JOURNAL OF MOLECULAR LIQUIDS
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2017
·
IF 3.648
Junwei Zhang,Hang Li,Xiao Ma,Huanxin Li,Shuai Yang,Li Xu,Guoji Liu
The solubility of 1,6-Hexanediol in (ethyl acetate + methanol) and (ethyl acetate + n-butanol) binary solvents was determined by isothermal saturation method at atmospheric pressure of 101 kPa. The solubility of 1,6-Hexanediol in the two binary solvents increases with the increase of temperature at fixed mass fraction of ethyl acetate from 278.15 K to 298.15 K, and decreases with the increase of mass fraction of ethyl acetate at fixed temperature. In addition, experimental solubility data were correlated by modified Apelblat equations, Jouyban-Acree model and Sun model. Furthermore, the standard dissolution enthalpy was calculated.
研究领域:
物理化学
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热力学
✓ 已验证
产品关联
DOI
高影响因子
ACS Catalysis
·
2025
·
IF 13.1
Shihao Su,Guojun Lv,Jialing Shen,Fuxin Wang,Lachgar Oussama,Yan Chen,Shengnan Xu
In the tandem synthesis of 1,2-cyclohexanediol, solvents such as acetonitrile are often added to eliminate the immiscibility of cyclohexene with water and accordingly strengthen the interphase mass transfer; however, the usage of solvents artificially increases the solvent separation procedure, enhancing the energy consumption and decreasing the economic benefits of the reaction process. Hence, the development of the solvent-free Pickering interfacial tandem catalysis of cyclohexene to 1,2-cyclohexanediol is extremely appealing. In this study, β-MnO2 and Mn2O3 were prepared by calcining γ-MnO2 synthesized with the hydrothermal synthesis method and concurrently served as a colloidal emulsifier and a heterogeneous catalyst in the Pickering interfacial tandem catalysis of cyclohexene to 1,2-cyclohexanediol at room temperature in the presence of the oxidant molecular oxygen and the co-oxidant isobutyraldehyde. The prepared β450-MnO2 sample revealed the best tandem catalysis performance, achieving a cyclohexene conversion of 99.4% and a 1,2-cyclohexanediol selectivity of 83.6% within 4 h of reaction, which can be ascribed to the highest Mn4+/Mn3+ ratio and the greatest concentration of oxygen vacancies as well as the most stable Pickering emulsion. At the same time, density functional theory (DFT) studies further confirmed that isobutyraldehyde and molecular oxygen could be more easily adsorbed and activated by β450-MnO2 in comparison with the other catalyst samples, benefiting its eminent catalytic epoxidation performance. In addition, a possible reaction mechanism for the β450-MnO2 catalyst catalyzing cyclohexene into 1,2-cyclohexanediol in the Pickering interfacial tandem catalytic reaction system was put forward and validated through quenching experiments as well as in situ infrared characterization. The synthesized β450-MnO2 catalyst exhibited reusability for greater than 5 cycles, and meanwhile, the Pickering interfacial tandem catalytic reaction system can be expanded to a spread of linear and cyclic alkene substrates, highlighting the superiority of the β450-MnO2 catalyst. These findings verify that the synthesized β450-MnO2 catalyst is capable of being utilized as an efficient and stable catalyst for the Pickering interfacial catalytic conversion of alkenes into 1,2-diols at room temperature.
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
Science China-Chemistry
·
2017
·Vol. 60
·期 7
·920-926
·
IF 4.132
Li Yan,Cheng Haiyang,Zhang Chao,Zhang Bin,Liu Tong,Wu Qifan,Su Xinluona,Lin Weiwei,Zhao Fengyu
Hexamethylenediamine (HMDA) is an important reagent for the synthesis of Nylon-6,6, and it is usually produced by the hydrogenation of adiponitrile using a toxic reagent of hydrocyanic acid. Herein, we developed an environmental friendly route to produce HMDA via catalytic reductive amination of 1,6-hexanediol (HDO) in the presence of hydrogen. The activities of several heterogeneous metal catalysts such as supported Ni, Co, Ru, Pt, Pd catalysts were screened for the present reaction in supercritical ammonia without any additives. Among the catalysts examined, Ru/Al 2 O 3 presented a high catalytic activity and highest selectivity for the desired product of HMDA. The high performance of Ru/Al 2 O 3 was discussed based on the Ru dispersion and the surface properties like the acid-basicity. In addition, the reaction parameters such as reaction temperature, time, H 2 and NH 3 pressure were examined, and the reaction processes were discussed in detail.
