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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