Preparation of Chemically Resistant Cellulose Benzoate Hollow Fiber Membrane via Thermally Induced Phase Separation Method

Shota Takao; Saeid Rajabzadeh; Masahide Shibata; Chihiro Otsubo; Toyozo Hamada; Noriaki Kato; Keizo Nakagawa; Tooru Kitagawa; Hideto Matsuyama; Tomohisa Yoshioka

doi:10.3390/membranes12121199

Preparation of Chemically Resistant Cellulose Benzoate Hollow Fiber Membrane via Thermally Induced Phase Separation Method

Membranes (Basel). 2022 Nov 28;12(12):1199. doi: 10.3390/membranes12121199.

Authors

Shota Takao^{1

2}, Saeid Rajabzadeh^{3

4

5}, Masahide Shibata¹, Chihiro Otsubo¹, Toyozo Hamada¹, Noriaki Kato^{3

4}, Keizo Nakagawa^{2

3}, Tooru Kitagawa^{2

3}, Hideto Matsuyama^{3

4}, Tomohisa Yoshioka^{2

3}

Affiliations

¹ Daicel Co., Ltd., 1239 Shinzaike, Aboshi-ku, Himeji 671-1283, Japan.
² Graduate School of Science, Technology and Innovation, Kobe University, 1-1 Rokkodai, Nada, Kobe 657-8501, Japan.
³ Research Center for Membrane and Film Technology, Kobe University, 1-1 Rokkodai, Nada, Kobe 657-8501, Japan.
⁴ Department of Chemical Science and Engineering, Kobe University, 1-1 Rokkodai, Nada, Kobe 657-8501, Japan.
⁵ School of Civil and Environmental Engineering, University of Technology Sydney (UTS), City Campus, Broadway, Ultimo, NSW 2007, Australia.

Abstract

For the first time, we have successfully fabricated microfiltration (MF) hollow fiber membranes by the thermally induced phase separation (TIPS) and non-solvent induced phase separation (NIPS) methods using cellulose acetate benzoate (CBzOH), which is a cellulose derivative with considerable chemical resistance. To obtain an appropriate CBzOH TIPS membrane, a comprehensive solvent screening was performed to choose the appropriate solvent to obtain a membrane with a porous structure. In parallel, the CBzOH membrane was prepared by the NIPS method to compare and evaluate the effect of membrane structure using the same polymer material. Prepared CBzOH membrane by TIPS method showed high porosity, pore size around 100 nm or larger and high pure water permeability (PWP) with slightly low rection performance compared to that by NIPS. On the contrary, CBzOH membranes prepared with the NIPS method showed three times lower PWP with higher rejection. The chemical resistance of the prepared CBzOH membranes was compared with that of cellulose triacetate (CTA) hollow fiber membrane, which is a typical cellulose derivative as a control membrane, using a 2000 ppm sodium hypochlorite (NaClO) solution. CBzOH membranes prepared with TIPS and NIPS methods showed considerable resistance against the NaClO solution regardless of the membrane structure, porosity and pore size. On the other hand, when the CTA membrane, as the control membrane, was subjected to the NaClO solution, membrane mechanical strength sharply decreased over the exposure time to NaClO. It is interesting that although the CBzOH TIPS membrane showed three times higher pure water permeability than other membranes with slightly lower rejection and considerably higher NaClO resistance, the mechanical strength of this membrane is more than two times higher than other membranes. While CBzOH samples showed no change in chemical structure and contact angle, CTA showed considerable change in chemical structure and a sharp decrease in contact angle after treatment with NaClO. Thus, CBzOH TIPS hollow fiber membrane is noticeably interesting considering membrane performance in terms of filtration performance, mechanical strength and chemical resistance on the cost of slightly losing rejection performance.

Keywords: cellulose acetate benzoate (CBzOH); chlorine resistance; hollow fiber membrane; microfiltration; thermally induced phase separation.

Grants and funding

This work was partially supported by Kobe University Strategic International Collaborative Research Grant (Type B Fostering Joint Research).