(472g) Simulations and Experiments Validation on the Membrane Based Response Technology for Nucleation Detection and Crystallization Control

Simulations and Experiments validation on the Membrane
based Response Technology for Nucleation Detection and Crystallization Control

Xiaobin Jiang, Wu Xiao, Dapeng Lu, Rui Zhao, Gaohong
He*

State Key Laboratory of Fine
Chemicals, School of Chemical Engineering, Petrochemical Energy-efficient
Separation Technology Engineering Lab of Liaoning Province, Dalian University
of Technology, Dalian, P. R. China

*Corresponding author: Email: hgaohong@dlut.edu.cn

Abstract

The mass
transfer flux decline and the crystallization on the membrane interface is often
considered as a fouling behavior [1,2]. For now, non-attention had been paid on
applying this sensitive nucleation response phenomenon for the crystal nucleus detection.
While, the inevitable nucleation on the membrane interface under certain
operational conditions inspired us that the membrane interface could perform as
the response medium of the nucleation detection. The responding mechanism is
constructed base on the chain effect of ¡®nucleation on the pores of the membrane interface-transmembrane flux sharply decrease¡¯. The inflection
point of the transmembrane flux confirms the nucleation timing on the membrane
interface. The accurate recording of the transmembrane flux data can be
utilized to calculate the solution concentration to determine the metastable
zone width (MSZW), which is key data to determine the crystallizaiton operative
window [3,4].

Obviously, without relying on the optical signal, membrane
based nucleation response method would be easy and more meaningful in the case
of opaque solutions that laser intensity response method is invalid [5]. This
advantage will improve the controlling accuracy and flexibility during MSZW
measurement. Moreover, with the proposed method, it is easy to enhance control
over the process. The real operative conditions during crystallizaiton can be achieved
in this membrane based technology. Detailed
simulations and experiments on the typical binary aqueous solution systems were
implemented to represent the role of T_f, T_p
and A/V₀ on the supersaturation degree adjustment.

In addition, it
also reported that the polymer interface with nanometer scale pores had significant
impact of on inducing crystallization and polymorphism control [6,7]. The
foundational work can promote the theoretical research and application of the
MDC based nucleation response and crystallization control by providing the
qualified microporous membrane as desired nucleation detection and response
interface.

Acknowledgment

We acknowledge fnancial contribution from
from National Natural Science Foundation of China (Grant No. 21527812,
21676043, U1663223), Changjiang Scholars Program (T2012049), the
Fundamental Research Funds for the Central Universities (DUT16TD19) and
Education Department of the Liaoning Province of China (No. LT2015007).

References

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