INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2020
·
IF 3.573
Shanshan Shao,Xianliang Xiang,Xiaohua Li,Huiyan Zhang,Rui Xiao,Yixi Cai
Acetic acid, n-butyraldehyde, furfural, n-butanol, and ethyl acetate as model compounds of biomass pyrolysis vapors were selected as reactants for ketonization over CeO2. Catalytic conversion of single components was conducted to understand their ketonization characteristics and also to obtain the overlapped temperature range. The results showed that the yield of acetone from directional ketonization of acetic acid reached a maximum of 97.4% at 360 °C over CeO2 with numerous oxygen vacancies, while n-butyraldehyde, n-butanol, and ethyl acetate performed the best at 420 °C with limited yield of ketones of 47.2, 35.1, and 85.4%, respectively. At the overlapped 420 °C, owing to the dehydration of acetic acid molecules, the ketonization of n-butyraldehyde was promoted with the largest overall yield of ketones of 96.5%. A mixture of furfural/acetic acid (1:4) brought about a lower yield of ketones of 78.8%, indicating a negative synergism due to active sites occupation by furfural adsorption.
✓ 已验证
产品关联
DOI
高影响因子
ENERGY
·
2020
·
IF 6.082
Hongwei Li,Zhigang Tang,Zhimin He,Xia Gui,Longpeng Cui,Xian-zhong Mao
In order to show the structure-activity relationship for CO 2 absorbent, and identify or screen novel and efficient physical solvents of CO 2 , the constant-volume method, the Peng-Robinson equation of state , and a molecular simulation were used to investigate the impacts of type of functional groups, carbon chain length and number of functional groups for nine physical solvents. The three methods produced highly consistent results. Comparison of the CO 2 solubility in solvents with the same carbon numbers but different functional groups suggested that the ester group could promote CO 2 absorption. Investigation of the CO 2 solubility in solvents with one ester group but different carbon chain lengths revealed that longer carbon chains could enhance CO 2 absorption. Analyses of the CO 2 solubility of solvents with one and two ester groups demonstrated that more ester groups could further increase the CO 2 absorption. Therefore, the presence and number of ester groups and increased carbon chain length could promote CO 2 absorption. It provides direction and method for screening of highly efficient CO 2 absorbents and for the design and synthesis of new solvents.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2020
·
IF 5.065
Yajun Li,Junjia Chen,Kui Wu
The knowledge of solid-liquid equilibrium data and solution thermodynamics of 2,2,2-trichloroacetamide (TCAcAm) in different solvents are essential for its synthesis, purification and further theoretical studies. In this paper, the solubility of TCAcAm in fifteen mono solvents of methanol, ethanol, n -propanol, isopropanol, n -butanol, isobutanol , n -pentanol, isopentanol, 2-butanone, acetone, ethyl acetate , 2-pentanone, acetonitrile , methyl acetate and ethyl formate was obtained through a gravimetric method at the temperature from 272.15 to 324.15 K under ambient pressure. The mole fraction solubility of TCAcAm in mono solvents showed an increasing trend with increasing temperature, and the phase equilibrium data in ketones and esters was much larger than that in alcohols. The experimental solubility can be well correlated using several thermodynamic models, such as the modified Apelblat equation, λh equation, non-random two-liquid (NRTL) model and the Wilson model. The obtained maximum relative average deviation ( RAD ) and root-mean-square deviation ( RMSD ) were 6.02 × 10 −3 and 2.086 × 10 −3 respectively. Besides, the dissolution enthalpy, entropy, and Gibbs free energy were calculated on the basis of thermodynamic relations and the Wilson model, which revealed that the dissolution of TCAcAm was a spontaneous and endothermic process.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2020
·
IF 5.065
Kui Wu,Yajun Li
The synthesis and separation processes of chemical intermediate is based on the knowledge of its solid-liquid phase equilibrium with solvents in industry. In this work, the solubility of 2-chlorobenzenesulfonamide in 16 single pure solvents including methanol, ethanol, n -propanol, isopropanol, n -butanol, isobutanol , acetone, 2-butanone, 2-pentanone, cyclohexanone , cyclopentanone , ethyl acetate , methyl acetate , ethyl formate , acetonitrile and tetrahydrofuran was determined at temperature range from 273.15 to 324.65 K and atmospheric pressure. The mole fraction solubility of 2-chlorobenzenesulfonamide in all selected mono solvents was enhanced by an increase in temperature. In addition, the experimental data were further correlated by the modified Apelblat equation, λh equation, NRTL model and Wilson model. The values of RAD with NRTL equation were smaller than those with other three models, and thus the NRTL model offered the best fitting performance. The thermodynamic functions of dissolution including enthalpy, entropy, and Gibbs energy were derived, and the results expectedly suggested a spontaneous and entropy-driven mixing process. All the crystallographic and thermodynamic data reported in this study provides the fundamental data for designing and optimizing of the reaction and crystallization processes of 2-chlorobenzenesulfonamide.
