and 5 nm truncated octahedrons) were synthesized and employed to fabricate Pt/CNT-USY catalysts for selective ring opening of decalin. The 5 nm truncated octahedral Pt/CNT-USY with exposed (100) and (111) facets exhibited higher yield of ring-opening products (53.9 wt%) than the CNT-USY-supported 5 nm cubic Pt catalyst enclosed by the (100) facets (39.6 wt%). Moreover, the 5 nm cubic Pt showed better catalytic activities compared to the 10 nm cubic Pt/CNT-UST catalyst, which ascribed to the smaller size of Pt NCs enriched more revealable metal active sites. DFT calculations demonstrated that the adsorption of decalin on Pt (111) was stronger than that on Pt (100) facets, which was profitable for the selective ring-opening reaction. Graphical Abstract
研究领域:
催化化学
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材料科学
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理论计算化学
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DOI
高影响因子
WATER RESEARCH
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2017
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IF 6.942
Xing Ding,Shengyao Wang,Wanqiu Shen,Yi Mu,Li Wang,Hao Chen,Lizhi Zhang
In this study, an electrochemical/electro-Fenton oxidation (EC/EF) system was designed to degrade atrazine, by utilizing boron-doped diamond (BDD) and Fe@Fe 2 O 3 core-shell nanowires loaded active carbon fiber (Fe@Fe 2 O 3 /ACF) as the anode and the cathode, respectively. This EC/EF system exhibited much higher degradation rate, decholorination and mineralization efficiency of atrazine than the electrochemical (EC) and electrochemical/traditional electro-Fenton (EC/TEF) oxidation counterpart systems without Fe@Fe 2 O 3 core-shell nanowires. Active species trapping experiment revealed that Fe@Fe 2 O 3 could activate molecular oxygen to produce more OH through Fenton reaction, which favored the atrazine degradation. High performance liquid chromatography , high performance liquid chromatography-mass spectrometry and gas chromatography-mass spectrometry were applied to probe the decomposition and mineralization of atrazine during this novel EC/EF process, which revealed that two intermediates of triazinons (the isomerization of hydroxylated atrazine) were generated during the electrochemical/electro-Fenton oxidation of atrazine in the presence of Fe@Fe 2 O 3 core-shell nanowires. The experimental and theoretical calculation results suggested that atrazine might be degraded via a triazinon ring opening mechanism, while the presence of Fe@Fe 2 O 3 notably accelerated the decholorination process, and produced more hydroxylated products to promote the generation of trazinons and the subsequent ring cleavage as well as the final complete mineralization. This work provides a deep insight into the triazine ring opening mechanism and the design of efficient electrochemical advanced oxidation technologies (EAOTs) for persistent organic pollutant removal .
研究领域:
环境科学
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化学工程
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DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2023
·
IF 11.4
Xifen Zhu,Yuanyuan Yu,Weikun Meng,Jiahui Huang,Guanyong Su,Yin Zhong,Xiaolong Yu,Jianteng Sun,Ling Jin,Ping’an Peng,Lizhong Zhu
Fluorinated liquid crystal monomers (FLCMs) have been suggested as emerging contaminants, raising global concern due to their frequent occurrence, potential toxic effects, and endurance capacity in the environment. However, the environmental fate of the FLCMs remains unknown. To fill this knowledge gap, we investigated the aerobic microbial transformation mechanisms of an important FLCM, 4-[difluoro(3,4,5-trifluorophenoxy)methyl]-3, 5-difluoro-4′-propylbiphenyl (DTMDPB), using an enrichment culture termed as BG1. Our findings revealed that 67.5 ± 2.1% of the initially added DTMDPB was transformed in 10 days under optimal conditions. A total of 14 microbial transformation products obtained due to a series of reactions (e.g., reductive defluorination, ether bond cleavage, demethylation, oxidative hydroxylation and aromatic ring opening, sulfonation, glucuronidation, O-methylation, and thiolation) were identified. Consortium BG1 harbored essential genes that could transform DTMDPB, such as dehalogenation-related genes [e.g., glutathione S-transferase gene (GST), 2-haloacid dehalogenase gene (2-HAD), nrdB, nuoC, and nuoD]; hydroxylating-related genes hcaC, ubiH, and COQ7; aromatic ring opening-related genes ligB and catE; and methyltransferase genes ubiE and ubiG. Two DTMDPB-degrading strains were isolated, which are affiliated with the genus Sphingopyxis and Agromyces. This study provides a novel insight into the microbial transformation of FLCMs. The findings of this study have important implications for the development of bioremediation strategies aimed at addressing sites contaminated with FLCMs.
