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Stig Pedersenbjergaard - One of the best experts on this subject based on the ideXlab platform.

  • rapid determination of designer benzodiazepines benzodiazepines and z hypnotics in whole blood using parallel artificial liquid Membrane Extraction and uhplc ms ms
    Analytical and Bioanalytical Chemistry, 2018
    Co-Authors: Linda Vardal, Astrid Gjelstad, Stig Pedersenbjergaard, Gladys Wong, Ase Marit Leere Oiestad, Elisabeth Leere Oiestad
    Abstract:

    Benzodiazepines (BZD) and Z-hypnotics are frequently analyzed in forensic laboratories, and in 2012, the designer benzodiazepines (DBZD) emerged on the illegal drug scene. DBZD represent a particular challenge demanding new analytical methods. In this work, parallel artificial liquid Membrane Extraction (PALME) is used for sample preparation of DBZD, BZD, and Z-hypnotics in whole blood prior to UHPLC-MS/MS analysis. PALME of BZD, DBZD, and Z-hypnotics was performed from whole blood samples, and the analytes were extracted across a supported liquid Membrane (SLM) and into an acceptor solution of dimethyl sulfoxide and 200 mM formic acid (75:25, v/v). The method was validated according to EMA guidelines. The method was linear throughout the calibration range (R2 > 0.99). Intra- and inter-day accuracy and precision, as well as matrix effects, were within the guideline limit of ± 15%. LOD and LLOQ ranged from 0.10 to 5.0 ng mL−1 and 3.2 to 160 ng mL−1, respectively. Extraction recoveries were reproducible and above 52%. The method was specific, and the analytes were stable in the PALME extracts for 4 and 10 days at 10 and − 20 °C. No carry-over was observed within the calibration range. PALME and UHPLC-MS/MS for the determination of DBZD, BZD, and Z-hypnotics in whole blood are a green and low-cost alternative that provides high sample throughput (96-well format), extensive sample clean-up, good sensitivity, and high reproducibility. The presented method is also the first method incorporating analysis of DBZD, BZD, and Z-hypnotics in whole blood in one efficient analysis.

  • one step Extraction of polar drugs from plasma by parallel artificial liquid Membrane Extraction
    Journal of Chromatography B, 2017
    Co-Authors: Veronika Pilařova, Stig Pedersenbjergaard, Mumtaz Sultani, Kristine Skoglund Ask, Lucie Novakova, Astrid Gjelstad
    Abstract:

    Abstract The new microExtraction technique named parallel artificial liquid Membrane Extraction (PALME) was introduced as an alternative approach to liquid–liquid Extraction of charged analytes from aqueous samples. The concept is based on Extraction of analytes across a supported liquid Membrane sustained in the pores of a thin polymeric Membrane, a well-known Extraction principle also used in hollow fiber liquid-phase microExtraction (HF-LPME). However, the new PALME technique offers a more user-friendly setup in which the supported liquid Membrane is incorporated in a 96 well plate system. Thus, high-throughput is achievable, in addition to the green chemistry offered by using PALME. The consumption of organic solvent is minimized to 3–5 μL per sample. With a sample volume of 250 μL and acceptor solution volume of 50 μL, a maximal enrichment factor of five is achievable. Based on these parameters, a new method for Extraction of polar basic drugs was developed in the present work. The basic drugs hydralazine, ephedrine, metaraminol, salbutamol, and cimetidine were used as model analytes, and were extracted from alkalized human plasma into an aqueous solution via the supported liquid Membrane. The Extraction was promoted by a carrier dissolved in the Membrane, creating a temporary ion-pair complex between the hydrophilic drug and the carrier. As the model analytes were extracted directly into an aqueous solution, there was no need for evaporation of the extract before injection into LC–MS. Hence, the sample preparation is performed in one step. With optimized conditions, the Extraction recoveries were in the range 50–89% from human plasma after 45 min Extraction. The data from the method evaluation were satisfactory and in line with current guidelines, and revealed an Extraction method with substantial potential for high throughput bioanalysis of polar basic drugs.

