Demulsification of W/O emulsion with three-dimensional electric spiral plate-type microchannel

doi:10.11949/j.issn.0438-1157.20161732

Abstract

Abstract:

A set of three-dimensional electric spiral plate-type microchannels (3D-ESPM) was designed and fabricated for the first time. The microchannel is comprised of amphiphilic copper plates and lipophilic polytetrafluoroethylene (PTFE) plates. By coupling electric demulsification and microfluidic demulsification, the microchannel can efficiently demulsify a W/O emulsion. Factors influencing the demulsification of W/O emulsion using 3D-ESPM were systematically investigated, including the height of the microchannel, the number of microchannel plates, the spiral angle of the microchannel, the electric field intensity and the flow rate of the emulsion. The results showed that demulsification efficiency increases with increasing electric field intensity, decreasing microchannel height, and increasing microchannel length. The maximum demulsification efficiency of W/O emulsion in a single pass through the 3D-ESPM reached 68% with a microchannel height of 110 μm, electric field intensity of 250 V·cm^-1, microchannel angle of 180°, microchannel number of 5, and flow rate of 2 ml·min^-1. The results showed that 3D-ESPM can intensify the demulsification of W/O emulsion.

Key words: emulsions, microchannels, separation

摘要：

首次设计并加工了一套加电三维螺旋板式微通道装置，微通道由具有双亲性的铜片与亲油性的聚四氟乙烯（PTFE）片构成，该装置利用电破乳与微通道破乳的双重耦合作用，可以实现微通道对W/O型乳状液的高效破乳过程。实验研究了该通道对W/O型乳状液的破乳效果，主要考察了微通道高度、微通道片数、微通道螺旋角度、直流电场强度以及乳状液流速等因素对破乳率的影响。实验结果表明：减小通道高度、增加通道长度、提高电场强度有助于提升微通道的破乳率；当微通道高度为110 μm、直流电场强度为250 V·cm^-1、微通道角度为180°、微通道片数为5片、流速为2 ml·min^-1时乳状液单次通过微通道的破乳率可以达到68%。实验结果表明加电三维螺旋微通道对W/O型乳状液的破乳过程具有过程强化作用。

关键词: 乳液, 微通道, 分离

CLC Number:

TQ028.8

PU Yadong, RUAN Da, DILIYAER·Hamiti, ZHAO Zhigang, CHEN Xiao. Demulsification of W/O emulsion with three-dimensional electric spiral plate-type microchannel[J]. CIESC Journal, 2017, 68(7): 2790-2797.

蒲亚东, 阮达, 地力亚尔·哈米提, 赵志刚, 陈晓. 加电三维螺旋板式微通道对W/O型乳状液的破乳[J]. 化工学报, 2017, 68(7): 2790-2797.

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