Enhanced removal of I- on hierarchically structured layered double hydroxides by in suit growth of Cu/Cu2O.
J Environ Sci (China)
; 88: 338-348, 2020 Feb.
Article
in En
| MEDLINE
| ID: mdl-31862075
ABSTRACT
To further improve the removal ability of layered double hydroxide (LDH) for iodide (I-) anions from wastewater, we prepared hierarchically porous Cu5Mg10Al5-LDH and used as a matrix for in suit growth of Cu/Cu2O on its surface, forming Cu/Cu2O-LDH, which was characterized and applied as an adsorbent. Results displayed high I- saturation uptake capability (137.8 mg/g) of Cu/Cu2O-LDH compared with Cu5Mg10Al5-LDH (26.4 mg/g) even thermal activated LDH (76.1 mg/g). Thermodynamic analysis showed that the reaction between I- anions and Cu/Cu2O-LDH is a spontaneous and exothermic. Uptake kinetics analysis exhibited that adsorption equilibrium can be reached after 265 min. Additionally, the adsorbent showed satisfactory selectivity in the presence of competitive anions (e.g., SO42-), and could achieve good adsorption performance in a wide pH range of 3-8. A cooperative adsorption mechanism was proposed on the basis of the following two aspects (1) ion exchange between iodide and interlayer anions; (2) the adsorption performance of Cu, Cu(II) and Cu2O for I-. Meanwhile, the difference between the adsorption mechanism of Cu/Cu2O-LDH, Cu5Mg10Al5-LDH and Cu5Mg10Al5-CLDH adsorbents was also elaborated and verified.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Water Pollutants, Chemical
/
Waste Disposal, Fluid
/
Iodides
Language:
En
Journal:
J Environ Sci (China)
Journal subject:
SAUDE AMBIENTAL
Year:
2020
Document type:
Article
Affiliation country: