CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Liqin Zhou,Kungang Chai,Xingdong Yao,Hongbing Ji
It is highly desirable to design and fabricate porous bio-based adsorbent for efficient and selective recovery of acetophenone (AP) and 1-phenylethanol (PE) from the effluent of propylene oxide and styrene monomer co-production (PO/SM) process. Herein, using cassava starch as the starting material, starch-graft-styrene hypercrosslinked polymers (SSHCPs) were designed and synthesized facilely by starch-graft-styrene copolymerization and subsequent crosslinking via a Friedel-Crafts alkylation route. SSHCP-3 (knitted by 4,4′-bis-(chloromethyl)-1,1′-biphenyl) shows high BET surface area (818 m 2 ·g −1 ), large pore volume, and high thermal stability, making it a highly efficient adsorbent for removal of aromatic pollutants from water. SSHCP-3 showed high uptake for AP (2.82 mmol·g −1 ) and selectivity (4.95) of AP over PE in binary-solute adsorption experiments. Spectral studies and theoretical calculation demonstrated that AP and PE uptake could occur at glucose units and benzene moiety via van der Waals interaction and π-π stacking interactions. SSHCP-3 also showed excellent adsorption efficiency of AP (93.6%) and PE (74.4%) in the wastewater discharged from PO/SM process. These results demonstrated that transforming styrene and starch to bio-based hypercrosslinked polymers provides an environmentally friendly and attractive strategy for recovery of AP and PE in practical application.
研究领域:
环境科学
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材料科学
·
化学工程
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DOI
高影响因子
POLYCYCLIC AROMATIC COMPOUNDS
·
2016
·
IF 0.959
Hongyun Nie,Maiqian Nie,Yongzhe Yang,Jing Zhao,Xinyi Zhang,Yutao Guo,Yi Wan,Jing Zi
Characterization of phenol metabolization by P. stutzeri N2 was proposed based on the identification of relevant metabolites and enzyme activities of catechol 1,2-oxygenase and catechol 2,3-dioxygenase. P. stutzeri N2 started to grow on 400 mg l−1 phenol with no obvious lag phase, and then phenol decomposition was rapidly completed within 32 h. Results of enzyme activities, UV spectrums of cultures, and the mass spectrum identification of cis, cis-muconic and 2-HMS, which showed that catechol C12O and C23O were acting simultaneously on the fission of the phenol ring. The existence of P-hydroxybenzoic acid and straight-chain saturated dicarboxylic acids in the culture medium showed that carboxylation and hydrogenation were involved during the phenol degradation. Metabolites containing five or four carbons indicated that catechol and its immediate ring-cleavage intermediates could be furthermore metabolized by P. Stutzeri N2. Therefore, P. stutzeri N2 which could degrade phenol with high efficiency and diverse pathways could have potential applications in the treatment of wastewater containing phenol.
研究领域:
环境微生物学
·
生物化学
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产品关联
DOI
高影响因子
CATALYSIS COMMUNICATIONS
·
2018
·
IF 3.463
Baojiao Gao,Coco Bi
N-hydroxyphthalimide (NHPI) was synchronously synthesized and immobilized on crosslinked polystyrene (CPS) microspheres via a short-cut of polymer reactions, obtaining the heterogenous catalyst. Some compositional catalysts were constituted by CPS-NHPI microspheres and metal salts, and they were used in the oxidation reactions of 1-phenylethanol with molecular oxygen as oxidant. Among four co-catalysts, vanadyl acetacetonate (VO(acac) 2 ), Co(OAc) 2 , CoCl 2 and Mn(OAc) 2 , the catalytic activity of VO(acac) 2 is the best although cobalt and manganese salts are conventional co-catalysts of NHPI. Under mild conditions, CPS-NHPI microspheres in combination with VO(acac) 2 can transform selectively 1-phenylethanol into acethenone with a conversion of 40%.
