Synthesis of alginate-polycation capsules of different composition: characterization and their adsorption for [As(iii)] and [As(v)] from aqueous solutions.
RSC Adv
; 10(48): 28755-28765, 2020 Aug 03.
Article
em En
| MEDLINE
| ID: mdl-35520048
ABSTRACT
The uptake of arsenite [As(iii)] and arsenate [As(v)] by functionalized calcium alginate (Ca-Alg) beads from aqueous solutions was investigated. Ca-Alg beads were protonated with poly-l-lysine (PLL) or polyethyleneimine (PEI) using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide/N-hydroxysuccinimide (EDC/NHS) or glutaraldehyde (GA) as crosslinking agents. Four types of protonated beads were prepared Ca-Alg-EDC/NHS (PLL or PEI) and Ca-Alg-GA (PLL or PEI). Fourier transform infrared spectroscopy in total attenuated reflection mode (FTIR-ATR), analysis showed presence and increased intensity of bands corresponding to OH, NH, CH2 and CH3 groups in modifications with both polycations. In addition, thermogravimetric analysis and atomic force microscopy of all modified capsules showed an increase in thermal stability and uniformity of the capsules, respectively. Ca-Alg-EDC/NHS-PLL beads had the maximum adsorption capacity of [As(v)] (312.9 ± 4.7 µg g-1 of the alginate) at pH 7.0 and 15 minute exposure, while Ca-Alg-EDC/NHS-PEI beads had the maximum adsorption capacity of [As(iii)] (1052.1 ± 4.6 µg g-1 of alginate). However, all these EDC containing beads were degraded in the presence of citrate. Ca-Alg-GA-PEI beads removed 252.8 ± 9.7 µg of [As(v)] µg g-1 of alginate and 524.7 ± 5.3 de [As(iii)] µg g-1 of alginate, resulting the most stable capsules and suitable for As removal.
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01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
RSC Adv
Ano de publicação:
2020
Tipo de documento:
Article