研究领域:
化学工程
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2017
·
IF 3.648
Junwei Zhang,Shuai Yang,Hang Li,Pengpeng Yu,Li Xu,Guoji Liu
The solubility of 1,6-Hexanediol in (methanol + dimethyl adipate (DMA)), ( n -butanol + DMA) binary solvents was measured by the dynamic method under 0.1 MPa. The studies were carried out at different mass fractions of methanol or n -butanol from 283.15 K to 303.15 K. The solubility of 1,6-Hexanediol in binary solvents increases with increasing temperature and mass fraction of methanol or n -butanol. In a fixed temperature and fixed mass fraction of methanol or n -butanol, the solubility of 1,6-Hexanediol in (methanol + DMA) is greater than in ( n -butanol + DMA). In addition, the experimental solubility data were correlated by Jouyban–Acree model, Van't Hoff–Jouyban–Acree model, modified Apelblat–Jouyban–Acree model and Sun model, in which the Sun model shows the best agreement with the experimental solubility data. The maximum of relative average deviation ( RAD ) and the root-mean-square deviation ( RMSD ) between the experimental and calculated solubility were 5.85 × 10 − 2 and 3.80 × 10 − 2 , respectively. Additionally, the thermodynamic properties (including enthalpy, Gibbs energy and entropy) were also obtained, and the results show that the dissolution of 1,6-Hexanediol in the two binary solvents is an endothermic process.
研究领域:
物理化学
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热力学
✓ 已验证
产品关联
DOI
高影响因子
Nano Research
·
2023
·Vol. 16
·期 10
·12270-12280
·
IF 9.9
Jiang Fengyang,Lan Tian,Sun Jiaqiang,Zhao Guofeng,Lu Yong
The gas-phase dehydrogenation of 1,6-hexanediol (1,6-HDO) to ε-caprolactone (ε-CL) over the high-performance Cu-based catalysts is highly desirable, but with grand challenges, because the Cu nanoparticles (NPs) are easy to be sintered with the low Hüttig temperature (< 150 °C vs. > 250 °C of reaction temperature). Herein, we report a highly efficient silica-encapsulated nano-Cu catalyst (Cu@SiO 2 /SiO 2 ) prepared via a complexation-impregnation method for the dehydrogenation of 1,6-HDO, exhibiting a 1,6-HDO conversion of 95.3% and ε-CL selectivity of 80.0% at 270 °C. The catalyst also has the outstanding thermal stability (without sintering up to 270 °C for 100 h on stream), which can be attributed to the effective encapsulation of the SiO 2 shell. In addition, the reaction network of 1,6-HDO dehydrogenation is proved. Finally, the pyridine-diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and in-situ X-ray photoelectron spectroscopy (XPS) reveal that the Cu 0 species favor the conversion of 1,6-HDO to ε-CL. The synergistic effect of Cu + and Cu 0 benefits the conversion of ε-CL to 2-methylcyclopentanone (2-MCPN). This study is beneficial for designing the high-performance Cu-based catalysts for 1,6-HDO to ε-CL, understanding the reaction network of 1,6-HDO dehydrogenation over the Cu-based catalysts, and offering a strong foundation for the large-scale production of ε-CL.
