JOURNAL OF CATALYSIS
·
2018
·
IF 6.759
Tianyu Gao,Jing Chen,Wenhao Fang,Qiue Cao,Weiping Su,Franck Dumeignil
Mn-Ce mixed oxides-supported Ru nanoparticles (Ru/Mn X Ce 1 O Y ) with enhanced oxygen mobility and strong metal-support interaction were prepared and applied to the aerobic oxidation of 5 -hydroxymethylfurfural (HMF) to 2,5 -furandicarboxylic acid (FDCA) without addition of any base additives. Oxygen and water were used as green oxidant and solvent, respectively. The catalysts were characterized in depth by XRD, H 2 -TPR, O 2 -TPD, UV–Vis DRS, XPS and TEM, to reveal materials properties from bulk to surface. The influence of Mn/Ce molar ratios in support materials and reaction parameters ( i.e. , HMF/Ru ratio, O 2 pressure, reaction temperature and time) was systematically studied and optimized. The reaction route and rate-determining step for oxidation of HMF to FDCA over the Ru/Mn X Ce 1 O Y catalysts were investigated by kinetic analysis. Well-dispersed metallic Ru nanoparticles with a mean size of 4.4 nm deposited on the support were found essential to activate and oxidize the HMF molecule. The Mn/Ce molar ratio was found to affect not only conversion of HMF but also distribution of products. The Ru/Mn 6 Ce 1 O Y catalyst demonstrated an exceptional yield (≥99%) of FDCA, which corresponds in our conditions to one of the best productivity (5.3 mol FDCA ·mol Ru −1 ·h −1 ) ever reported in literature. The superior activity of the Ru/Mn 6 Ce 1 O Y catalyst was mainly associated with (i) the strong metal-support interaction and (ii) the synergistic effect between manganese and cerium oxides. This catalyst showed the highest surface concentrations in Mn 4+ and Ce 3+ among the series, which, as a consequence, enhanced the availability and mobility of active oxygen species. This catalyst was shown resistant to deactivation during eight recycling uses thanks to a strong metal-support interaction between Ru nanoparticles and the Mn-Ce mixed oxide used as a support.
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2018
·
IF 11.698
Hui-Fang Ye,Rui Shi,Xiao Yang,Wen-Fu Fu,Yong Chen
Photocatalytic water splitting over semiconductors without using of any electron sacrificial agents is essential to the conversion of solar energy into chemical energy. Herein, we report remarkable photocatalytic hydrogen production from pure water without the assistance of electron sacrificial agents by using P-doped Zn x Cd 1−x S with rich S vacancies (Zn x Cd 1−x S-P) as the photocatalyst. It is found that interstitial P doping in Zn x Cd 1−x S solid solutions with rich S vacancies can prolong the lifetime of charge carriers and enhance the generation and separation of photogenerated electrons-holes, resulting in a H 2 evolution rate of up to 419 μmol h −1 g −1 , which is 72 and 7.5 times higher than those of ZnS-P (5.8 μmol h −1 g −1 ) and CdS-P (56 μmol h −1 g −1 ), respectively. Furthermore, the introduction of biomass-derived compound 5-hydroxymethylfurfural (HMF) into this system further promotes the photocatalytic hydorgen evolution reaction and simultaneously obtains value-added HMF oxidation products.
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2018
·
IF 4.908
Wenfeng Zhao,Weibo Wu,Hu Li,Chengjiang Fang,Tingting Yang,Zhongwei Wang,Chao He,Song Yang
Quantitative production of 2,5-bis(hydroxymethyl)furan (BHMF) was achieved at room temperature (25 °C) via highly selective hydrogenation of biomass-derived 5-hydroxymethylfurfural (HMF) employing alkali salt KF as catalyst and polymethylhydrosiloxane (PMHS) as hydrogen source. A moderate turnover frequency (TOF: 4.2 h −1 ) was observed for this mild and sustainable reaction process. Moreover, a combination of Amberlyst-15 with KF could successfully catalyze the direct synthesis of BHMF from hexose sugars such as fructose and inulin via tandem dehydration and hydrogenation in a single pot. This catalytic system is more selective compared with H 2 -participated counterpart, giving a high BHMF yield and selectivity of up to 98% and >99% from HMF, respectively. Moreover, the catalytic performance of KF could remain for at least five consecutive cycles in the conversion of HMF to BHMF.
