SCI和EI收录∣中国化工学会会刊

中国化学工程学报 ›› 2020, Vol. 28 ›› Issue (1): 114-121.DOI: 10.1016/j.cjche.2019.04.011

• Separation Science and Engineering • 上一篇    下一篇

Gradient nanoporous phenolics as substrates for high-flux nanofiltration membranes by layer-by-layer assembly of polyelectrolytes

Yazhi Yang, Qianqian Lan, Yong Wang   

  1. State Key Laboratory of Materials-Oriented Chemical Engineering, Jiangsu National Synergetic Innovation Center for Advanced Materials, College of Chemical Engineering, Nanjing Tech University, Nanjing 211816, China
  • 收稿日期:2019-02-26 修回日期:2019-04-02 出版日期:2020-01-28 发布日期:2020-03-31
  • 通讯作者: Yong Wang
  • 基金资助:
    Supported by the National Basic Research Program of China (2015CB655301), the Natural Science Foundation of China (21825803), and the Natural Science Foundation of Jiangsu Province (BK20150063), the Program of Excellent Innovation Teams of Jiangsu Higher Education Institutions, and the Project of Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD).

Gradient nanoporous phenolics as substrates for high-flux nanofiltration membranes by layer-by-layer assembly of polyelectrolytes

Yazhi Yang, Qianqian Lan, Yong Wang   

  1. State Key Laboratory of Materials-Oriented Chemical Engineering, Jiangsu National Synergetic Innovation Center for Advanced Materials, College of Chemical Engineering, Nanjing Tech University, Nanjing 211816, China
  • Received:2019-02-26 Revised:2019-04-02 Online:2020-01-28 Published:2020-03-31
  • Contact: Yong Wang
  • Supported by:
    Supported by the National Basic Research Program of China (2015CB655301), the Natural Science Foundation of China (21825803), and the Natural Science Foundation of Jiangsu Province (BK20150063), the Program of Excellent Innovation Teams of Jiangsu Higher Education Institutions, and the Project of Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD).

摘要: Thin film composite (TFC) membranes represent a highly promising platform for efficient nanofiltration (NF) processes. However, the improvement in permeance is impeded by the substrates with low permeances. Herein, highly permeable gradient phenolic membranes with tight selectivity are used as substrates to prepare TFC membranes with high permeances by the layer-by-layer assembly method. The negatively charged phenolic substrates are alternately assembled with polycation polyethylenimine (PEI) and polyanion poly(acrylic acid) (PAA) as a result of electrostatic interactions, forming thin and compact PEI/PAA layers tightly attached to the substrate surface. Benefiting from the high permeances and tight surface pores of the gradient nanoporous structures of the substrates, the produced PEI/PAA membranes exhibit a permeance up to 506 L·m-2·h-1·MPa-1, which is ~2-10 times higher than that of other membranes with similar rejections. The PEI/PAA membranes are capable of retaining >96.1% of negatively charged dyes following the mechanism of electrostatic repulsion. We demonstrate that the membranes can also separate positively and neutrally charged dyes from water via other mechanisms. This work opens a new avenue for the design and preparation of high-flux NF membranes, which is also applicable to enhance the permeance of other TFC membranes.

关键词: Nanofiltration membrane, Polyelectrolyte, Layer-by-layer assembly, High permeance, Gradient phenolic

Abstract: Thin film composite (TFC) membranes represent a highly promising platform for efficient nanofiltration (NF) processes. However, the improvement in permeance is impeded by the substrates with low permeances. Herein, highly permeable gradient phenolic membranes with tight selectivity are used as substrates to prepare TFC membranes with high permeances by the layer-by-layer assembly method. The negatively charged phenolic substrates are alternately assembled with polycation polyethylenimine (PEI) and polyanion poly(acrylic acid) (PAA) as a result of electrostatic interactions, forming thin and compact PEI/PAA layers tightly attached to the substrate surface. Benefiting from the high permeances and tight surface pores of the gradient nanoporous structures of the substrates, the produced PEI/PAA membranes exhibit a permeance up to 506 L·m-2·h-1·MPa-1, which is ~2-10 times higher than that of other membranes with similar rejections. The PEI/PAA membranes are capable of retaining >96.1% of negatively charged dyes following the mechanism of electrostatic repulsion. We demonstrate that the membranes can also separate positively and neutrally charged dyes from water via other mechanisms. This work opens a new avenue for the design and preparation of high-flux NF membranes, which is also applicable to enhance the permeance of other TFC membranes.

Key words: Nanofiltration membrane, Polyelectrolyte, Layer-by-layer assembly, High permeance, Gradient phenolic