SCI和EI收录∣中国化工学会会刊

Chinese Journal of Chemical Engineering ›› 2016, Vol. 24 ›› Issue (1): 86-93.DOI: 10.1016/j.cjche.2015.11.015

• 第25届中国过程控制会议专栏 • 上一篇    下一篇

An easily recoverable thermo-sensitive polyelectrolyte as draw agent for forward osmosis process

Yanni Wang1, Hairong Yu1, Rui Xie1, Kuangmin Zhao1, Xiaojie Ju1, WeiWang1, Zhuang Liu1, Liangyin Chu1,2   

  1. 1 School of Chemical Engineering, Sichuan University, Chengdu 610065, China;
    2 State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu 610065, China
  • 收稿日期:2014-09-23 修回日期:2015-08-05 出版日期:2016-01-28 发布日期:2016-02-23
  • 通讯作者: Rui Xie, Liangyin Chu
  • 基金资助:

    Supported by the National Natural Science Foundation of China (21276162) and the Program for Yangtse River Scholars and Innovative Research Team in Universities (IRT1163).

An easily recoverable thermo-sensitive polyelectrolyte as draw agent for forward osmosis process

Yanni Wang1, Hairong Yu1, Rui Xie1, Kuangmin Zhao1, Xiaojie Ju1, WeiWang1, Zhuang Liu1, Liangyin Chu1,2   

  1. 1 School of Chemical Engineering, Sichuan University, Chengdu 610065, China;
    2 State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu 610065, China
  • Received:2014-09-23 Revised:2015-08-05 Online:2016-01-28 Published:2016-02-23
  • Contact: Rui Xie, Liangyin Chu
  • Supported by:

    Supported by the National Natural Science Foundation of China (21276162) and the Program for Yangtse River Scholars and Innovative Research Team in Universities (IRT1163).

摘要: As a potential solution to the crises of energy and resources, forward osmosis (FO) has been limited by the development of draw agents. An ideal draw agent should be able to generate high osmotic pressure and can be easily recovered. In this study, a thermo-sensitive polyelectrolyte of poly(N-isopropylacrylamide-co-acrylic acid) (PNA) is developed as an efficient drawagent, and two easy and simple methods are proposed to effectively recover the polyelectrolytes. After adjusting the pH value of polyelectrolyte solutions to around 6.0, the polyelectrolyte can generate relatively high osmotic pressure, and induce average water fluxes of 2.09 and 2.95 L·m-2·h-1 during 12 h FO processes when the polyelectrolyte concentrations are 0.20 and 0.38 g·ml-1 respectively. After acidifying and heating to 70 ℃, the PNA-10 polyelectrolyte can aggregate together because of hydrophobic association and separate from water, so it can be easily recovered by either simple centrifugation or gravitational sedimentation. The recovery ratios of PNA-10 polyelectrolyte in both methods are as high as 89%, and the recovered polyelectrolytes can be reused with almost the same FO performance as fresh ones. The results in this study provide valuable guidance for designing efficient and easily recoverable draw agents for FO processes.

关键词: Forward osmosis, Draw agent, Thermo-sensitive polyelectrolyte, Recovery method, Poly(N-isopropylacrylamide-co-acrylic acid)

Abstract: As a potential solution to the crises of energy and resources, forward osmosis (FO) has been limited by the development of draw agents. An ideal draw agent should be able to generate high osmotic pressure and can be easily recovered. In this study, a thermo-sensitive polyelectrolyte of poly(N-isopropylacrylamide-co-acrylic acid) (PNA) is developed as an efficient drawagent, and two easy and simple methods are proposed to effectively recover the polyelectrolytes. After adjusting the pH value of polyelectrolyte solutions to around 6.0, the polyelectrolyte can generate relatively high osmotic pressure, and induce average water fluxes of 2.09 and 2.95 L·m-2·h-1 during 12 h FO processes when the polyelectrolyte concentrations are 0.20 and 0.38 g·ml-1 respectively. After acidifying and heating to 70 ℃, the PNA-10 polyelectrolyte can aggregate together because of hydrophobic association and separate from water, so it can be easily recovered by either simple centrifugation or gravitational sedimentation. The recovery ratios of PNA-10 polyelectrolyte in both methods are as high as 89%, and the recovered polyelectrolytes can be reused with almost the same FO performance as fresh ones. The results in this study provide valuable guidance for designing efficient and easily recoverable draw agents for FO processes.

Key words: Forward osmosis, Draw agent, Thermo-sensitive polyelectrolyte, Recovery method, Poly(N-isopropylacrylamide-co-acrylic acid)