A comparative study on electrosorptive rates of metal ions in capacitive deionization
Autor: | Yanting Li, Ty C. Stewart, Hao L. Tang |
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Rok vydání: | 2018 |
Předmět: |
inorganic chemicals
Capacitive deionization Chemistry Process Chemistry and Technology Metal ions in aqueous solution Inorganic chemistry Kinetics Ionic bonding 02 engineering and technology 010501 environmental sciences 021001 nanoscience & nanotechnology Alkali metal 01 natural sciences Desorption Electrode medicine 0210 nano-technology Safety Risk Reliability and Quality Waste Management and Disposal 0105 earth and related environmental sciences Biotechnology Activated carbon medicine.drug |
Zdroj: | Journal of Water Process Engineering. 26:257-263 |
ISSN: | 2214-7144 |
DOI: | 10.1016/j.jwpe.2018.10.021 |
Popis: | A comparative study on electrosorptive rates was conducted to explore the affinity preference of Na+, K+, Mg2+, Ca2+, Cd2+, Pb2+ and Cu2+ to activated carbon cloth electrodes of capacitive deionization (CDI) in mono-component solutions. Results showed the electrosorptive kinetics of these metal ions followed the Lagergren equation. For alkali and alkali-earth metal ions, the order of electrosorptive rates followed K+ > Na+ > Ca2+ > Mg2+, which revealed an inversely proportional relationship with their ionic hydrated radii. The relationship between electrosorptive rates and ionic hydrated radii, however, did not hold for heavy metal ions, and the order was Cu2+ > Pb2+ > Cd2+. The abnormal electrosorptive behaviors of Cu2+ and Pb2+ could be attributed to electrodeposition and formation of OH− complexes during electrosorption. Besides, Cu2+ and Pb2+ showed significantly low desorption efficiencies during the electrode regeneration processes, indicating serious electrode fouling during the electrosorptive process. This work provides fundamental aspects on individual removal of metal ions and the results can be beneficially used as a reference for treatment and recovery of metal ions by CDI technology. |
Databáze: | OpenAIRE |
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