  • parallel artificial liquid Membrane Extraction micro scale liquid liquid liquid Extraction in the 96 well format
    Bioanalysis, 2013
    Co-Authors: Astrid Gjelstad, Knut E Rasmussen, Marthe Petrine Parmer, Stig Pedersenbjergaard
    Abstract:

    Background: This paper reports development of a new approach towards analytical liquid–liquid–liquid Membrane Extraction termed parallel artificial liquid Membrane Extraction. A donor plate and acceptor plate create a sandwich, in which each sample (human plasma) and acceptor solution is separated by an artificial liquid Membrane. Parallel artificial liquid Membrane Extraction is a modification of hollow-fiber liquid-phase microExtraction, where the hollow fibers are replaced by flat Membranes in a 96-well plate format. Results: Four basic drugs (pethidine, nortriptyline, methadone and haloperidol) were extracted from human plasma in 30 min, followed by analysis with LC–MS/MS. Extraction recoveries for the model analytes were in the range of 34–74% from human plasma. LOQs were in the range of 0.01–0.35 ng/ml, linearity above 0.9955 for all drugs and with RSD values below 12%. Conclusion: Liquid–liquid–liquid Membrane Extraction was successfully performed in a slightly modified commercially available 96-we...

  • on chip electro Membrane Extraction with online ultraviolet and mass spectrometric detection
    Analytical Chemistry, 2011
    Co-Authors: Nickolaj Jacob Petersen, H Jensen, Steen Honore Hansen, Sunniva Taule Foss, Detlef Snakenborg, Christian Skonberg, Jorg Peter Kutter, Stig Pedersenbjergaard
    Abstract:

    Electro Membrane Extraction was demonstrated in a microfluidic device. The device was composed of a 25 μm thick porous polypropylene Membrane bonded between two poly(methyl methacrylate) (PMMA) substrates, each having 50 μm deep channel structures facing the Membrane. The supported liquid Membrane (SLM) consisted of 2-nitrophenyl octyl ether (NPOE) immobilized in the pores of the Membrane. The driving force for the Extraction was a 15 V direct current (DC) electrical potential applied across the SLM. Samples containing the basic drugs pethidine, nortriptyline, methadone, haloperidol, loperamide, and amitriptyline were used to characterize the system. Extraction recoveries were typically in the range of 65−86% for the different analytes when the device was operated with a sample flow of 2.0 μL/min and an acceptor flow of 1.0 μL/min. With the sample flow at 9.0 μL/min and the acceptor flow at 0.0 μL/min, enrichment factors exceeding 75 were obtained during 12 min of operation from a total sample volume of o...

  • kinetic electro Membrane Extraction under stagnant conditions fast isolation of drugs from untreated human plasma
    Journal of Chromatography A, 2010
    Co-Authors: Lars Erik Eng Eibak, Astrid Gjelstad, Stig Pedersenbjergaard, Knut E Rasmussen
    Abstract:

    Amitriptyline, citalopram, fluoxetine, and fluvoxamine were isolated by electro Membrane Extraction (EME) from 70microl of untreated plasma (pH 7.4), through a supported liquid Membrane (SLM) of 1-ethyl-2-nitrobenzene immobilized in the pores of a porous polypropylene hollow fiber, and into 30microl of 10mM HCOOH as acceptor solution inside the lumen of the hollow fiber. The driving force of the Extraction was a 9V potential sustained over the SLM with a common battery, with the positive electrode placed in the plasma sample and the negative electrode placed in the acceptor solution. Extractions were performed under totally stagnant conditions with a very simple device for 1min (kinetic regime), and subsequently the acceptor solution was analyzed directly by liquid chromatography-mass spectrometry (LC-MS). Recoveries were 12, 13, 22, and 17% for fluoxetine, amitriptyline, citalopram, and fluvoxamine, respectively. Sample clean-up was comparable to reversed-phase solid-phase Extraction (SPE), but EME required substantially less time than SPE. The time advantage of EME was further improved by parallel Extraction of three samples (for 1min) with the same 9V battery. EME from plasma combined with LC-MS provided limits of quantification (S/N=10) in the range 0.4-2.3ng/ml, linearity in the range 1-1000ng/ml with r(2)-values of 0.998-0.999, and repeatability in the range 3.2-8.9% RSD in the mid-therapeutic window (100ng/ml).

