In:
Colloids and Interfaces, MDPI AG, Vol. 2, No. 2 ( 2018-05-06), p. 19-
Abstract:
An efficient process was developed allowing the removal of metal ions from polycontaminated aqueous solutions by combining modified colloids and membranes. Firstly, filtration experiments were performed using polyethersulfone membranes modified by a self-assembled multilayer film of polyelectrolytes. These polymer-modified membranes allowed the uptake of more than 90% of the metal ions initially present in the contaminated solutions (for solutions concentrated at 50 mg L−1). Secondly, adsorption experiments were carried out with colloidal silica encapsulated with carboxymethyl chitosan (SiO2-CMCS) or with mesoporous silica functionalized by grafting of 1,4,8,11-tetraazacyclotetradecane, i.e., cyclam (SiO2-cyclam). The adsorption capacity of these compounds was shown to be higher than numerous other literature-known adsorbents, reaching 68 and 61 mg g−1 towards Cu(II) for SiO2-CMCS and SiO2-cyclam, respectively. Finally, by coupling adsorption with ultrafiltration in the tangential mode, the removal of Cu(II), Ni(II) and Zn(II) ions was found to be improved, allowing to reach a removal efficiency of 99% towards Cu(II), Ni(II) and Zn(II) ions at a metal concentration of 50 mg L−1, and a promising removal efficiency around 70% at a very high metal concentration of 1200 mg L−1. The mechanisms involved in the capture of the metal ions by modified membranes and colloids are also discussed.
Type of Medium:
Online Resource
ISSN:
2504-5377
DOI:
10.3390/colloids2020019
Language:
English
Publisher:
MDPI AG
Publication Date:
2018
detail.hit.zdb_id:
2934567-4