研究领域:
化学工程
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材料科学
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催化反应
✓ 已验证
产品关联
DOI
高影响因子
POLYMER
·
2025
·
IF 4.5
Wanjing Zhang,Liyan Wang,Yunsheng Chong,Wei Liu,Xin Qian
In this study, the copolyester plasticizers PHNAZ, synthesized from azelaic acid and hexanediol and modified by neopentyl glycol (NPG), was prepared via direct esterification. A series of characterization tests revealed that the number-average molecular weight of the PHNAZ copolyester plasticizers was less than 2000 with a dispersion coefficient of less than 2, demonstrating excellent thermal stability below 250 °C. PVC samples plasticized with PHNAZ showed thermal degradation temperatures above 250 °C, reduced glass transition temperatures to −33 °C, and significantly improved hydrophilicity. Notably, the water contact angle of PHNAZ-50/PVC was smallest, averaging 53.956°. The highlight of the study is the cytotoxicity testing of the prepared PHNAZ copolyester plasticizer at concentrations of 1 μg/mL, 10 μg/mL, and 50 μg/mL, where the average cell survival rate exceeded 100 %, indicating excellent biocompatibility. Additionally, PHNAZ displayed outstanding plasticizing effects, particularly PHNAZ-20/PVC, which achieved an elongation at break of 913.6 % and a plasticizing efficiency of 260.0 %. These results suggest that PHNAZ not only excels in chemical and thermal properties but also exhibits good biocompatibility and high plasticizing capability, indicating broad application prospects.
研究领域:
材料科学
·
生物学
✓ 已验证
产品关联
DOI
高影响因子
CATALYSIS TODAY
·
2024
·
IF 5.2
Zhe-Hui Zhang,Ming-Jie Song,Saravanakumar Elangovan,Zhuohua Sun,Tong-Qi Yuan
Lignin is the largest renewable source of aromatic building blocks in nature and has great potential as a starting material for the production of bulk or functionalized aromatic compounds, providing a suitable alternative to widely used petroleum-derived chemicals. In this work, we present a novel 1,4-cyclohexanediol (CHDO) preparation from lignocellulose. In contrast to conventional methods, this pathway has taken the lignin-degrading monomers as a starting point, and flexibly employs a series of oxidative and catalytic reactions to achieve the preparation of CHDO. The proposed pathway consists of a two-step chemical process to efficiently obtain high yields of CHDO from lignocellulose. The first step is the oxidation of lignin-derived monophenols to p -hydroxyl phenolic compounds using the Dakin oxidation reaction (yield>80%), and finally the de-functionalization and hydrogenation of the resulting monomers using the hydrodeoxygenation (HDO) reaction.
研究领域:
化学工程
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有机化学
·
可再生能源
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POLYMERS AND THE ENVIRONMENT
·
2022
·Vol. 31
·期 3
·1144-1159
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IF 4.705
Siegu William Mawuko Kodzo,Djouonkep Lesly Dasilva Wandji,Selabi Naomie Beolle Songwe,Bonku Emmanuel Mintah,Cheng Zhengzai,Gauthier Mario
The rising cost of petrochemicals owing to the rapid depletion of fossil resources has gradually divert research interest to novel chemicals derived from biomass feedstock. In this study we explored the synthesis, properties and ecotoxicity of a series of sustainable poly(hexylene 2,5-thiophenedicarboxylate- co -bis(2-hydroxyethoxybenzene)s (PTBHs) copolyesters suitable as form-fil-seal packaging materials. From the results, simply varying the ratios of HDO/BHEB afford control over the copolymers crystallinity, thermal and mechanical properties including degradability. The thermal analysis revealed the copolyesters possess satisfactory glass transition temperature (T g ) ranging from 75 to 112 °C and melting point from 160 to 205 °C, which are comparable to poly(ethylene furanoate) PEF and superior to poly(ethylene terephthalate) PET. These novel biopolymers exhibit tensile strength between 53 and 72 MPa and elongation at break of over 780%, higher than their corresponding homopolyesters. These promising properties were optimized with the increase of TH content, ranging from TB-enriched to TH-enriched copolyesters, exhibiting satisfactory heat-seal strength in the range of 0.77–0.45 N/mm. The biopolymers exhibit the potential as mere replacements to PETs, but their cost-rentability still needs to be investigated. Graphical Abstract The authors synthesized a novel class of fully non-toxic thiophene biopolymers and showed the synergistic effect of HDO on the structure, thermal and mechanical properties.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2024