Kun Huang - One of the best experts on this subject based on the ideXlab platform.

  • wettability and spreading behavior of organic extractant and its effect on formation of gas bubble supported organic liquid Membrane for large phase ratio Extraction
    Chemical Engineering and Processing, 2019
    Co-Authors: Kun Huang, Kaiqiang Zhang, Xiaohong Wu, Zhenmin Zhao
    Abstract:

    Abstract Our previous works suggested a novel method by spreading and covering a layer of organic extractant on the surface of gas bubbles to perform gas bubble-supported organic liquid Membrane Extraction at large aqueous-to-organic phase ratios. However, details about wettability and spreading kinetic behavior of organic extractant within the annular gaps between the internal gas and the external oil needles in the injector was not clear, and so did its effect on formation of gas bubble-supported organic liquid Membrane. In present work, spreading of P507 organic extractant on surface of two kinds of typical solid substrates, glass and PVC, with different hydrophilic-hydrophobicity is investigated. It is found that the spreading empirical coefficient k is a simple mathematical function of three crucial operation parameters in the process of gas bubble-supported organic Membrane Extraction: P507 concentration, saponification degree of P507, and pre-loading amount of rare earths in the organic phase. A feasible mathematical model is suggested for theoretical prediction of the spreading rate. Calculation based on the new model is more convenient than de Gennes’s model. The present work provides a scientific foundation for the design of hydrophilic-hydrophobicity of the materials for making the internal gas and the external oil needles in the injector.

  • chemical reaction driven spreading of an organic extractant on the gas water interface insight into the controllable formation of a gas bubble supported organic extractant liquid Membrane
    Langmuir, 2019
    Co-Authors: Kun Huang
    Abstract:

    The Extraction and recovery of low-concentration valuable metals from various complex aqueous solutions or industrial waste waters have attracted extensive interests in recent years. In our previous works, we suggested a novel technique called bubbling organic liquid Membrane Extraction by spreading and covering an organic extractant with extremely small volume on the surface of gas bubbles to form a layer of the gas bubble-supported organic liquid Membrane for selective Extraction and enrichment of low-concentration targets from dilute aqueous solutions. It was found that for successfully performing the bubbling organic liquid Membrane Extraction, a prerequisite is knowing how to control the formation of a stable organic liquid Membrane covered on the surface of gas bubbles. However, once the organic extractant starts to spread on the surface of gas bubbles, the Extraction chemical reaction at the interface between the organic extractant liquid Membrane and the rare-earth aqueous solution will occur. In ...

  • chemical reaction driven spreading of an organic extractant on the gas water interface insight into the controllable formation of a gas bubble supported organic extractant liquid Membrane
    Langmuir, 2019
    Co-Authors: Jie Liu, Kun Huang, Wenqian Liu, Huizhou Liu
    Abstract:

    The Extraction and recovery of low-concentration valuable metals from various complex aqueous solutions or industrial waste waters have attracted extensive interests in recent years. In our previous works, we suggested a novel technique called bubbling organic liquid Membrane Extraction by spreading and covering an organic extractant with extremely small volume on the surface of gas bubbles to form a layer of the gas bubble-supported organic liquid Membrane for selective Extraction and enrichment of low-concentration targets from dilute aqueous solutions. It was found that for successfully performing the bubbling organic liquid Membrane Extraction, a prerequisite is knowing how to control the formation of a stable organic liquid Membrane covered on the surface of gas bubbles. However, once the organic extractant starts to spread on the surface of gas bubbles, the Extraction chemical reaction at the interface between the organic extractant liquid Membrane and the rare-earth aqueous solution will occur. In the present work, the spreading behavior of the organic extractant P507 on the surface of rare-earth aqueous solutions was investigated and was compared with the behaviors on the surface of deionized water. It was revealed that the spreading of the organic extractant P507 on the surface of aqueous solutions containing rare-earth ions was accelerated because of the occurrence of the chemical reactions at the gas-water interface. The difference in the spreading rate of organic extractant P507 liquid droplets on the surface of deionized water and on that of Er(III) aqueous solutions with an increase in the P507 concentration, the saponification degrees of the P507 extractant, and the preloading amount of Er(III) in the P507 extractant revealed that the chemical reaction at the interface between the spreading P507 thin liquid Membrane and the Er(III) aqueous solution would result in the Marangoni convection along the interface, which is in favor of overcoming the resistance from the viscous force when the surface tension gradient replaces gravity as a dominant driving force for the spreading. The present work provides an experimental foundation toward understanding the effect of the interfacial chemical reaction on the spreading behavior of an organic oil droplet on the gas-water interface. It is beneficial for the development of our suggested new technique of bubbling organic liquid Membrane Extraction and to achieve a controllable generation of a stable gas bubble-supported organic liquid Membrane for performing solvent Extraction at large aqueous-to-oil phase ratios.

