Synthesis of WS42- Intercalated NiZnAl LDHs as Effective Adsorbents to Remove Copper Ions from Water
A series of WS42- intercalated NiZnAl ternary-layered double-hydroxides (LDHs) with various Ni/Zn ratios were synthesized by an ion-exchange method and used as adsorbents to remove Cu2+ from water. The introduction of Zn produced ZnS on the surface of LDHs. The LDH with the Ni/Zn/Al molar ratio of 0...
| Publié dans: | Langmuir : the ACS journal of surfaces and colloids. - 1985. - 40(2024), 11 vom: 19. März, Seite 5701-5714 |
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| Auteur principal: | |
| Autres auteurs: | , , , |
| Format: | Article en ligne |
| Langue: | English |
| Publié: |
2024
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| Accès à la collection: | Langmuir : the ACS journal of surfaces and colloids |
| Sujets: | Journal Article |
| Résumé: | A series of WS42- intercalated NiZnAl ternary-layered double-hydroxides (LDHs) with various Ni/Zn ratios were synthesized by an ion-exchange method and used as adsorbents to remove Cu2+ from water. The introduction of Zn produced ZnS on the surface of LDHs. The LDH with the Ni/Zn/Al molar ratio of 0.1/1.9/1 showed the best adsorption ability. Cu2+ ions are removed via three routes: forming [Cu-WS4]n- complexes via soft acid-soft base interaction between WS42- and Cu2+, isomorphic substitution of Zn2+ in sheets by Cu2+, and cation exchange of Cu2+, with ZnS on the surface of LDHs. With the increased Cu2+ concentration, the complexes dominated the adsorption because polynuclear [Cu-WS4]n- complexes with high Cu/W ratios (2-6) may be formed. Cu+ is present in such complexes, which is produced by the internal redox. Even at Cu2+ concentration up to 600 mg·L-1, neither amorphous CuWS4 nor decreased interlayer distance was observed. Contrarily, the interlayer distance was slightly enlarged due to forming bigger [Cu-WS4]n- complexes. The adsorption followed the pseudo-second-order kinetics and Langmuir isotherm model. The experimental maximum adsorption capacity reached 555.4 mg·g-1 |
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| Description: | Date Revised 19.03.2024 published: Print-Electronic Citation Status PubMed-not-MEDLINE |
| ISSN: | 1520-5827 |
| DOI: | 10.1021/acs.langmuir.3c03347 |