✓ 已验证
产品关联
DOI
高影响因子
FIBERS AND POLYMERS
·
2018
·Vol. 19
·期 7
·1363-1372
·
IF 1.353
Fu Yifan,Teng Yun,Yu Guomin,Yin Cuiyu
Unmodified polyamide 6 commonly dyed with acid dyes, and has no flame-retarded properties. So they are flammable and can be easily stained by foods or drinks that contain acid dyes. However, the acid groups react with amino groups that existed at the end of PA6 chain while using cationic dyes. Thus, the acid dyes can be washed immediately. In this study, the flame retardant and cationic dyeable polyamide 6 (FRCD-PA6) modified with 5-sulfoisophthalic acid sodium (5-SSIPA) and melamine cyanurate (MCA) was successfully prepared by the two-step-melt polymerization method. Firstly, cationic dyeable polyamide 6 (CD-PA6) was prepared with sodium salt from 5-sulfoisphthalic acid. Secondly, melamine cyanurate, as an efficient flame retardant, was blended into the reaction. The chemical and crystalline structures of FRCDPA6 were characterized by the Fourier transform infrared spectroscopy (FT-IR) and wide angle X-ray diffraction (XRD). Their thermal properties were tested by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), and morphology was analyzed by SEM, respectively. It had been measured to prove the dispersion of 5-SSIPA and MCA on polyamide 6 matrix. Incorporating with 5-SSIPA created more amorphous regions and rose up the dyeing rate easily, with a highest dyeing rate for about 96.79 %. The effect of varying MCA content on the composites showed more flame retardant and made better heat-resistance. Moreover, with the appropriate addition of MCA content, the limit oxygen index (LOI) reached up to 27, less smoking, no more black smoke, droplet phenomenon was slightly, and flame resistance had greatly improved. Because of the good synergy between 5-SSIPA and MCA, a kind of novel modified polyamide 6 which own both cationic dyeable and efficient flame retardant properties was born.
✓ 已验证
产品关联
DOI
高影响因子
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
·
2018
·Vol. 2019
·期 1
·51-58
·
IF 2.507
Hangle Guo,Tongguang Ge,Jian Lv,Changlin Du,Jian Zhou,Zhicheng Liu,Zile Hua
Graphical A facile and eco-friendly mesoporogen-free steam-assisted crystallization strategy has been developed for the synthesis of hierarchically structured ZSM-5 zeolites with superior MTP catalytic performance, and a new “in situ alkali etching-hydrothermal restoring“ mechanism is discussed. A series of hierarchically structured ZSM-5 zeolites (ZSM-5 HSZs) with a Si/Al ratio of about 200 have been successfully synthesized in the absence of additional mesoporous agents. XRD, N 2 sorption isotherms, SEM, TEM and NH 3 -TPD results showed that the obtained HSZs materials possess high crystallinity, interconnected micro/mesoporous structures and similar total acid amounts. Meanwhile, in the methanol-to-propylene (MTP) reaction, compared to the microporous counterpart, all synthesized ZSM-5 HSZs demonstrated superior performance benefitting from their hierarchical porous structures. Interestingly, 27 Al MAS NMR and Py-FTIR results confirmed the inter-transformation of framework and extra-framework Al species with the extension of materials crystallization duration and consequently the variation of materials surface acidity. As a result, the optimized catalyst achieved the highest initial propylene selectivity of 54.4 % and the longest catalyst lifetime ( t 90 ) of 175 h under the weight hourly space velocity (WHSV) of 1.0 g g –1 h –1 . Moreover, a new “in situ alkali etching-hydrothermal restoring“ mechanism has been proposed to elucidate the structural evolution of here reported high-silica ZSM-5 HSZs during the synthesis.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2018
·
IF 2.196
Yongzhao Zhang,Xia Guo,Jian Xu,Yuxiang Wu,Meizhen Lu