  • Chemical Reaction-Driven Spreading of an Organic Extractant on the Gas–Water Interface: Insight into the Controllable Formation of a Gas Bubble-Supported Organic Extractant Liquid Membrane
    2019
    Co-Authors: Jie Liu, Kun Huang, Wenqian Liu, Huizhou Liu
    Abstract:

    The Extraction and recovery of low-concentration valuable metals from various complex aqueous solutions or industrial waste waters have attracted extensive interests in recent years. In our previous works, we suggested a novel technique called bubbling organic liquid Membrane Extraction by spreading and covering an organic extractant with extremely small volume on the surface of gas bubbles to form a layer of the gas bubble-supported organic liquid Membrane for selective Extraction and enrichment of low-concentration targets from dilute aqueous solutions. It was found that for successfully performing the bubbling organic liquid Membrane Extraction, a prerequisite is knowing how to control the formation of a stable organic liquid Membrane covered on the surface of gas bubbles. However, once the organic extractant starts to spread on the surface of gas bubbles, the Extraction chemical reaction at the interface between the organic extractant liquid Membrane and the rare-earth aqueous solution will occur. In the present work, the spreading behavior of the organic extractant P507 on the surface of rare-earth aqueous solutions was investigated and was compared with the behaviors on the surface of deionized water. It was revealed that the spreading of the organic extractant P507 on the surface of aqueous solutions containing rare-earth ions was accelerated because of the occurrence of the chemical reactions at the gas–water interface. The difference in the spreading rate of organic extractant P507 liquid droplets on the surface of deionized water and on that of Er­(III) aqueous solutions with an increase in the P507 concentration, the saponification degrees of the P507 extractant, and the preloading amount of Er­(III) in the P507 extractant revealed that the chemical reaction at the interface between the spreading P507 thin liquid Membrane and the Er­(III) aqueous solution would result in the Marangoni convection along the interface, which is in favor of overcoming the resistance from the viscous force when the surface tension gradient replaces gravity as a dominant driving force for the spreading. The present work provides an experimental foundation toward understanding the effect of the interfacial chemical reaction on the spreading behavior of an organic oil droplet on the gas–water interface. It is beneficial for the development of our suggested new technique of bubbling organic liquid Membrane Extraction and to achieve a controllable generation of a stable gas bubble-supported organic liquid Membrane for performing solvent Extraction at large aqueous-to-oil phase ratios

  • enrichment of low concentration rare earths from leach solutions of ion adsorption ores by bubbling organic liquid Membrane Extraction using n1923
    ACS Sustainable Chemistry & Engineering, 2017
    Co-Authors: Jie Liu, Kun Huang, Huizhou Liu
    Abstract:

    A new bubbling organic liquid Membrane Extraction using primary amine N1923 at large aqueous-to-oil phase ratios was suggested to extract and enrich extremely low concentration rare earths from the acidic sulfate leach solutions of ion-absorbing type rare-earth ores. It was revealed that bubbling organic liquid Membrane Extraction was in fact an interfacial chemical reaction of organic extractant molecules absorbing at the surface of the organic liquid Membrane supported by gas bubbles with the target metal ions in the aqueous solutions. Rare earths with a concentration about 100 mg/L can be extracted selectively and enriched efficiently into the organic extractant liquid Membrane layer covered on the surface of dispersed gas bubbles. However, Al in leach solutions was not extractable and remained in the raffinates, due to a kinetic nonequilibrium separation behavior of rare earths and Al on the surface of the organic liquid Membrane. It was the differences in reaction rate of rare earths and Al with prim...

