(42d) Spatial Confined Capillary Flow Involved Model for Micro Droplet Crystallization and Particle Screening
AIChE Annual Meeting
2019
2019 AIChE Annual Meeting
Separations Division
Solid Form Selection: Cocrystals, Salts, Solvates, Polymorphs, and Beyond
Sunday, November 10, 2019 - 4:27pm to 4:45pm
Spatial
Confined Capillary Flow Involved Model for Micro Droplet Crystallization and
Particle Screening
Jin
Li, Mingguang Han, Xiaobin Jiang*, Gaohong He
State
Key Laboratory of Fine Chemicals, Research and Development Center of Membrane
Science and Technology, School of Chemical Engineering, Dalian University of
Technology, Dalian, P. R. China
*Corresponding
author: Email: xbjiang@dlut.edu.cn
Abstract
10.0pt;font-family:" arial>Droplet evaporative
crystallization and its relevant crystal phenomena in microscale space have
drown great attention recently in fine crystal manufature1-3, sensor
fabrication4, and biochemistry5, etc.,
due to its high precision in mass transfer and heat transfer controlling
characteristic. Several fabrication approaches have been reported in micro
scaled evaporative crystallization devices, and exhibit tremendous work in
advanced application, however, it hasn¡¯t drowned sufficient attention yet
especially for the theoretical research during droplet evaporation
crystallization. Here, we developed a droplet simplified model with
conventional evaporative model and nucleation models to handle the process
inside droplet evaporation crystallization, and predict crystal formation and
distribution according to the developed droplet model and crystal series
characteristics. Firstly, the main idea of droplet evaporation model is shown
in the Figure 1. A united step based evaporative model is raised to
predict potential crystallizing supersaturation by handling concentration and
nucleation energy distribution in further crystallization process.
(a) Droplet appearance during 4 evaporated condition. (b) The idea of united
step based evaporative model
10.0pt;font-family:" arial>To describe the superiority
of developed models, several inorganic crystal series like sodium urate monohydrate
(SUM) is invited in our work with various concentration and conventional
nucleation theory 6 (in
Figure 2). It could be apparently found that, droplet evaporation
crystallization model predicted nucleation energy barrier meet the result of
crystal distribution observed under higher precision scanning electronic microscopy.
Fig 2:
(a1~a4): Droplet nucleation distribution and (b1-b4): SUM crystal distribution
and crystal form from various concentration SUM series.
10.0pt;font-family:" arial>By means of conventional
evaporation stages raised by Shananhan7 and capillary
flow ¡°coffee ring¡± raised by Deegan8, we
sketched the crystal map by using NaCl series with various crystal concentration,
droplet condition and eventually formed crystal shape and distribution in Figure
3, leading to the high precision prediction as long as knowing
font-family:" arial>crystal series, concentration and
droplet condition. The controlling mechanism revealed in this work is also
contribute for the interfacial based crystallization and paritcle screening
process.
Fig 3:
Illustration of NaCl crystal shape, distribution, evaporate stages, capillary
flow and droplet condition.
Acknowledgment
10.0pt;font-family:" arial>We acknowledge the
financial contribution from National Natural Science Foundation of China (Grant
No. 21527812, 21676043, 21606035), the Fundamental Research Funds for the
Central Universities (DUT16TD19, DUT17ZD203) and MOST innovation team in key
area (No. 2016RA4053).
References
1. Teh
SY, Lin R, Hung LH, Lee AP. Droplet microfluidics. Lab on a chip. Feb
2008;8(2):198-220.