·Vol. 14
·期 33
·23662-23671
·
IF 3.9
Wanjing Zhang,Liyan Wang,Hong Chen,Liying Guo,Yaoyao Bai,Xin Qian
A series of 2-methyl-1,3-propanediol (MPO) modified azelaic acid and hexylene glycol copolyester (PHMAZ) plasticizers with varying contents were synthesized using a direct esterification melt polycondensation method, and their structures were characterized systematically. Analysis using infrared spectroscopy and nuclear magnetic resonance spectroscopy confirmed the synthesis of the designed copolyester structure. Gel permeation chromatography (GPC) tests indicated that the number average molecular weight of each copolyester sample ranged between 2000 and 3000. These copolyesters were used to plasticize polyvinyl chloride (PVC) resin, and the glass transition temperature of the plasticized PVC samples was tested using a differential scanning calorimeter (DSC). Further characterization of the plasticizing effects was conducted using an electronic universal testing machine. The research results showed that as the content of MPO increased, the plasticizing effect of the copolyester initially increased and then decreased. Specifically, the copolyester containing 45% MPO, PHMAZ-45, demonstrated the best plasticizing effect on PVC, with the glass transition temperature of the plasticized PVC system around −35 °C, elongation at break at 908.4%, and a plasticizing efficiency of 254.5%. Additionally, this new type of copolyester plasticizer uses bio-based raw materials, exhibits excellent plasticizing effects, and the preparation process is stable and controllable. It holds promising potential to replace traditional volatile and toxic phthalate esters, presenting significant industrial application value.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
·
2020
·
IF 2.888
Xingchuan Yang,Xiangmeng Chen,Chunmei Cao,Li Xu,Guoji Liu
Solubility and liquid–liquid equilibria data for ternary systems for (water + 1,6-hexanediol + 1-butanol/2-methyl-1-propanol) were obtained at (293.15–323.15) K under atmospheric pressure. The LLE data were determined using a double-jacketed glass vessel, and the solubility curves were acquired by the cloud-point method. The distribution coefficient and separation factors were calculated and the reliability of experimental data was assessed by the Othmer–Tobias equation and Hand equation. The measured LLE data were fitted by NRTL and UNIQUAC models and binary parameters were obtained by using of Aspen Plus software. The calculated root-mean-square deviation values show that the calculated results from models showed good agreement with experimental data.
研究领域:
化学工程
·
热力学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
·
2020
·
IF 2.888
Xingchuan Yang,Huanxin Li,Chunmei Cao,Li Xu,Guoji Liu
Liquid-liquid equilibria (LLE) data for ternary systems of water + 1,6-hexanediol + 1-pentanol/ 3-methyl-1-butanol/ 2-methyl-2-butanol were measured at (293.15, 303.15, 313.15 and 323.15) K under 101.3 kPa. Cloud-point method was applied to determine the solubility curves data. Distribution coefficient and separation factors for 1,6-hexanediol were calculated from the measured tie-line data to evaluate the extraction effect of alcohols on 1,6-hexanediol. The reliability of experimental LLE data were tested by Othmer–Tobias equation and Hand equation, NRTL and UNIQUAC models were applied to correlate the measured data and the calculated results show that both models can fit the experimental data very well.
研究领域:
化学工程
·
热力学
✓ 已验证
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2019
·
IF 2.298
Xingchuan Yang,Huanxin Li,Chunmei Cao,Zongpeng Zou,Li Xu,Guoji Liu
Saturated vapor pressures of pure dimethyl adipate and isobaric vapor–liquid equilibrium (VLE) data for the binary system of dimethyl adipate + 1,6-hexanediol at 10, 20, and 99 kPa were determined by a modified Othmer still. All of the VLE data passed the thermodynamic consistency test by Wisniak and Van Ness methods. The experimental data were correlated with the NRTL, Wilson, and UNIQUAC models. The results showed that the UNIQUAC model is slightly better among the three models.
研究领域:
化学工程
·
热力学
✓ 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）