Huizhou Liu - One of the best experts on this subject based on the ideXlab platform.

  • chemical reaction driven spreading of an organic extractant on the gas water interface insight into the controllable formation of a gas bubble supported organic extractant liquid Membrane
    Langmuir, 2019
    Co-Authors: Jie Liu, Kun Huang, Wenqian Liu, Huizhou Liu
    Abstract:

    The Extraction and recovery of low-concentration valuable metals from various complex aqueous solutions or industrial waste waters have attracted extensive interests in recent years. In our previous works, we suggested a novel technique called bubbling organic liquid Membrane Extraction by spreading and covering an organic extractant with extremely small volume on the surface of gas bubbles to form a layer of the gas bubble-supported organic liquid Membrane for selective Extraction and enrichment of low-concentration targets from dilute aqueous solutions. It was found that for successfully performing the bubbling organic liquid Membrane Extraction, a prerequisite is knowing how to control the formation of a stable organic liquid Membrane covered on the surface of gas bubbles. However, once the organic extractant starts to spread on the surface of gas bubbles, the Extraction chemical reaction at the interface between the organic extractant liquid Membrane and the rare-earth aqueous solution will occur. In the present work, the spreading behavior of the organic extractant P507 on the surface of rare-earth aqueous solutions was investigated and was compared with the behaviors on the surface of deionized water. It was revealed that the spreading of the organic extractant P507 on the surface of aqueous solutions containing rare-earth ions was accelerated because of the occurrence of the chemical reactions at the gas-water interface. The difference in the spreading rate of organic extractant P507 liquid droplets on the surface of deionized water and on that of Er(III) aqueous solutions with an increase in the P507 concentration, the saponification degrees of the P507 extractant, and the preloading amount of Er(III) in the P507 extractant revealed that the chemical reaction at the interface between the spreading P507 thin liquid Membrane and the Er(III) aqueous solution would result in the Marangoni convection along the interface, which is in favor of overcoming the resistance from the viscous force when the surface tension gradient replaces gravity as a dominant driving force for the spreading. The present work provides an experimental foundation toward understanding the effect of the interfacial chemical reaction on the spreading behavior of an organic oil droplet on the gas-water interface. It is beneficial for the development of our suggested new technique of bubbling organic liquid Membrane Extraction and to achieve a controllable generation of a stable gas bubble-supported organic liquid Membrane for performing solvent Extraction at large aqueous-to-oil phase ratios.

  • Chemical Reaction-Driven Spreading of an Organic Extractant on the Gas–Water Interface: Insight into the Controllable Formation of a Gas Bubble-Supported Organic Extractant Liquid Membrane
    2019
    Co-Authors: Jie Liu, Kun Huang, Wenqian Liu, Huizhou Liu
    Abstract:

    The Extraction and recovery of low-concentration valuable metals from various complex aqueous solutions or industrial waste waters have attracted extensive interests in recent years. In our previous works, we suggested a novel technique called bubbling organic liquid Membrane Extraction by spreading and covering an organic extractant with extremely small volume on the surface of gas bubbles to form a layer of the gas bubble-supported organic liquid Membrane for selective Extraction and enrichment of low-concentration targets from dilute aqueous solutions. It was found that for successfully performing the bubbling organic liquid Membrane Extraction, a prerequisite is knowing how to control the formation of a stable organic liquid Membrane covered on the surface of gas bubbles. However, once the organic extractant starts to spread on the surface of gas bubbles, the Extraction chemical reaction at the interface between the organic extractant liquid Membrane and the rare-earth aqueous solution will occur. In the present work, the spreading behavior of the organic extractant P507 on the surface of rare-earth aqueous solutions was investigated and was compared with the behaviors on the surface of deionized water. It was revealed that the spreading of the organic extractant P507 on the surface of aqueous solutions containing rare-earth ions was accelerated because of the occurrence of the chemical reactions at the gas–water interface. The difference in the spreading rate of organic extractant P507 liquid droplets on the surface of deionized water and on that of Er­(III) aqueous solutions with an increase in the P507 concentration, the saponification degrees of the P507 extractant, and the preloading amount of Er­(III) in the P507 extractant revealed that the chemical reaction at the interface between the spreading P507 thin liquid Membrane and the Er­(III) aqueous solution would result in the Marangoni convection along the interface, which is in favor of overcoming the resistance from the viscous force when the surface tension gradient replaces gravity as a dominant driving force for the spreading. The present work provides an experimental foundation toward understanding the effect of the interfacial chemical reaction on the spreading behavior of an organic oil droplet on the gas–water interface. It is beneficial for the development of our suggested new technique of bubbling organic liquid Membrane Extraction and to achieve a controllable generation of a stable gas bubble-supported organic liquid Membrane for performing solvent Extraction at large aqueous-to-oil phase ratios

  • enrichment of low concentration rare earths from leach solutions of ion adsorption ores by bubbling organic liquid Membrane Extraction using n1923
    ACS Sustainable Chemistry & Engineering, 2017
    Co-Authors: Jie Liu, Kun Huang, Huizhou Liu
    Abstract:

    A new bubbling organic liquid Membrane Extraction using primary amine N1923 at large aqueous-to-oil phase ratios was suggested to extract and enrich extremely low concentration rare earths from the acidic sulfate leach solutions of ion-absorbing type rare-earth ores. It was revealed that bubbling organic liquid Membrane Extraction was in fact an interfacial chemical reaction of organic extractant molecules absorbing at the surface of the organic liquid Membrane supported by gas bubbles with the target metal ions in the aqueous solutions. Rare earths with a concentration about 100 mg/L can be extracted selectively and enriched efficiently into the organic extractant liquid Membrane layer covered on the surface of dispersed gas bubbles. However, Al in leach solutions was not extractable and remained in the raffinates, due to a kinetic nonequilibrium separation behavior of rare earths and Al on the surface of the organic liquid Membrane. It was the differences in reaction rate of rare earths and Al with prim...

Guibin Jiang - One of the best experts on this subject based on the ideXlab platform.

  • evaluation of an on line coupled continuous flow liquid Membrane Extraction and precolumn system as trace enrichment technique by liquid chromatographic determination of bisphenol a
    Talanta, 2003
    Co-Authors: Jingfu Liu, Guibin Jiang, Xia Liang, Yaqi Cai, Qingxiang Zhou, Guoguang Liu
    Abstract:

    An on-line coupled continuous flow liquid Membrane Extraction (CFLME) and C-18 precolumn system was developed for sample preconcentration in liquid chromatography determination. After preconcentration by CFLME, which is based on the combination of continuous flow liquid-liquid Extraction and supported liquid Membrane, bisphenol A (BPA) was enriched in 960 mul of 1 mol l(-1) NaOH used as acceptor. This acceptor was on-line neutralized and transported onto the C-18 precolumn where analytes were absorbed and focused. Then the focused analytes were injected onto a C-18 analytical column for separation and detected at 220 nm with a diode array detector. CFLME related parameters such as flow rates, pH of donor and acceptor, and enrichment time were optimized. The proposed method presents a detection limit of 0.03 mug l(-1) (S/N = 3) when 60 ml samples was enriched with an enrichment time of 30 min. Compared with C-18 based column-switching procedure, this proposed procedure presents similar sample throughput and lower detection limits. The proposed method was successfully applied to determine BPA in tap water, river water, and municipal sewage effluent samples. (C) 2003 Elsevier B.V. All rights reserved.