研究领域:
化学
·
催化反应
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产品关联
DOI
高影响因子
MATERIALS CHEMISTRY AND PHYSICS
·
2023
·
IF 4.6
Yang Xue,Xiangxin Meng,Bixiu Yuan,Huifang Xu
Fabrication of polymer porous xerogel with environment-friendly and simplified procedure is important target for reducing pollution and production cost. In this research, a sustainable method to prepare thermal insulator of polysiloxane-phenolic composite porous xerogel monoliths was studied by replacing hazardous and volatile formaldehyde with terephthalaldehyde in phenolic component and applying facile ambient drying process. The homogeneous dispersion of poly(methylphenylsiloxane) and resorcinol-terephthalaldehyde in xerogels was achieved by adjusting catalysis condition, water-ethanol content and prepolymer component. Typical poly(methylphenylsiloxane) and resorcinol-terephthalaldehyde composite xerogel monolith had density of about 0.3 g/cm 3 , 65.4% mass retention rate at 800 °C under nitrogen atmosphere, and thermal conductivity 0.063 W/(m·K) at room temperature. According to Thermogravity analysis coupled with Fourier Transform Infrared Spectra (TG-FTIR), pyrolysis mechanism and structure transformation were revealed. The typical pyrolyzed derivatives at 600 °C and 800 °C well preserved the integrated structure, low density, thermal insulation property, and thermal oxidation stability.
研究领域:
材料科学
·
环境科学
·
化学工程
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产品关联
DOI
高影响因子
Catalysis Science & Technology
·
2024
·
IF 4.4
Renjie Deng,Huajie Liu,Haishuai Cui,Yao Tian,Hai Yang
In this work, we have developed a green method for the preparation of para-nitrotoluene through the catalytic nitration of toluene with nitrogen dioxide (NO2) under the promotion of dioxygen (O2). The experimental results reveal that the dealumination of Hβ zeolite has a significant effect on the catalysis of the developed NO2–O2–acetic anhydride (Ac2O) system, in which the conversion of toluene is 78.1% and the selectivity to para-nitrotoluene is 71.8%. Furthermore, the nature of different dealuminated catalysts was investigated by nitrogen adsorption–desorption analysis, X-ray diffraction (XRD), Fourier-transform infrared (FT-IR), thermal gravimetric analysis (TGA), inductively coupled plasma (ICP), ammonia temperature-programmed desorption (NH3-TPD), pyridine adsorbed Fourier-transform infrared (Py-FT-IR), scanning electron microscopy (SEM) and 27Al magic-angle spinning nuclear magnetic resonance (27Al MAS NMR) techniques. The results of characterization indicate that the structure of the Hβ zeolite still remains and that of Al species in the extra-framework is preferentially removed after acid treatment. Based on the combined results of catalytic characterization and DFT calculation, a feasible reaction mechanism of improved para-selectivity in toluene nitration was suggested for the NO2–O2–Ac2O system.
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
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2024
·
IF 3.8
Da Sheng,Qing He,Zhong-Hua Cao,Lun-Bo Chen,Song-Hai Wu,Yong Liu,Hai-Tao Ren,Xu Han
Although photooxidation of benzyl alcohol to benzaldehyde in aqueous solution is an important chemical process, its selectivity cannot be readily controlled due to the overoxidation of benzaldehyde. In this study, a series of Bi–Mo/CN photocatalysts are synthesized, and their reactivity in photooxidation of benzyl alcohol under visible light is compared. Bi–Mo/CN-2 exhibits high photocatalytic reactivity in the conversion of benzyl alcohol (51%) with a high selectivity toward benzaldehyde of 99.9%. In this process, the formed ≡Bi–OO• and ≡Bi–OOH selectively oxidize benzyl alcohol to benzaldehyde via the H-abstraction pathway after O2 is photoreduced on Bi–Mo/CN, accompanied by the formation of H2O2. Meanwhile, the doped Mo utilizes the produced H2O2 or ≡Bi–OOH to produce ≡Mo–O2 peroxo, which not only contributes to the selective oxidation of benzyl alcohol to benzaldehyde but also effectively prevents overoxidation of benzaldehyde. This work provides new insight into designing novel photocatalysts for selective oxidation of organic substrates.
研究领域:
化学
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材料科学
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产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL RESEARCH
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2020
·
IF 0.593
Zhenzhen Geng,Hong-yu Zhang,Guohui Yin,Yuecheng Zhang,Jiquan Zhao
The ionic liquid 1-methyl-3-(3-sulfopropyl)imidazolium chloride ([MIMPs]+Cl-) in combination with 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) and sodium nitrite (NaNO2) as a catalytic system demonstrates high efficiency in the one-pot two-step aerobic oxidative condensation of benzyl alcohols with 1,2-phenylenediamines to give benzimidazoles. Various benzimidazoles are obtained in good to excellent yields by this strategy.
研究领域:
有机化学
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催化化学
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DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2022
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IF 9.221
Yuhuan Zhang,Hongjuan Li,Shiguo Sun,Yongqian Xu
Triphenylphosphine (PPh 3 ) and tetrakis(triphenylphosphine)palladium (Pd(PPh 3 ) 4 ) are harmful at extremely low concentration, thus it is essential to explore selective and sensitive method to detect them. Based on Staudinger reaction mechanism, here we present a simple excited-state intramolecular proton transfer (ESIPT) fluorescent probe (HBTN) for detection of PPh 3 and Pd(PPh 3 ) 4 over other phosphine derivatives with differential channel fluorescence (enol and keto emission). The reaction-typed fluorescence probe with novel Staudinger reaction mechanism offers very low autofluorescence and a large signal-to-noise response signal, which is beneficial for the sensitive detection of PPh 3 and Pd(PPh 3 ) 4 . Moreover, HBTN can be used for efficiently detecting Pd(PPh 3 ) 4 residues in highly purified products and imaging PPh 3 in living cells.
研究领域:
分析化学
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生物医学
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DOI
高影响因子
Catalysis Science & Technology
·
2021
·Vol. 12
·期 2
·652-663
·
IF 6.119
Chuanyu Yang,Zhongwen Dong,Weifeng Chu,Yanan Wang,Dongpu Zhao,Fucun Chen,Wenjie Xin,Xiangxue Zhu,Shenglin Liu,Longya Xu
A series of beta zeolite catalysts with controllable particle sizes and similar Si/Al ratios were prepared by introducing imidazole (IMD) into the synthesis system and used for liquid-phase transalkylation of diethylbenzene (DEB) with benzene (Bz). The beta zeolite catalyst prepared with an IMD/SiO2 molar ratio of 0.5 possessed the smallest particle size (mean particle size of 119 nm) and the highest DEB conversion of 79.16% under the reaction conditions: 260 °C, 4.0 MPa, WHSV (diethylbenzene) of 2.0 h−1, W(benzene)/W(diethylbenzene) of 3/1, time on stream of 5 h. Then, to elucidate the catalytic roles of acid sites with different strengths, types and positions in beta zeolite in the transalkylation reaction, we carried out Na+ loading on the prepared beta zeolite to eliminate strong acid sites and poisoned the Brønsted acid sites and external acid sites by using 2,4-dimethylquinoline (2,4-DMQ) and triphenylphosphorus (TPP) as toxic reagents, respectively. The results suggested that the moderate and strong Brønsted acid sites of beta-IMD0.5 were the active sites for the liquid-phase transalkylation of DEB with Bz and their utilization rate showed a trend of increasing first and then decreasing. Significantly, 31% of the external Brønsted acid sites of beta-IMD0.5 contributed 81% of DEB conversion. The external acid sites had more contribution to the reaction due to the short diffusion path and fine accessibility.
