SEPARATION AND PURIFICATION TECHNOLOGY
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2017
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IF 3.359
Ying Zhang,Ting-An Zhang,David Dreisinger,Weihua Zhou,Feng Xie,Guozhi Lv,Weiguang Zhang
In the current study, a novel chelating extractant Mextral 973H was employed to selectively extract V(V) from a low pH sulfuric acid solution containing high concentration of Fe (Ш). The extraction of V(V) is strongly dependent on solution pH, and the separation coefficient (β (V/Fe) ) between V(V) and Fe(Ш) can be greater than 720 when the solution pH < 0.5. A cation exchange between H and VO 2 + was proposed as the main extraction mechanism at pH < 1.5, while at pH > 1.5, a solvating reaction between the extractant and metal-oxo cluster anions took place. The effects of solution pH, acid medium types, contacting time and temperatures on the extraction and separation of V have been discussed. FT-IR and 1 HNMR were applied to confirm the extraction mechanism and also the degradation behavior of Mextral 973H in some extreme conditions. The loaded vanadium was effectively stripped using a diluted 0.2 M Na 2 CO 3 solution and a total stripping extent of 97% was achieved. The extraction process by Mextral 973H was finally simulated using Aspen Plus simulator comparing to traditional process, the results obtained were in good recovery efficiency and with the advantage of acid and alkali saving.
研究领域:
化学工程
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环境科学
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DOI
高影响因子
JOURNAL OF FOOD SCIENCE AND TECHNOLOGY-MYSORE
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2019
·Vol. 56
·期 5
·2355-2364
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IF 1.85
Manzoor Muhammad Faisal,Zeng Xin-An,Rahaman Abdul,Siddeeg Azhari,Aadil Rana Muhammad,Ahmed Zahoor,Li Jian,Niu Debao
The aim of this paper is to investigate the combined impact of pulsed electric field (PEF) and ultrasound (US) to evaluate the physicochemical, bioactive compounds and chemical structure of almond extract. Almond extract was first treated with PEF and then with US. Combined treatment (PEF–US) has attained the highest value of total phenolics, total flavonoids, condense tannins, anthocyanin contents and antioxidant activity in DPPH, reducing power and metal chelating activity than all other treatments. Among all those treatments, there was slightly visible difference in the color. Moreover, FT-IR spectra indicate that the effect of PEF-US on almond extract did not produce new carbonyl compounds, but led to the higher concentration of these compounds. This study demonstrated that the PEF-US could be useful for the extraction of bioactive compounds as well as improving the stability of volatile compounds.
研究领域:
食品科学
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植物化学
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DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
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2017
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IF 3.648
Yaran Yin,Taotao Fu,Chunying Zhu,Youguang Ma
Densities and viscosities of binary mixtures {[Bmim][BF 4 ] + MDEA}, {MDEA + H 2 O} and ternary mixture {[Bmim][BF 4 ] + MDEA + H 2 O} were measured at T = (293.15–333.15) K. The volumetric and viscometric properties of binary and ternary mixtures, such as excess molar volume ( V E ), viscosity deviation (Δ η ), excess Gibbs energy of activation of viscous flow (Δ G ⁎E ), and Grunberg-Nissan interaction parameter ( G 12 ), were deduced from experimental data. The excess molar volumes and viscosities data were used to calculate the Redlich-Kister and Jouyban-Acree equations coefficients for binary mixtures , and Singh et al. and Jouyban-Acree extended equations coefficients for ternary mixtures. The intermolecular interactions in binary and ternary mixtures were discussed through volumetric and viscometric properties and FT-IR spectroscopic analysis .
研究领域:
物理化学
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材料科学
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2021
·
IF 7.312
Ruibing Bai,Junfeng Wang,Daoguang Wang,Yanqiang Zhang,Junjie Cui
The high acidity of stripping is one of the major problems that hinder the industrialization of the tributyl phosphate (TBP) + FeCl 3 system for lithium extraction from the salt lake brines with high Mg/Li ratio. In this study, a novel solvent extraction system, trialkylmethylammonium di(2-ethylhexyl)orthophosphinate ([N 1888 ][P 507 ]) + TBP + FeCl 3 , was developed to significantly reduce the difficulty of stripping and simplify the extraction process. The conditions of extraction and stripping were systematically studied in the present work. The results showed that Li + extraction efficiency could reach 61% under the optimal extraction parameters and Li + stripping ratio was 90% with a relative mild conditions of O/A = 10:1, [HCl] aq = 1.5 mol·L –1 . Also, combined with experimental results, FT-IR analysis, and UV analysis, the possible mechanisms of lithium extraction and stripping were put forward. Li + was extracted from the aqueous phase through the formation of [Li·2TBP][FeCl 4 ] adduct, meanwhile [N 1888 ][P 507 ] was just slightly involved in the extraction step. In the stripping procedure, the interaction between [FeCl 4 ] − and [Li·2TBP] + might be destroyed, and new possible complexes, [Li·2TBP] + , and [FeCl 4 ·TBP·P 507 ] 2− /[FeCl 4 ·P 507 ] 2− were formed in the organic phase. Additionally, the extraction efficiency of Li + remained above 70% while the organic phase was reused for six cycles. Compared with the traditional system, the addition of [N 1888 ][P 507 ] resulted in a slight decrease of Li + extraction efficiency (about 5%), the stripping acidity significantly reduced from 6 mol·L –1 HCl to 1.5 mol·L –1 HCl. This new extraction system showed a promising performance in selective extracting and easy stripping in lithium separation from the salt lake brines with high Mg/Li ratio.
研究领域:
化学工程
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材料科学
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环境化学
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无机化学
✓ 已验证
产品关联
DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2024
·
IF 4.9
Xu Liu,Peide An,Yide Han,Hao Meng,Xia Zhang
Cu-based nanozyme shows good oxidase-like activities due to the changeable states of Cu(II) and Cu(I), which are proven to be effective in the electron transfer in the redox process. Herein, the self-made MOF-818 with more Cu(II) loading was synthesized through a modified two-steps hydrothermal routes, which was then used as a sacrificial precursor to construct copper/zirconium composite oxides nanozymes (CN-MOF-818). The pyrolysis temperature was varied to obtain the best enzyme-like activities of the resulting CN-MOF-818. The laccase-like and catecholase-like activities were evaluated by using the oxidation of the mixture of 4-aminoantipyrine (4-AAP) and 2,4-dichlorophenol (2,4-DP), and 3,5-Di- tert -butylcatechol (3,5-DTBC) respectively. The enzyme-like activities were optimized through altering the catalytic conditions, and the corresponding enzyme catalytic kinetics including K m and V max were also determined. The enzyme-like mechanism of the CN-MOF-818 were also discussed based on EPR technique and the in-situ FT-IR analyses. In comparison with the pristine MOF-818 and the other reported Cu-based mimics, the as-prepared CN-MOF-818 exhibits the higher oxidase mimetic activities. These CN-MOF-818 can also be employed to detect the epinephrine with a low detection limit of 1.63 μM.
研究领域:
纳米技术
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催化
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分析化学
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生物化学
✓ 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）