研究领域:
环境科学
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微生物学
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DOI
PubMed
高影响因子
Environmental Technology & Innovation
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2021
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IF 5.263
Yuying Zhu,Baoqiang Chang,Xue Sun,Haijian Luo,Wenhui Wang,Chaolin Li
The presence of venlafaxine, one of the popular antidepressants, in environmental aquatic media has become a rising issue and potential threat to global ecology and human health. However, advanced technologies for efficient venlafaxine degradation remain underdeveloped. Herein, we propose to use chloride-mediated electrochemical degradation to efficiently remove venlafaxine in aqueous media. The degradation rate of venlafaxine can be significantly increased when Cl − is added to the conventional electrochemical degradation process. It is found the Cl − can convert to Cl ⋅ , which selectively attacks benzene ring and accelerates its opening, thus leading to the improved degradation and mineralization performance of venlafaxine. Based on the analysis of reactive species and degradation intermediates, the degradation pathways with and without Cl − were proposed. Toxicity test demonstrates that the toxic oxidation products formed during venlafaxine degradation could be completely mineralized in the chloride-mediated electrochemical degradation process. This work demonstrates the chloride-mediated advanced oxidation technology may be a promising way to degrade venlafaxine, which may also apply to other emerging antidepressants contained benzene ring, thus paving a new route for the removal of organic pollutants.
研究领域:
环境科学
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药理学
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化学工程
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DOI
高影响因子
Journal of the American Chemical Society
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2014
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IF 11.444
Xibin Pang,Wei Chang,Chuncheng Chen,Hongwei Ji,Wanhong Ma,Jincai Zhao
The molecules O2 and H2O dominate the cleavage of aromatic sp2 C–C bonds, a crucial step in the degradation of aromatic pollutants in aqueous TiO2 photocatalysis, but their precise roles in this process have remained elusive. This can be attributed to the complex oxidative species involved and to a lack of available models for reactions with a high yield of direct products. Here, we used oxygen-18 isotope labeled O2 and H2O to observe the aromatic ring-opening reaction of the model compound 3,5-di-tert-butylcatechol (DTBC), which was mediated by TiO2 photocatalysis in an aqueous acetonitrile solution. By analyzing the primary intermediate products (∼75% yield), especially the seven-membered ring anhydrides that were formed, we obtained direct evidence for the oxygen atom of dioxygen insertion into a C–C bond of the aromatic ring. This indicates that molecular oxygen is the ultimate ring-opening agent in TiO2 photocatalysis and that it undergoes single O atom incorporation rather than the previously proposed molecular oxygen 1,2-addition processes. The ratio of intradiol to extradiol products depends on the particle size of TiO2 catalysts used, which suggests that the O2 activation is correlated with the available coordination sites on the TiO2 surface in the photocatalytic cleavage of the aromatic ring.
研究领域:
环境科学
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化学
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DOI
高影响因子
MATERIALS RESEARCH BULLETIN
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2023
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IF 5.4
Dongxiu Lu,Ruhui Ma,Yuan Chen,Yuancai Chen
In this study, Ni-doped Ti/SnO 2 -Sb anode (Ti/NATO) was prepared and used for electrocatalytic ozone production and in-situ activated peroxymonosulfate (E-Ti/NATO-PMS) to degrade bisphenol A (BPA). SEM, XRD and XPS results indicated that Ni doping could influence the transformations of Sb 5+ and Sb 3+ ions, which decreased the agglomeration of crystallites and increased the O ads and oxygen vacancy (O v ) concentrations. Ti/NATO 1.0 anodes significantly improved the ozone production via outcompeting of the adsorbed O 2ads over water, and inhibiting the desorption of O 2ads , to obtain the highest O 3 concentration with low onset potential and high oxygen evolution potential. E-Ti/NATO 1.0 -PMS system obtained over 92% BPA degradation within 60 min at 10 mA cm −2 and pH ranging from 4 to 10. Radical scavenging experiments revealed that O 3 in situ generated could directly electro-activate PMS into •O 2 − and 1 O 2 . The E-Ti/NATO 1.0 -PMS process could detoxify the BPA through chain scission, rearrangement and ring opening processes, and exhibited great potentials for application.