✓ 已验证
产品关联
DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2020
·
IF 3.594
Xiaomin Shuai,Zhiqiang Cai,Yujie Chen,Xinyu Zhao,Qianqian Song,Kaixin Ren,Xingxing Jiang,Tao Sun,Shaoqiang Hu
Here we report the first example of employing p- nitro-octadecyloxy-calix[8]arene (C8A-NO 2 ) as stationary phase for capillary gas chromatographic (GC) separations. The statically coated C8A-NO 2 column provided column efficiencies of 2554 plates/m and showed moderate polarity. Its selectivity and retention behaviour were investigated by a number of mixtures of diverse analytes and their isomers. It was found that the C8A-NO 2 column exhibited high resolving capability for aliphatic and aromatic analytes from apolar to polar nature, especially for positional and structural isomers. Among them, advantageous resolving capability over the commercial polysiloxane DB-1701 and DB-17 columns was obtained for chloroaniline and bromoaniline isomers. In addition, the C8A-NO 2 column was applied for the determination of isomer impurities in commercial reagents of geraniol, cis -decahydronaphthalene, and trans -decahydronaphthalene.
✓ 已验证
产品关联
DOI
高影响因子
RENEWABLE ENERGY
·
2021
·
IF 8.001
Shanshan Shao,Chengyue Liu,Xianliang Xiang,Xiaohua Li,Huiyan Zhang,Rui Xiao,Yixi Cai
Catalytic conversion of pyrolysis vapor from biomass was performed over CeO 2 catalysts to produce ketones. Thermogravimetric-gas chromatography/mass spectrometry (TG-GC/MS) and TG-MS were applied to understand the distribution of pyrolysis vapors from various biomass including rape straw, poplar, cypress and bagasse. The favorable biomass feedstock with high yield of ketones and other useful components were screened out for directional ketonization. The results showed that the temperature range of biomass pyrolysis was generally below 400 °C, and bagasse was a reasonable raw material for ketonization with the highest yield of ketones of 33.68% at 380 °C, since it contained the most cellulose and hemicellulose in biomass of the same quality. The activity of acetone increased at higher temperature, and secondary reaction occurred, resulting in a reduction in the overall yield of ketones. The total yield of ketones from bagasse treated for 9 h was boosted by 16.18% higher than that from nonseawater-treated biomass. By the introduction of metal ions effectively, the component of the pyrolysis vapor changed, making it easier for large molecular substances to be converted to small ones during pyrolysis. Through this research, the effective utilization of biomass could be realized.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2019
·
IF 3.858
Tiantian Shi,Meiling Qi,Xuebin Huang
Developing highly selective stationary phases is essential to address the issues for separation of analytes with similar properties and various components in complex samples. Herein, we report a new triptycene-based material functionalized with polycaprolactone moieties (TP-PCL) as the stationary phase with high-resolution performance for gas chromatography (GC). The TP-PCL capillary column exhibited column efficiency of 5555 plates/m and moderate polarity. On the column, dozens of mixtures of positional and structural isomers can be well resolved, involving benzene derivatives with varying substituents (alkyl, halo, nitro, hydroxyl, amino), naphthalene derivatives, alkanes and alcohols. It exhibits advantageous performance for high resolution of the critical pairs of alkylbenzenes, phenols, anilines and alkanes over the PCL column and commercial DB-35 MS column with similar polarity. Moreover, the TP-PCL column showed excellent separation repeatability and reproducibility with RSD values of 0.02%−0.07% for run-to-run ( n = 4), 0.11%−0.18% for day-to-day ( n = 4) and 2.1%−4.7% for column-to-column ( n = 4). In addition, it exhibited distinctly enhanced thermal stability in contrast to the PCL column. Its application to analysis of the essential oil from Artemisiae argyi proves its good potential for practical use.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ORGANIC CHEMISTRY
·
2019
·
IF 4.745
Fei-Fei Chen,Yu-Hui Zhang,Zhi-Jun Zhang,Lei Liu,Jian-Ping Wu,Jian-He Xu,Gao-Wei Zheng
(R)-Amination mediated by (R)-specific ω-transaminases generally requires costly d-alanine in excess to obtain the desired chiral amines in high yield. Herein, a one-pot, trienzymatic cascade comprising an (R)-specific ω-transaminase, an amine dehydrogenase, and a formate dehydrogenase was developed for the economical and eco-friendly synthesis of (R)-chiral amines. Using inexpensive ammonium formate as the sole sacrificial agent, the established cascade system enabled efficient ω-transaminase-mediated (R)-amination of various ketones, with high conversions and excellent ee (>99%); water and CO2 were the only waste products.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ELECTROPHORESIS
·
2019
·
IF 2.754
Yuan-Yuan Cui,Huan Yao,Cheng-Xiong Yang,Xiu-Ping Yan