Liquid–liquid equilibrium (LLE) data was very important for the process design and optimization of 5-hydroxymethylfurfural (5-HMF) production. To provide this fundamental data, experimental liquid–liquid equilibrium data for ternary systems, {water + 5-HMF + 1-butanol}, {water + 5-HMF + isobutanol}, and {water + 5-HMF + methyl isobutyl ketone}, were measured at 313.15, 323.15, and 333.15 K. Partition coefficients were used to assess the extraction capacity of organic solvents in the biphasic systems. 1-Butanol and isobutanol were desirable extractants with good extraction performance and environmental benign properties. The NRTL model was used to correlate the experimental data and the binary interaction parameters were obtained. The average relative deviation was lower than 10%.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
·
2018
·
IF 2.631
Sheng Zhang,Xiaxia Song,Guowei Lin,Qi Yang,Quan Shi,Hui Zheng,Xin Liu,Qing Wei,Gang Xie,Sanping Chen,Shengli Gao
In this paper, two new H 2 ZTO-Co(II) coordination polymers (H 2 ZTO = 4,4′-azo-1,2,4-triazol-5-one), [Co(H 2 ZTO) 2 (H 2 O) 4 ](NO 3 ) 2 (1) and {[Co(H 2 ZTO)(H 2 O) 4 ](NO 3 ) 2 ·2H 2 O} n (2), have been synthesized and characterized. Polymer 2 is derived from 1 and undergoes a multistage transformation by soaking 1 in distilled water. X-ray single crystal structure analyses showed that 2 exhibit a one-dimensional (1D) chain geometry coordinated by 0D units of 1 through uncoordinated nitrogen atoms of H 2 ZTO ligands. The thermal decomposition behaviors and magnetic properties of 1 and 2 were discussed. In addition, the low-temperature (1.9–300 K) heat capacities of 1 and 2 were measured using the heat capacity option of a Quantum Design Physical Property Measurement System (PPMS). The thermodynamic functions of 1 in the experimental temperature range were derived by fitting the heat capacity data to a series of theoretical and empirical models. Using the fitted heat capacity results, the standard molar entropy and standard molar enthalpy have been respectively calculated to be (871.1 ± 8.7) J·mol −1 ·K −1 and (132.7 ± 1.3) kJ·mol −1 for 1 .
✓ 已验证
产品关联
DOI
高影响因子
CRYSTENGCOMM
·
2019
·Vol. 21
·期 34
·5095-5105
·
IF 3.382
Xia-Lin Dai,Alexander P. Voronin,Wei Gao,German L. Perlovich,Tong-Bu Lu,Jia-Mei Chen
5-Fluorouracil (5FU) is a BCS class III drug with good aqueous solubility and poor permeability, which severely limits its transdermal permeation through the stratum corneum. Herein, four cocrystals of 5FU with a series of isomeric hydroxybenzoic acids, including salicylic acid (2 : 1), 3-hydroxybenzoic acid (1 : 1) and 4-hydroxybenzoic acid (forms I and II, 1 : 1) were prepared and subjected to membrane permeation. They exhibited significantly improved membrane permeability due to the lipid solubility enhancement caused by cocrystallization. Solid-state DFT computations followed by Bader analysis based on single crystal structures were carried out to quantify the pattern of non-covalent interactions in the cocrystals. The lattice energy values were estimated as a sum of energies of non-covalent intermolecular interactions, which show a negative correlation with the lipid solubility of 1 : 1 cocrystals. This study has important implications for the use of the cocrystallization approach to improve the permeability of transdermal drugs.
✓ 已验证
产品关联
DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
·
2019
·
IF 4.507
Lele Jin,Wenzhi Li,Qiying Liu,Longlong Ma,Song Li,Yang Liu,Baikai Zhang,Qi Zhang
The liquid fuel (made of C 5 /C 6 alkanes) was obtained directly from the hydrogenolysis of microcrystalline cellulose (MCC) with Ir-VO x /SiO 2 combined with HZSM-5 as the composite catalyst in a biphasic system (n-dodecane + H 2 O). The performance of the catalyst was investigated by carrying out a series of experiments using various V/Ir molar ratios , catalyst dosages, reaction temperatures, reaction time, hydrogen pressure and substrates. At the optimized conditions, the cellulose was almost completely converted, and at the same time, a high C 5 /C 6 yield of 85.1% was obtained at 210 °C for 24 h and 6 MPa with the V/Ir molar ratio being 0.13. These results not only proved that Ir-VO x /SiO 2 (V/Ir = 0.13) has excellent performance for the hydrogenolysis of MCC to liquid alkanes, but also indicated that vanadium is a good metal promoter for iridium . In addition, it was proven the C5/C6 alkanes were obtained via sorbitol through the combined effect of Ir-VO x /SiO 2 and HZSM-5.