研究领域:
催化化学
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材料科学
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DOI
高影响因子
BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY
·
2010
·Vol. 86
·期 1
·38-42
·
IF 0.992
Yang Zhong-Zhi,Li Yong-Fang,Li Zhi-Chun,Gu Yu-Mei,Zhu Ya,Zhang Zhan-Jun
Five higher Chlorinated Benzenes (CBs), include Hexachlorobenzene (HCB), pentachlorobenzene (PeCB) and three isomers of tetrachlorobenzens, were analyzed in 20 outdoor dust samples collected from a fast developing city, Xinxiang. Only HCB was detected in all outdoor dust samples. The dominate part of the CBs residue in most samples was HCB and the mean HCB concentration (4.13 ng/g dry weight) in this study was in the range of global background soil HCB levels (ranging from 0.010 to 5.20 ng/g dry weight). The higher ratios of HCB/PeCB in the outdoor dust samples in the present study indicate that pesticide application may be an important source of HCB in China.
研究领域:
环境科学
·
毒理学
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DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
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2020
·
IF 5.065
Hong Li,Yuhao Zhang,Dexin Sun,Liang Zhao,Jinsen Gao,Chunming Xu
In order to investigate the ability of N -methyl-2-pyrrolidone (NMP) to extract aromatics (benzene, toluene) and sulfides (3-methylthiophene, thiophene) from n-hexane, the liquid-liquid equilibrium (LLE) data of n-hexane + {benzene, toluene, thiophene or 3-methylthiophene} + NMP systems were determined at 293.15 K under 101.3 kPa. The Othmer-Tobias and Hand equations were applied to validate the reliability of the obtained LLE data, and the correlation coefficients ( R 2 ) are close to unity. It was found that sulfides could be successfully extracted from n-hexane by NMP solvent companying with the extraction of aromatics. However, the separation factors and distribution coefficients of the sulfides are greater than those of aromatics, indicating that the sulfides are more easily extracted by NMP. Furthermore, the separation energies of the sulfides are greater than that of aromatics, which is also a piece of evidence for easier separation of sulfides. In order to extend those results to other extraction processes involving those sulfides, aromatics and solvent, the binary interaction parameters of the NRTL and UNIQUAC thermodynamic models were calculated by correlating the LLE data. The RMSD values were all <0.0070, and a graphical user interface based on the Gibbs tangent plane test was also applied to validate the coherent consistency of the parameters. The results show that the obtained binary interaction parameters could be reliable adopted in the design and optimization of the related extraction/separation process in industry.
研究领域:
化学工程
·
环境科学
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DOI
高影响因子
CHINESE JOURNAL OF CATALYSIS
·
2024
·
IF 15.7
Kui Jin,Meiyun Zhang,Penghua Che,Dongru Sun,Yong Wang,Hong Ma,Qiaohong Zhang,Chen Chen,Jie Xu
ABSTRACT Hydrogen bonding is a fascinating interaction that controls the outcomes of chemical reactions. However, overcoming the strong deactivation arising from alterations in the polarity and electronic properties of the reactants and intermediates remains a challenge. Herein, we proposed a “solvent-scissors” strategy for overcoming the inert hydrogen bonding, enabling the efficient aerobic oxidation of methyl aromatics into aromatic acids under atmospheric oxygen at 25–45 °C. The hydrogen bonds between the key intermediate, benzaldehyde (PhCHO), and hexafluoroisopropanol (HFIP) were reconstructed using solvent-scissors (acetic acid (HOAc), ethyl acetate, ethyl chloroacetate , and methyl chloroacetate), which promoted the release of free PhCHO from its inert hydrogen-bonded state and enabled the one-step oxidation of toluene to benzoic acid under mild conditions. The standard Gibbs free energy changes (Δ G 0 ) representing the proton acceptance capability of the solvent were of the same order of magnitude as the turnover number (TON) (capacity for promoting benzaldehyde oxidation). This approach affords remarkable benzoic acid selectivity (98.7%) with high toluene conversion (96.8%) at 45 °C within 4 h under 0.1 MPa O 2 using NHPI/metal acetate/HFIP-HOAc. This strategy opens up a new avenue for regulating hydrogen bonding in a wider range of applications for the planning and development of synthesis protocols.
研究领域:
有机化学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子