研究领域:
环境科学
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化学工程
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水处理
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DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
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2024
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IF 2.7
Xiong-Li Liu,Shuang Chen,Xi-Rui Wang,Wei-Na Wang,Ke-Lan Xu,Pan Hu,Ying Zhou,Bo-Wen Pan,Qi-Lin Wang
Here, we demonstrate that the first example of harmaline scaffolds serving as acceptor/acceptor-based N-C-C synthons-triggered the ring opening and skeletal reconstruction of 3-vinyl benzofuranones for the construction of a library of skeletally-diverse polycyclic harmaline scaffolds. These products were smoothly afforded in up to 77% yield, >20:1 dr under catalyst-free conditions, and expanded the chemical space of biologically significant harmaline derivative species. All synthetic compounds showed cytotoxic activity against tumor cells, especially the compound 3at, which exhibited selective cytotoxicity against A549 cells and lower cytotoxicity against normal cells MRC-5 and HK-2. In further mechanism research, 3at inhibited A549 cell proliferation through the G1 phase arrest, induced A549 cell apoptosis through internal and external apoptosis pathways, and suppressed the migration and invasion abilities of A549 cells. These data indicated that compound 3at is the most effective compound in the series and can serve as a promising precursor for drug development.
研究领域:
药物化学
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肿瘤学
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药学
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DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2023
·
IF 13.6
Guangrong Sun,Han Yeong Kaw,Meijiao Zhou,Pei Guo,Lizhong Zhu,Wei Wang
Identification of emerging disinfection byproducts (DBPs) of health relevance is important to uncover the health risk of drinking water observed in epidemiology studies. In this study, mutagenic chlorinated nucleotides were proposed as potential DBPs in drinking water, and the formation and transformation pathways of these DBPs in chlorination of nucleotides were carefully investigated. A total of eleven chlorinated nucleotides and analogs were provisionally identified as potential DBPs, such as monochloro uridine/cytidine/adenosine acid and dichloro cytidine acid, and the formation mechanisms involved chlorination, decarbonization, hydrolysis, oxidation and decarboxylation . The active sites of nucleotides that reacted with chlorine were on the aromatic heterocyclic rings of nucleobases, and the carbon among the two nitrogen atoms in the nucleobases tended to be transformed into carboxyl group or be eliminated, further forming ring-opening or reorganization products. Approximately 0.2–4.0 % (mol/mol) of these chlorinated nucleotides and analogs finally decomposed to small-molecule aliphatic DBPs, primarily including haloacetic acids, trichloromethane, and trichloroacetaldehyde. Eight intermediates, particularly chlorinated imino- D -ribose and imino- D -ribose, were tentatively identified in chlorination of uridine. This study provides the first set of preliminary evidence for indicating the promising occurrence of chlorinated nucleotides and analogs as potential toxicological-relevant DBPs after disinfection of drinking water.
研究领域:
环境科学
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水处理
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毒理学
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化学
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DOI
PubMed
高影响因子
RESEARCH ON CHEMICAL INTERMEDIATES
·
2023
·Vol. 49
·期 10
·4257-4274
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IF 3.3
Cao Wenbo,Ren Haitao,Cai Chaochen,Li Dashuai,Li Tingting,Lou Chingwen,Lin Jiahorng
Photocatalysis is a promising technology for wastewater treatment. It is a key problem to develop photocatalytic materials that can efficiently remove tetracycline (TC) under weak light intensity. This article synthesized the UiO-66-NH 2 /Bi 2.15 WO 6 heterojunction using a solvothermal method, and its specific surface area increases by 2.1 times relative to Bi 2.15 WO 6 , endowing good adsorption capacity for TC. Compared with Bi 2.15 WO 6 , the heterojunction effectively improves the separation of electrons and holes and enhances the photocatalytic performance. Under weak light intensity (4 mW cm −2 ), the removal percentage of 50 mg L −1 TC can reach 78.0%, attributing to a synergistic effect between adsorption and photocatalysis. The free radical capture experiment showed that TC was photodegradation mainly under the action of hole (h + ) and superoxide radical (·O 2 − ). Finally, through LC/MS analysis, it is inferred that TC is degraded into H 2 O and CO 2 after a series of reactions such as deamination, dehydroxylation, amide bond breaking and ring opening. This study provides insights for the synthesis of more powerful photocatalysts for TC removal.
研究领域:
环境科学
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材料科学
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化学工程
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水处理
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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）