INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2014
·
IF 2.235
Nan Li,Fang Wang,Zhiqing Zhang,Huihui Nie,Chengcheng Ren,Mei Cui
Polymeric 1-vinyl-3-ethylimidazolium tetrafluoroborate ionic liquids modified microspheres of silica gel were prepared by free radical polymerization in toluene. Characterization with Fourier transform infrared (FTIR), elemental analysis, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), gel permeation chromatography (GPC), thermogravimetric analysis (TGA), and 13C, 29Si magic angle spinning (MAS) nuclear magnetic resonance (NMR) demonstrated that 1-vinyl-3-ethylimidazolium tetrafluoroborate had successfully loaded on the surface of silica gel and formed a stable polymer coating. Furthermore, to detect the potential desulfurization performance, a series of experiments of model fuel desulfurization with polymeric ionic liquid modified silica gel had been carried out. The desulfurization efficiency of modified silica gel was investigated by removing 2-methylthiophene, benzothiophene, and dibenzothiophene from model fuel (n-heptane/2-methylthiophene, benzothiophene, and dibenzothiophene) under tested conditions. It was shown that the modified silica gel exhibited remarkable desulfurization capacity for aromatic S-containing compounds and the sulfur removal selectivity followed the order of 2-methylthiophene < benzothiophene < dibenzothiophene due to the different density aromatic π-electrons.
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CHINESE JOURNAL OF POLYMER SCIENCE
·
2014
·Vol. 32
·期 11
·1550-1563
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IF 1.42
Yan Hua,Lu Chun-xiang,Jing De-qi,Hou Xiang-lin
Chemical degradation of diglycidyl ether of bisphenol A (DGEBA) epoxy resin cured with an aliphatic amine in supercritical 1-propanol was investigated under different reaction temperature and time. The combination of GC-MS and LC-MS proved that the epoxy resin was decomposed to five main products including phenol, 4-isopropylphenol, 4-isopropenylphenol, bisphenol A, and 4,4′-(cyclopropane-1,1-diyl)diphenol. The 13 C-NMR results verified the chemical structures of the degradation products. The change of the products’ yield with time was evaluated by an effective means of HPLC. In addition, the GPC analysis confirmed the formation of soluble low molecular weight clusters during the degradation reaction. A possible free-radical reaction mechanism was proposed for chemical depolymerization of the epoxy resin in supercritical 1-propanol. After the homolytic cleavage of the aromatic ether linkages, the resulting bisphenol A biradical either produced 4,4′-(cyclopropane-1,1-diyl)diphenol after intramolecular rearrangement or generated bisphenol A after capturing hydrogen from 1-propanol.
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FLUID PHASE EQUILIBRIA
·
2014
·
IF 2.241
Fufeng Cai,Jessica Juweriah Ibrahim,Lijing Gao,Ruiping Wei,Guomin Xiao
Methanol and dimethyl carbonate (DMC) mixture is present in the industrial manufacturing process of DMC, which is made from the catalytic oxidative carbonylation of methanol. The separation of methanol and DMC is important but difficult due to the formation of an azeotropic mixture. This work has been focused on a study of phosphoric-based ionic liquids (ILs) as green solvents for the separation of methanol and DMC in the extraction process. The knowledge of liquid–liquid equilibrium (LLE) of this mixture is essential for the design of the extraction separation process. For this reason, LLE data for the ternary systems {methanol + DMC + 1-methyl-3-methylimidazolium dimethylphosphate ([MMIM][DMP])} and {methanol + DMC + 1-ethyl-3-methylimidazolium diethylphosphate ([EMIM][DEP])} were measured at T = (298.2 and 313.2) K and atmospheric pressure. The solute distribution ratio and selectivity of the methanol, derived from the tie-lines data, were calculated and analyzed in order to evaluate the capacity of the studied ILs as solvents in liquid extraction process. The experimental results show that the values of selectivity for the studied ILs follow this order: [MMIM][DMP] > [EMIM][DEP]. Finally, the experimental LLE data for the studied ternary systems were compared with the calculated values obtained by means of the non-random two liquid (NRTL) model. The NRTL model was verified to accurately correlate the experimental LLE data.
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RSC Advances
·
2014
·Vol. 4
·期 71
·37470-37478
·
IF 3.708
Jianxiong Xu,Weiwei Liu,Yunfei Yu,Jingjing Du,Na Li,Lijian Xu
A simple synthesis of mesoporous silica nanoparticles with cubic Pmn pore structure (SBA-1) and controlled pore size is reported. The synthesis of mesoporous silica nanoparticles is achieved by employing organic mesomorphous complexes of polyelectrolyte (poly(acrylic acid)) and cationic surfactant (hexadecyl pyridinium chloride) as template, and tetrapropoxysilane as silica source. It is found that the pore size of the synthesized mesoporous silica nanoparticles can be tuned by the incorporation of 1,3,5-trimethylbenzene. By adjusting the amount of 1,3,5-trimethylbenzene in the synthesis, a series of silica nanoparticles with controlled pore size ranging from 2.5 nm to 5.3 nm is obtained. The adsorption properties of the mesoporous silica nanoparticles with different pore size against lysozyme are compared. The results show that mesoporous silica nanoparticles with proper pore size and well ordered pore structure benefit the adsorption and exhibit a low leaching rate.