Microporous organic networks (MONs) are a new class of porous materials synthesized via Sonogashira coupling reactions between organic building blocks. Here we report an in situ synthesis approach to fabricate MONs coated capillary column for high resolution GC separation of hydrocarbons. The McReynolds constant evaluation reveals the MONs coated capillary is a non-polar column. The MONs coated capillary column shows good resolution for GC separation of diverse important industrial hydrocarbons such as linear and branched alkanes, alkylbenzenes, pinene isomers, ethylbenzene and styrene, cyclohexane and benzene. The MONs coated capillary column gave a high column efficiency of 1542 plates per meter for hexane and good precision for replicate separations of the selected hydrocarbons with the RSDs of 0.2–0.3, 1.5–3.1, and 1.9–3.3% for retention time, peak height and peak area, respectively. The MONs coated capillary also offered better resolution than commercial Inert Cap-1 and Inert Cap-5 capillary columns for hexane and heptane isomers. These results reveal the potential of MONs as novel stationary phases in GC.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2019
·
IF 3.858
Zi-Meng Wang,Cheng-Xiong Yang,Xiu-Ping Yan
Chiral crystalline sponges (CCSs) are a recent class of chiral porous metal complexes potential in chiral recognition. Here we report the fabrication of polysiloxane OV-1701 incorporated CCS-3S (PSO/CCS-3S) coated capillary column as a novel stationary phase for gas chromatographic separation of diverse racemates. CCS-3S with the chiral ligand of ( S )-mandelic was selected as the model CCS. With the aid of polysiloxane OV-1701, PSO/CCS-3S coated capillary column gave improved resolution, broader enantiomers separation scope and much larger McReynolds constants than CCS-3S coated capillary column. Many racemates that cannot be separated on CCS-3S coated capillary column were well resolved on PSO/CCS-3S coated capillary column. The PSO/CCS-3S coated capillary column also gave wide linear range, low limit of detection, good repeatability and reproducibility, and fine inertness and anti-column bleeding properties for the separation of enantiomers. In addition, the PSO/CCS-3S coated capillary column presented better resolution for the studied racemates than commercial β-cyclodextrin based Cyclosil B (30 m long ×0.32 mm i.d. × 0.25 μm film thickness), β-DEX 225 (30 m long ×0.25 mm i.d. × 0.25 μm film thickness) and amino acid based Chirasil L-Val (25 m long ×0.25 mm i.d. × 0.12 μm film thickness) capillary columns. These results indicate the great potential of PSO/CCS-3S coated capillary column in separation of enantiomers.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2019
·
IF 5.399
Hui Shen,Mingquan Huang,Mouming Zhao,Weizheng Sun
Typical ketone flavours (with variations in chain length, position and number of keto group, branched chain) were selected to investigate the effect of molecule structure of ketones on their interactions with myofibrillar proteins (MPs). Results showed that 2,3-pentanedione quenched the fluorescence of MPs more effectively than 2-pentanone and 3-pentanone due to the number of keto group. There was no significant difference between 5-methyl-2-hexanone and 2-heptanone, which was attributed to their similar molecular size and polarity. The quenching effect of homologous ketone flavours increased with carbon chain growth due to the higher hydrophobic interaction. Dynamic quenching played a major role in the fluorescence quenching process of MPs by 2-pentanone, 3-pentanone, 5-methyl-2-hexanone, 2-heptanone and 2-octanone. The α-helix content decreased gradually with the increase of ketones concentration. Results of GC/MS were in accordance with the fluorescence quenching analysis generally, whereas 2,3-pentanedione and 2-nonanone exhibited some differences due to their higher steric hindrance effects.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2019
·
IF 4.561
Yajun Li,Kui Wu,Lei Liang
The solid-liquid equilibrium solubility of 2-phenylacetamide in sixteen pure solvents, i.e. methanol, ethanol, n -propanol, isopropanol, n -butanol, isobutanol , n -pentanol, isopentanol, acetone, ethyl acetate , acetonitrile , 2-butanone, 2-pentanone, methyl acetate , ethyl formate and tetrahydrofuran was obtained over a temperature range from 273.75 K to 324.95 K by a gravimetric method under atmospheric pressure. For all the solvents investigated, the equilibrium solubility of 2-phenylacetamide increases with augmented temperature. The statistical correlations were correlated by the modified Apelblat model, λh equation, non-random two-liquid (NRTL) equation and the Wilson equation. On the basis of thermodynamic relations and the Wilson model, the dissolution enthalpy, entropy, and Gibbs free energy were calculated. The results demonstrate that the dissolution of 2-phenylacetamide is a spontaneous and entropy-driven process in the selected solvents. The solubility data, correlation models and derived dissolution properties would promote the development of the separation and reaction of 2-phenylacetamide in industry.
✓ 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）