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    Efficiency of fluorinated alcohol for extraction of organic acid from its dilute aqueous solution: A model study
    (Elsevier Science Sa, 2015) Luo, Yuhong; Chang, Zhidong; Wu, Xue; Uslu, Hasan; Li, Wenjun; Hua, Chao; Liu, Shixiang
    1H,1H,2H,2H-Perfluoro-1-octanol, octanol and benzoic acid were selected as model extractant and target acid to investigate extraction behaviors of fluorinated n-alcohol. According to experimental results, the extraction capacity of 1H,1H,2H,2H-perfluoro-1-octanol is acceptable with distribution ratio (D) of 13. The extraction efficiency reaches 98.0% after three stage continuous countercurrent extraction under the conditions of pH 2.55-3.16 and temperature 20-25 degrees C at oil to water (V-o/V-w) ratio of 1. The residual of 1H,1H,2H,2H-perfluoro-1-octanol in aqueous phase was quite low, which was less than 2 ppm. The back-extraction of 1H,1H,2H,2H-perfluoro-1-octanol by NaOH was demonstrated to be feasible, which is up to 100% with single stage. (C) 2015 Elsevier B.V. All rights reserved.
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    Efficiency of fluorinated alcohol for extraction of organic acid from its dilute aqueous solution: A molecular optimization study of extractant
    (Elsevier Science Sa, 2015) Luo, Yuhong; Chang, Zhidong; Blamo, Benjemin John; Wu, Xue; Hussain, Muhammad; Uslu, Hasan; Li, Wenjun
    The quantum chemical parameters of fluorinated octanol, such as charge distribution, molecular electrostatic potential and frontier molecular orbital have been investigated through quantum chemistry calculation by DFT method using the B3LYP level with the standard 6-311++G(d,p) basis set. In first step the natural population analysis (NPA) and molecular electrostatic potential (MEP) methods were applied to determine the reactive site of fluorinated octanol. In second step comparative analysis of frontier molecular orbital energy gaps of fluorinated octanol and benzoic acid was used to investigate the effect of fluorinated substitutional degree on benzoic acid extraction behavior of fluorinated octanol. The calculated results suggested that the reactive site is localized on the oxygen atom and the electron donor strength of the oxygen atom decreases with the increase of the fluorinated substitional degree due to the electron-withdrawing of fluorous group. 1H,1H,2H,2H-perfluoro-1-octanol and 5,5,6,6,7,7, 8,8-nonafluoro-1-octanol were selected as the extractants to testify the proposed theory. According to the prediction, the extraction capability on benzoic acid by 1H,1H,2H,2H-perfluoro-1-octanol is lower than that of 5,5,6,6,7,7,8,8-nonafluoro-1-octanol at room temperature. The experimental results are in agreement with the corresponding theoretical data. (C) 2015 Elsevier B.V. All rights reserved.