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JOURNAL OF STRUCTURAL CHEMISTRY
·
2015
·Vol. 56
·期 3
·458-462
·
IF 0.508
Huang Q. -W.,Liu S. -G.,Li G. -B.,Wang S. -X.,Su W. -Y.,Liang D. -M.,Mao S. -Q.
A new complex Cu(bpbp)Cl 2 ·DMF·H 2 O is synthesized by treatment of CuCl 2 with 2,6-bis(1-phenylbenzimidazol-2-yl)pyidine in DMF. Its structure is characterized by elemental, IR, UV, and single crystal X-ray structure analyses. For the complex: crystal system, triclinic, space group \(P\bar 1\) , a = 1.0537(1) nm, b = 1.1735(1) nm, c = 1.3749(2) nm, α = 112.275(2)°, β = 91.531(2)°, γ = 97.700(2)°, V = 1.553(4) nm 3 , Z = 2. In a distorted trigonal bipyramidal geometry the Cu(II) ion is coordinated by three nitrogen atoms from 2,6-bis(1-phenylbenzimidazol-2-yl)pyridine and two chloride ions. The antiproliferative activities of the complex are screened by MTT assay against HepG2, Huh7, Eca109, and Eca9706 cancer cells. The complex exhibits specific inhibition on Eca9706 cancer cells with the IC 50 value of 28 μM after 48 h treatment. CCDC: 968927.
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RSC Advances
·
2015
·Vol. 5
·期 35
·27901-27911
·
IF 3.84
Chunling Xin,Haijuan Zhan,Xin Huang,Hongguang Li,Ning Zhao,Fukui Xiao,Wei Wei,Yuhan Sun
Two type of modulators, including sodium acetate and triethylamine were used to synthesize nanosized HKUST-1 crystals with tailored size and morphology using a coordination modulation method. The results of X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and N2 sorption isotherms confirm that the size of the HKUST-1 crystals can be tuned from the micron scale to the nanoscale through precise modulation of the amounts of the modulators. Moreover, hierarchical porous structures are obtained with the addition of modulators. It is suggested that a moderate acid–base environment and capping groups play an important role in controlling the size and morphology of HKUST-1. Dynamic CO2 breakthrough experiments illustrate that the CO2 capacity of nanosized HKUST-1 crystals is superior to that of micron-sized HKUST-1 crystals under low CO2 partial pressure conditions (0.1 bar). Besides, the CO2 adsorption capacity of nanosized HKUST-1 crystals was maintained after ten adsorption/desorption cycles.
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CARBOHYDRATE POLYMERS
·
2015
·
IF 4.074
Cong Chen,Yan Meng,Sheng Li,Wenhua Wu,Chuanjun Liu,Xiaojuan Xu,Lina Zhang
A polysaccharide coded as PR-CA was extracted from Polyporus rhinoceros and determined to be a β-(1→3)- d -glucan with multiple branches. The weight-average molecular weights ( M w ) of PR-CA in dimethylsulfoxide (DMSO) and in water were determined with static light scattering (SLS) to be 3.57 × 10 5 and 1.79 × 10 7 , indicating existence of the single chains in DMSO and co-existence of single chains and aggregates in water. Moreover, the stiffness of single chains of PR-CA in water was directly visualized by atomic force microscopy (AFM) and transmission electron microscopy (TEM). The hollow structure of PR-CA nanofibers with width of 30–40 nm and length of ∼350 nm formed in the water/DMSO (9:1, v:v) was demonstrated by a fluorescent probe tetraphenylethylene (TPE) via aggregation-induced emission (AIE). The formation of PR-CA nanofibers was ascribed to the parallel aggregation of the extended PR-CA chains due to the hydrogen bonding and hydrophobic interaction. This work offered valuable results for promising applications of natural branched β-glucans in the biological fields of drug inclusion, delivery and disease diagnosis.
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PubMed
高影响因子
Soft Matter
·
2014
·Vol. 11
·期 7
·1293-1302
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IF 4.151
Yiyang Kong,Binjie Hu,Kwang-Leong Choy,Xiaoyu Li,Guangdi Chen
Room temperature ionic liquids (RTILs) are non-volatile organic salts, and few of them with low melting point may replace the conventional coalescing agents in waterborne coatings, thus preventing volatile organic compounds (VOCs) emission, caused by coalescing agents. The formation of waterborne coating containing RTILs can be achieved by the encapsulation of RTILs inside latexes via miniemulsion polymerization. Achieving a stable miniemulsion is a crucial step for further polymerization. In this study, 1-octyl-3-methylimidazolium hexafluorophosphate (C8mimPF6) was chosen, and various factors which might affect droplet size and its stability, including surfactant type, surfactant concentration, and C8mimPF6 concentration, were investigated. It was found that the presence of a small amount of C8mimPF6 coupled with the surfactant would offer marked effects on the droplet size reduction and droplet stability. Such effect may reach its maximum from 1 to 5 wt% C8mimPF6. Above the critical concentration, adding more C8mimPF6 to the oil phase may cause a larger initial droplet size as well as weaken the droplet stability. Such observations were consistent with the zeta potential measurements for miniemulsions prepared under similar conditions.
