Sulfur-modified zeolite A as a low-cost strontium remover with improved selectivity for radioactive strontium.
Chemosphere
; 299: 134309, 2022 Jul.
Article
en En
| MEDLINE
| ID: mdl-35339528
ABSTRACT
Selective removal of radioactive strontium (90Sr) from the environment is important, and selective adsorption/ion exchange is appropriate for removal of trace amounts of 90Sr from large volumes of 90Sr-contaminated water. Although various inorganic ion-exchange materials, including zeolites, have been investigated intensively for removal of Sr2+ due to their excellent resistance to radiation and high ion-exchange capacity, their ion-exchange selectivity for Sr2+ is poor in the presence of competing ions such as Ca2+ and Mg2+. Here, sulfur-modified NaA zeolite (S-NaA) was prepared for low-cost, selective 90Sr removal because the elemental sulfur encapsulated in micropores provides additional Lewis acid-base interactions with Sr2+ during the Sr2+ ion-exchange. Our ion-exchange experiments revealed that S-NaA with 3 wt% sulfur (3 S-NaA) showed the highest Sr2+ selectivity among various S-NaAs containing up to 10 wt% sulfur because ion exchange involving bulky hydrated Sr2+ depends on the reduced micropore volume of S-NaA after sulfur loading. Most importantly, 3 S-NaA effectively and efficiently (>99.4%) removed 90Sr from groundwater containing 8.4 ppt 90Sr, demonstrating its excellent potential for practical application in the treatment of 90Sr-contaminated water.
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Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Estroncio
/
Zeolitas
Tipo de estudio:
Health_economic_evaluation
Idioma:
En
Año:
2022
Tipo del documento:
Article