  • continuous flow liquid Membrane Extraction a novel automatic trace enrichment technique based on continuous flow liquid liquid Extraction combined with supported liquid Membrane
    Analytica Chimica Acta, 2002
    Co-Authors: Jingfu Liu, Jingbo Chao, Guibin Jiang
    Abstract:

    Combining the continuous flow liquid-liquid Extraction (CFLLE) and supported liquid Membrane (SLM) Extraction, a novel aqueous-aqueous Extraction technique that we termed continuous flow liquid Membrane Extraction (CFLME) is developed for trace-enrichment. The analyte was firstly extracted into the organic phase in the CFLLE step, then transported onto the organic liquid Membrane that formed on the surface of the micro porous Membrane of the SLM equipment. Finally, it passed through the liquid Membrane and was trapped by the acceptor. Aspects related to CFLME were studied by using dichloromethane as liquid Membrane, and sulfonylurea herbicides as model compounds. An enrichment factor of over 1000 was obtained when 10 mug l(-1) of MSM was enriched for 120 min by this technique. The drawbacks of only a few organic solvents can be selected as liquid Membrane with a limited lifetime in SLM operation was overcome. In this CFLME method, almost all solvents that used in the conventional liquid-liquid Extraction (LLE) can be adopted and the lifetime of liquid Membrane is no longer a problem. (C) 2002 Elsevier Science B.V. All rights reserved.

  • automatic trace enrichment of bisphenol a by a novel continuous flow liquid Membrane Extraction technique
    Journal of Separation Science, 2001
    Co-Authors: Jingfu Liu, Jingbo Chao, Meijuan Wen, Guibin Jiang
    Abstract:

    Bisphenol A was enriched by a novel continuous flow liquid Membrane Extraction technique, which is based on the combination of continuous flow liquid-liquid Extraction and a supported liquid Membrane. Related parameters such as flow rates, liquid Membrane solvents, and pH of donor and acceptor were optimized. Using dichloromethane as liquid Membrane, over 200-fold enrichment of 50 mug L-1 BPA was obtained after a 40-min enrichment time. The major advantages of this technique are that it provides a relatively high enrichment factor, freedom of choice and long term stability of the liquid Membrane, much lower consumption of organic phase, typically 0.05 mL min(-1), scope for full automation, and easy on-line coupling to various detectors.

Jie Liu - One of the best experts on this subject based on the ideXlab platform.

  • chemical reaction driven spreading of an organic extractant on the gas water interface insight into the controllable formation of a gas bubble supported organic extractant liquid Membrane
    Langmuir, 2019
    Co-Authors: Jie Liu, Kun Huang, Wenqian Liu, Huizhou Liu
    Abstract:

    The Extraction and recovery of low-concentration valuable metals from various complex aqueous solutions or industrial waste waters have attracted extensive interests in recent years. In our previous works, we suggested a novel technique called bubbling organic liquid Membrane Extraction by spreading and covering an organic extractant with extremely small volume on the surface of gas bubbles to form a layer of the gas bubble-supported organic liquid Membrane for selective Extraction and enrichment of low-concentration targets from dilute aqueous solutions. It was found that for successfully performing the bubbling organic liquid Membrane Extraction, a prerequisite is knowing how to control the formation of a stable organic liquid Membrane covered on the surface of gas bubbles. However, once the organic extractant starts to spread on the surface of gas bubbles, the Extraction chemical reaction at the interface between the organic extractant liquid Membrane and the rare-earth aqueous solution will occur. In the present work, the spreading behavior of the organic extractant P507 on the surface of rare-earth aqueous solutions was investigated and was compared with the behaviors on the surface of deionized water. It was revealed that the spreading of the organic extractant P507 on the surface of aqueous solutions containing rare-earth ions was accelerated because of the occurrence of the chemical reactions at the gas-water interface. The difference in the spreading rate of organic extractant P507 liquid droplets on the surface of deionized water and on that of Er(III) aqueous solutions with an increase in the P507 concentration, the saponification degrees of the P507 extractant, and the preloading amount of Er(III) in the P507 extractant revealed that the chemical reaction at the interface between the spreading P507 thin liquid Membrane and the Er(III) aqueous solution would result in the Marangoni convection along the interface, which is in favor of overcoming the resistance from the viscous force when the surface tension gradient replaces gravity as a dominant driving force for the spreading. The present work provides an experimental foundation toward understanding the effect of the interfacial chemical reaction on the spreading behavior of an organic oil droplet on the gas-water interface. It is beneficial for the development of our suggested new technique of bubbling organic liquid Membrane Extraction and to achieve a controllable generation of a stable gas bubble-supported organic liquid Membrane for performing solvent Extraction at large aqueous-to-oil phase ratios.

