Abstract
The uneven permeation of cations and anions through forward osmosis membranes offers a new technical challenge in the development of forward osmosis processes. Cation exchange in polyamide thin film composite membranes is caused by carboxylic acid functional groups within the structure of these membranes' selective layers. These functional groups will gain or lose a proton depending on the external solution pH. The deprotonation of a polyamide at alkaline pHs results in a net negative charge, allowing for the exchange of cations between feed and draw solutions having monovalent cations. In this study, the importance of solution pH in influencing cation transport across a commercial thin film composite forward osmosis membrane was examined. It was found that cation transport across this membrane varies significantly with changes in pH and occurred fastest at alkaline pH.
| Original language | English |
|---|---|
| Pages (from-to) | 177-182 |
| Number of pages | 6 |
| Journal | Environmental Science and Technology Letters |
| Volume | 2 |
| Issue number | 7 |
| DOIs | |
| State | Published - Jul 6 2015 |
Bibliographical note
Publisher Copyright:© 2015 American Chemical Society.
Funding
| Funders | Funder number |
|---|---|
| Division of Chemical, Bioengineering, Environmental, and Transport Systems | |
| National Science Foundation Arctic Social Science Program | 1160069, 0947869, 1160098 |
| U.S. Environmental Protection Agency | R834872 |
ASJC Scopus subject areas
- Environmental Chemistry
- Ecology
- Water Science and Technology
- Waste Management and Disposal
- Pollution
- Health, Toxicology and Mutagenesis