Experimental Investigation of Liquid-liquid Extraction and Gas-liquid-liquid Flow in a Microchannel

Document Type : Research Paper

Authors

Department of Chemical Engineering, Isfahan University of Technology, Iran

Abstract

In this study, solvent extraction during gas-liquid-liquid flow in a microchannel was investigated. Sodium hydroxide aqueous solution, acetic acid dissolved in n-hexane and nitrogen were employed as the aqueous, organic and gaseous phases, respectively. The microchannel was made of glass with a cross sectional dimension of 800×700 µm2. In the two-phase mode (without the gas phase), the flow regime was slug flow, while in the three-phase flow mode, the flow pattern was a double emulsion (gas in organic in water) flow. By increasing the total fluid flow from 0.005 to 0.020 mL/s, the overall volumetric mass transfer coefficient enhanced on average by 140%. Using the gas phase did not always improve the mass transfer coefficient in the microchannel. For example, at a constant liquids flow rate of 0.005 mL/s, increasing the gas flow rate from 0 to 0.1 mL/s, deteriorated the mass transfer coefficient, however, increasing the gas flow rate up to 0.2 mL/s led to augmentation of the mass transfer coefficient.
 

Keywords


[1]. Tang J, Zhang X, Cai W, Wang F (2013) Liquid-liquid extraction based on droplet flow in a vertical microchannel, Experimental Thermal and Fluid Science, 49: 185-192. ##
[2]. Kashid M N, Renken A, Kiwi-Minsker L (2011) Gas-liquid and liquid-liquid mass transfer in microstructured reactors, Chemical Engineering Science, 66, 17: 3876-3897. ##
[3]. Assmann N, von Rohr P R (2011) Extraction in microreactors: Intensification by adding an inert gas phase, Chemical engineering and processing: process intensification, 50, 8: 822-827. ##
[4]. Hao Y, Jin N, Wang Q, Zhou Y, Zhao Y, Zhang X, Lü H (2020) Dynamics and controllability of droplet fusion under gas–liquid-liquid three-phase flow in a microfluidic reactor, RSC Advances, 10, 24: 14322-14330. ##
[5]. Yue J, Rebrov E, Schouten J (2014) Gas-liquid-liquid three-phase flow pattern and pressure drop in a microfluidic chip: Similarities with gas-liquid/liquid-liquid flows, Lab on a Chip, 14, 632-1649. ##
[6]. Di Miceli Raimondi N., Prat L, Gourdon C, Tasselli J (2014) Experiments of mass transfer with liquid-liquid slug flow in square microchannels, Chemical Engineering Science, 105: 169-178. ##
[7]. Tsaoulidis D, Angeli P (2015) Effect of channel size on mass transfer during liquid-liquid plug flow in small scale extractors, Chemical Engineering Journal, 262: 785-793. ##
[8]. Zhao Y, Su Y, Chen G, Yuan Q (2010) Effect of surface properties on the flow characteristics and mass transfer performance in microchannels, Chemical Engineering Science, 65, 5: 1563-1570. ##
[9]. Burns J R, Ramshaw C (2001) The intensification of rapid reactions in multiphase systems using slug flow in capillaries, Lab on a Chip, 1, 1: 10-15. ##
[10]. Dessimoz A L, Cavin L, Renken A, Kiwi-Minsker L (2008) Liquid–liquid two-phase flow patterns and mass transfer characteristics in rectangular glass microreactors, Chemical Engineering Science, 63, 16: 4035-4044. ##
[11]. Sattari-Najafabadi M, Nasr Esfahany M, Wu Z, Sundén B (2017) Hydrodynamics and mass transfer in liquid-liquid non-circular microchannels: Comparison of two aspect ratios and three junction structures, Chemical Engineering Journal, 322: 328-338. ##
[12]. Sattari-Najafabadi M, Sundén B, Wu Z, Nasr Esfahany M (2016) Influence of physical properties of phases on hydrodynamics and mass transfer characteristics of a liquid-liquid circular microchannel, International conference on nanochannels, microchannels, and minichannels, ICNMM2016-7954, V001T03A003, Washington. ##
[13]. Liu Y, Chen G, Yue J (2020) Manipulation of gas-liquid-liquid systems in continuous flow microreactors for efficient reaction processes, Journal of Flow Chemistry, 10, 1: 103-121. ##
[14]. Su Y, Chen G, Zhao Y, Yuan Q (2009) Intensification of liquid–liquid two-phase mass transfer by gas agitation in a microchannel, AIChE Journal, 55, 8: 1948-1958. ##
[15]. Yao C, Ma H, Zhao Q, Liu Y, Zhao Y, Chen G (2020) Mass transfer in liquid-liquid Taylor flow in a microchannel: Local concentration distribution, mass transfer regime and the effect of fluid viscosity, Chemical Engineering Science, 223: 115734. ##
[16]. Yao C, Liu Y, Zhao S, Dong Z, Chen G (2017) Bubble/droplet formation and mass transfer during gas–liquid-liquid segmented flow with soluble gas in a microchannel, AIChE Journal, 63, 5: 1727-1739. ##
[17]. Rui Ma, Fan C, Wang Y, Luo J, Li J, Komarneni S (2020) Gas-Liquid-liquid Extraction in a Novel Rotating Microchannel Extraction, Chinese Journal of Chemical Engineering, 28: 2523-2532. ##
[18]. Aoki N, Ando R, Mae K (2011) Gas-liquid-liquid slug flow for improving liquid-liquid extraction in miniaturized channels, Industrial Engineering Chemical Research, 50: 4672–4677. ##