  • Chemical Reaction-Driven Spreading of an Organic Extractant on the Gas–Water Interface: Insight into the Controllable Formation of a Gas Bubble-Supported Organic Extractant Liquid Membrane
    2019
    Co-Authors: Jie Liu, Kun Huang, Wenqian Liu, Huizhou Liu
    Abstract:

    The Extraction and recovery of low-concentration valuable metals from various complex aqueous solutions or industrial waste waters have attracted extensive interests in recent years. In our previous works, we suggested a novel technique called bubbling organic liquid Membrane Extraction by spreading and covering an organic extractant with extremely small volume on the surface of gas bubbles to form a layer of the gas bubble-supported organic liquid Membrane for selective Extraction and enrichment of low-concentration targets from dilute aqueous solutions. It was found that for successfully performing the bubbling organic liquid Membrane Extraction, a prerequisite is knowing how to control the formation of a stable organic liquid Membrane covered on the surface of gas bubbles. However, once the organic extractant starts to spread on the surface of gas bubbles, the Extraction chemical reaction at the interface between the organic extractant liquid Membrane and the rare-earth aqueous solution will occur. In the present work, the spreading behavior of the organic extractant P507 on the surface of rare-earth aqueous solutions was investigated and was compared with the behaviors on the surface of deionized water. It was revealed that the spreading of the organic extractant P507 on the surface of aqueous solutions containing rare-earth ions was accelerated because of the occurrence of the chemical reactions at the gas–water interface. The difference in the spreading rate of organic extractant P507 liquid droplets on the surface of deionized water and on that of Er­(III) aqueous solutions with an increase in the P507 concentration, the saponification degrees of the P507 extractant, and the preloading amount of Er­(III) in the P507 extractant revealed that the chemical reaction at the interface between the spreading P507 thin liquid Membrane and the Er­(III) aqueous solution would result in the Marangoni convection along the interface, which is in favor of overcoming the resistance from the viscous force when the surface tension gradient replaces gravity as a dominant driving force for the spreading. The present work provides an experimental foundation toward understanding the effect of the interfacial chemical reaction on the spreading behavior of an organic oil droplet on the gas–water interface. It is beneficial for the development of our suggested new technique of bubbling organic liquid Membrane Extraction and to achieve a controllable generation of a stable gas bubble-supported organic liquid Membrane for performing solvent Extraction at large aqueous-to-oil phase ratios

  • enrichment of low concentration rare earths from leach solutions of ion adsorption ores by bubbling organic liquid Membrane Extraction using n1923
    ACS Sustainable Chemistry & Engineering, 2017
    Co-Authors: Jie Liu, Kun Huang, Huizhou Liu
    Abstract:

    A new bubbling organic liquid Membrane Extraction using primary amine N1923 at large aqueous-to-oil phase ratios was suggested to extract and enrich extremely low concentration rare earths from the acidic sulfate leach solutions of ion-absorbing type rare-earth ores. It was revealed that bubbling organic liquid Membrane Extraction was in fact an interfacial chemical reaction of organic extractant molecules absorbing at the surface of the organic liquid Membrane supported by gas bubbles with the target metal ions in the aqueous solutions. Rare earths with a concentration about 100 mg/L can be extracted selectively and enriched efficiently into the organic extractant liquid Membrane layer covered on the surface of dispersed gas bubbles. However, Al in leach solutions was not extractable and remained in the raffinates, due to a kinetic nonequilibrium separation behavior of rare earths and Al on the surface of the organic liquid Membrane. It was the differences in reaction rate of rare earths and Al with prim...