✓ 已验证
产品关联
DOI
高影响因子
FIBERS AND POLYMERS
·
2017
·Vol. 18
·期 12
·2476-2480
·
IF 1.113
Hao Youwei,Zhao Jie,Wang Gang,Cao Liqin,Wang Jide,Yue Fan
Mesocellular silica foam (MCF) grafted with thermo-responsive and pH-responsive copolymer poly( N -isopropylacrylamide- co -acrylic acid), was prepared by precipitation polymerization using supercritical carbon dioxide (scCO 2 ) as entrainer and solvent. Vinyl-functionalized MCF was first synthesized through post-synthesis via using vinyltriethoxysilane as a coupling agent for surface modification. Entrapped monomers of N-isopropylacrylamide (NIPA) and acrylic acid (AA) were then introduced and assembled onto the vinyl-modified MCF with the aid of scCO 2 . The grafting copolymer performed here as an on/off switch in the release of 5-fluorouracil, as confirmed by using UV-visible absorption spectroscopy. The grafted organic content and drug loading efficiency were 65.2 wt% and 11.5 wt%, respectively. The resultant grafting composite showed potential for application in drug delivery and exhibited thermo- and pH-responsiveness to external environmental changes.
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2024
·
IF 20.2
Jianfeng Shan,Zheng Chen,Dengfeng Wang,Guangyu Zhang,Sheng Li,Chuan Sun,Dongchao Wang,Caixia Ju,Xuelan Zhang,Lei Li
Catalytic conversion of ethyl levulinate (EL) to γ-valerolactone (GVL) is a pivotal reaction in biomass conversion. Here, Pd/CoO x was studied and showed much higher EL hydrogenation reactivity than other Pd based catalysts. Further investigation revealed that EL conversion increased linearly with PdCo alloying degree elevating, indicating that PdCo alloy is ascribed to the superior reactivity of Pd/CoO x . Interestingly, Pd/CoO x with low Pd loading also exhibited excellent hydrogenation performance, and surface enrichment of Pd was identified as the main reason. Additionally, employing HZSM-5 as a co-catalyst not only accelerated ethyl 4-hydroxypentanoate lactonization, but also dramatically improved the stability of Pd/CoO x . As a result, a 99.1 % yield of GVL was achieved by the synergistic catalysis of HZSM-5 and Pd/CoO x containing 0.58 wt% Pd, which is comparable with the best catalyst ever reported in alkyl levulinate hydrogenation to GVL. Furthermore, the insights gained from this work have broad potential applications in biomass hydrogenation.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2024
·
IF 9.4
Yumei Zhu,Jinlv Wei,Jia Wu,Rong Chen,Panagiotis Tsiakaras,Shibin Yin
The development of catalysts with suitable adsorption behavior for the reaction molecules and the elucidation of their internal structure-adsorption-catalytic activity relationships are crucial for the electrooxidation of 5-hydroxymethylfurfural (HMF). In this work, NiO-CuO heterostructures with a spontaneous built-in electric field (BEF) are specifically designed and used to regulate the OH − adsorption site for freeing up the active site of HMF for the HMF oxidation reaction (HMFOR). The mechanism driving electron pumping/accumulation of the BEF is examined by X-ray photoelectron spectroscopy (XPS) and ultraviolet photoelectron spectroscopy (UPS). Electrochemical data and theoretical calculations show that BEF modulates the adsorption energy and adsorption site of substrate molecules, thereby enhancing the performance of HMFOR and hydrogen evolution reaction (HER). Notably, the NiO-CuO electrode demonstrates high 2,5-Furandicarboxylic acid (FDCA) selectivity (99.76 %) and generation rate (13.79 mmol gcat −1 h −1 ). It only requires 1.33 V to obtain a current density of 10 mA cm −2 for HMFOR-coupled H 2 evolution. This research introduces a novel approach by regulating the adsorption of reactive molecules for HMFOR-assisted H 2 evolution.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）