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PubMed
高影响因子
Catalysis Science & Technology
·
2014
·Vol. 4
·期 11
·4010-4019
·
IF 4.76
Chao Lin,Kai Tao,Hongbo Yu,Dayin Hua,Shenghu Zhou
Molybdenum-doped mesoporous SBA-15, mesoporous SBA-15-supported MoO3/SBA-15, and traditional silica-supported MoO3/SiO2 were successfully synthesized. Various techniques, such as XRD, TEM, BET, UV-DRS, Raman, XPS and IR, were used to characterize the above obtained materials. The studies of TEM, XRD and BET confirmed that the highly ordered mesoporous structure of SBA-15 was maintained in the doped Mo-SBA-15 whereas supported MoO3/SBA-15 showed a significant reduction in surface area due to the deposition of MoO3 nanoparticles into the SBA-15 channels. XPS studies revealed that a high concentration of Mo5+ species appeared in doped Mo-SBA-15 whereas supported MoO3/SBA-15 and MoO3/SiO2 only contained Mo6+ species. The metathesis reaction of 1-butene and ethene to propene was used to evaluate the catalytic performance of Mo-containing materials. The doped Mo-SBA-15 illustrated a superior catalytic performance over the supported MoO3/SBA-15 and MoO3/SiO2 catalysts. The enhancement of catalytic performance for doped Mo-SBA-15 was assigned to the incorporation of Mo species into the SBA-15 framework. Due to the doping method, Mo-SBA-15 exhibited a well-ordered mesoporous structure, a high surface area, and a high concentration of Mo5+ species, which is beneficial to the catalytic performance for metathesis reactions.
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JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2017
·
IF 2.323
Huanhuan Sun,Cheng Liu,Zhongfeng Geng,Yang Lu,Yixuan Chen
In this article, isobaric vapor–liquid equilibrium (VLE) data for three binary systems of acetaldehyde + ethanol, acetaldehyde + ethyl acetate, and acetaldehyde +1-butanol were determined using a modified Rose–Williams equilibrium still at 101.3 kPa. The experimental data were confirmed by the area method of Herington and point-to-point method of Van Ness. Activity coefficient models, Wilson, NRTL, and UNIQUAC were employed to correlate the experimental VLE values. Both models showed a good agreement and the binary interaction parameters were estimated.
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CHEMICAL ENGINEERING JOURNAL
·
2017
·
IF 6.216
Guoqiang Wu,Zhengguo Lin,Liang Li,Lei Zhang,Yanping Hong,Wenjun Wang,Chao Chen,Yan Jiang,Xianzai Yan
An efficacious approach to improve the catalytic performance of titanium silicalite-1 (TS-1) catalysts in epoxidation of allyl chloride with hydrogen peroxide has been developed. A series of modified TS-1 catalysts were prepared by corroding the classic TS-1 catalyst with different concentrations of tetrapropyl ammonium hydroxide (TPAOH) under controlled conditions. The resultant catalyst samples were characterized by XRD, ICP, N 2 -adsorption, FT-IR, UV–vis, SEM and TEM. The catalytic activity of the modified TS-1 catalysts is significantly improved, which could be attributed to the increase of the mesopore volume and pore diameter and decrease of the diffusion limitation but without obvious changes of the framework structure, framework Ti content, the outer surface shape and crystal size of the modified TS-1. Furthermore, the kinetics of the epoxidation of allyl chloride over TS-1-0.05 catalyst was also systematically studied, the apparent orders of reaction with respect to H 2 O 2 and allyl chloride are 0.68 and 0.62, respectively, and the activation energy of the epoxidation reaction on the TS-1-0.05 catalyst is 57.4 kJ mol −1 .
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JOURNAL OF CHEMICAL THERMODYNAMICS
·
2016
·
IF 2.196
Hujun Xie,Lijiang Zhao,Chengcheng Liu,Yifan Cao,Xiaoxing Lu,Qunfang Lei,Wenjun Fang
The densities of aqueous solutions of glycine, l -serine, l -alanine, l -proline with the ionic liquid (IL), 1-phenylpiperazinium tetrafluoroborate ([Phpi][BF 4 ]) at the IL concentrations of (0.025, 0.055 and 0.100) mol·kg −1 have been measured at the temperatures of (298.15, 303.15 and 308.15) K. On the basis of the experimental results, the apparent molar volume ( V Ф ), standard partial molar volume ( V Ф 0 ), transfer partial molar volume (Δ tr V Φ 0 ) and hydration number ( n H ) have been calculated. The hydrophilic–hydrophilic, hydrophobic–hydrophilic and hydrophobic–hydrophobic interactions are involved in the studied systems of {[Phpi][BF 4 ] + amino acids + H 2 O. These volumetric parameters can help to understand the mixing effects and other complex biological processes between amino acids and ionic liquid aqueous solution.
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危险品化学品经营许可证（带存储）