Analytical Methods
·
2021
·Vol. 13
·期 26
·2989-2996
·
IF 2.896
Yiwen Cao,Shenjie Zhu,Lin Zhang,Qun Cui,Haiyan Wang
Aiming at the difficulty in qualitative and quantitative analysis of trace compositions in food preservative propionic acid, the trace compositions and the key components influencing the total aldehyde content in propionic acid were analyzed by gas chromatography-mass spectrometry (GC-MS), high performance liquid chromatography (HPLC) and gas chromatography (GC) in this paper. The results show that the food preservative propionic acid contains 18 trace compositions. The main compositions affecting the total aldehyde content in propionic acid are acetaldehyde, propionaldehyde, 1-cyclopropyl-1-propanone and 2-methyl-2-pentenal, which account for ∼90% of the total aldehyde content in propionic acid. The total aldehyde content in propionic acid can be quickly determined by iodometric titration. However, the impurity compositions, solution oxygen content and pH value of propionic acid may affect the stability of NaHSO3, which lead to a higher titration value of the aldehyde content. The total aldehyde contents in propionic acid determined by GC (148.535–337.890 mg L−1) and HPLC (157.730–335.780 mg L−1) are close and reliable with a relative deviation of 0.31–3.00%. The volatile low-carbon aldehydes and ketones including formaldehyde, acetaldehyde and acetone have a weak response and a high detection limit in GC. The derivation conditions of all aldehydes and ketones in propionic acid should affect the determination results of HPLC. It provides the basic data for quality improvement and ultra-deep purification of food-grade propionic acid.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2020
·Vol. 10
·期 31
·18192-18199
·
IF 3.119
Zihao Yang,Taiheng Yin,Fengfan Zhang,Wei Wu,Meiqin Lin,Zhaoxia Dong,Juan Zhang
To study the microscopic dispersion state of CO2 in different ester solvents, the solubility, volume expansion coefficients and in situ Fourier transform infrared (FTIR) spectra of the CO2–ester system were measured. The results show that the solubility and expansion coefficient of CO2 in ester solvents decreases as the hydrocarbon chain increases. As the pressure increases, the infrared absorption peaks of CO2 and the functional groups characteristic of ester molecules shift, indicating that CO2 molecules interact with ester molecules and that CO2 would destroy the interactions between the ester molecules. The hydrocarbon chain length of the ester molecules has a significant effect on the infrared absorption peak of the CO2–ester system. As the hydrocarbon chain length increases, the CO2 absorption peak shift and peak shift of the carbonyl groups in the ester gradually decrease.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ELECTROCHIMICA ACTA
·
2026
·
IF 5.8
Yifan Wu,Changquan Wu,Sisi Xiong,Shangquan Zhao,Naigen Zhou,Xuerui Yang
DFT, AIMD, and classical MD simulations reveal that α-H activity and LUMO level is key factor in carboxylate reduction stability. • Propionate electrolytes exhibit narrower interfacial functional regions and enhanced protection. • Theoretical predictions are rigorously validated by experimental Li||NCM9055 full-cell cycling tests. Carboxylate solvents are essential for high-energy-density lithium metal batteries (LMBs) due to their low viscosity and superior low-temperature performance, yet conventional methyl acetate (MA) and ethyl acetate (EA) exhibit poor cycling stability caused by their inherent reduction instability. While a wide library of carboxylate derivatives exists with varying functional groups and chain lengths, their systematic structure-performance relationships remain elusive. In this work, we present an atomic-level investigation into 12 carboxylate solvents and their corresponding “single-salt–single-solvent” (4S) electrolytes using a combination of DFT, AIMD, and classical MD simulations. Our results reveal that the failure of MA- and EA-based systems stems from high α -H reactivity and unfavorable interfacial solvation structures, whereas propyl propionate (PP) and butyl propionate (BP) offer significantly enhanced reduction resistance and robust electrode-electrolyte interfaces. These computational predictions are in excellent agreement with experimental Li||NCM9055 full-cell cycling tests. This study elucidates the cyclic decay mechanism of short-chain esters and provides a theoretical foundation for the future design of high-performance carboxylate-based electrolytes for next-generation LMBs. Download: Download high-res image (277KB) Download: Download full-size image
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2023
·
IF 4.7
Mingxia Yang,Senqing Fan,Jiaojiao Chen,Yu Chen,Chuang Li,Jiaxin Meng,Haijie Qing,Yangchao Liu,Zeyi Xiao
An electrocatalytic membrane structured reactor (EMSR) fabricated by loading MnO 2 catalyst in Ti membrane pores for oxidation of n-propanol coupled with hydrogen evolution. During the process of n-propanol oxidation coupled with hydrogen evolution by MnO 2 @Ti EMSR via flow-through mode, the conversion rate of n-propanol was increased by 44%, the selectivity of propionic acid was increased by 33%, and the Faraday efficiency was increased by 59%, compared with those of MnO 2 /Ti membrane with MnO 2 immobilized on the membrane surface. Enhanced contact and mass transfer are two contributors for the catalytic performance improvement by MnO 2 @Ti EMSR via flow-through mode. Besides, the cell voltage during n-propanol oxidation coupled with hydrogen production is decreased by 305 mV with energy consumption reduced by 0.73 kWh Nm H2 -3 , compared with those of hydrogen evolution by water splitting with oxygen evolution reaction. The achievements of this work provide a promising strategy for coproduction of propionic acid and hydrogen.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2009
·
IF 2.063
Li Hongling,Zhu Rongjiao,Xu Wei,Xu Hongfei,Dong Zeliang,Tian Yiling
High-pressure vapor−liquid equilibrium data for (methyl propionate + carbon dioxide) and (propyl propionate (PP) + carbon dioxide) were measured at pressures from (1.00 to 12.00) MPa and temperatures in the range from (313.0 to 373.0) K. Experimental results were correlated with the Peng−Robinson equation of state with the two-parameter van der Waals mixing rule. At the same time, the Henry’s coefficient and partial molar enthalpy change and partial molar entropy change of CO2 during dissolution at different temperature were also calculated.
✓ 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）