A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
Adsorption characteristics of Cs+ on biogenic birnessite
Abstract Adsorption of Cs+ on biogenic birnessite was investigated and compared with (ad)sorption of other heavy metals and also with (ad)sorption on chemically synthesized birnessite. The adsorption density of Cs+ on biogenic birnessite was smaller than that on chemically synthesized birnessite; however, the (ad)sorption densities of Co2+ and Ni2+ on biogenic birnessite were larger than on chemically synthesized birnessite. These phenomena can be interpreted by considering the distinctive nano-structure of biogenic birnessite, which is not only poorly crystalline and includes organic matter but also according to EXAFS contains a greater proportion of vacant central metal sites than is found in synthetic birnessite. Adsorbed Cs+ ions on both birnessites were mainly in the form of outer sphere complexes, which cannot easily occupy vacant central metal sites in biogenic birnessite. Biogenic birnessite has a greater specific surface area and more fine pores than synthetic birnessite, but these factors do not necessarily lead to more adsorption sites for Cs+ ions.
Highlights Adsorption density of Cs+ on biogenic birnessite was smaller than synthetic one. Sorption density of Co2+ and Ni2+ was larger on biogenic birnessite than synthetic. Outer-sphere complex was observed on birnessite under high Cs concentrations. Interlayer Mn2+ contributed to sorption of metallic ions on biogenic birnessite.
Adsorption characteristics of Cs+ on biogenic birnessite
Abstract Adsorption of Cs+ on biogenic birnessite was investigated and compared with (ad)sorption of other heavy metals and also with (ad)sorption on chemically synthesized birnessite. The adsorption density of Cs+ on biogenic birnessite was smaller than that on chemically synthesized birnessite; however, the (ad)sorption densities of Co2+ and Ni2+ on biogenic birnessite were larger than on chemically synthesized birnessite. These phenomena can be interpreted by considering the distinctive nano-structure of biogenic birnessite, which is not only poorly crystalline and includes organic matter but also according to EXAFS contains a greater proportion of vacant central metal sites than is found in synthetic birnessite. Adsorbed Cs+ ions on both birnessites were mainly in the form of outer sphere complexes, which cannot easily occupy vacant central metal sites in biogenic birnessite. Biogenic birnessite has a greater specific surface area and more fine pores than synthetic birnessite, but these factors do not necessarily lead to more adsorption sites for Cs+ ions.
Highlights Adsorption density of Cs+ on biogenic birnessite was smaller than synthetic one. Sorption density of Co2+ and Ni2+ was larger on biogenic birnessite than synthetic. Outer-sphere complex was observed on birnessite under high Cs concentrations. Interlayer Mn2+ contributed to sorption of metallic ions on biogenic birnessite.
Adsorption characteristics of Cs+ on biogenic birnessite
Sasaki, Keiko (author) / Yu, Qianqian (author) / Momoki, Taichi (author) / Kaseyama, Takuya (author)
Applied Clay Science ; 101 ; 23-29
2014-06-21
7 pages
Article (Journal)
Electronic Resource
English
Adsorption characteristics of Cs+ on biogenic birnessite
| Online Contents | 2014
Molybdate adsorption by birnessite
| Elsevier | 2015
Molybdate adsorption by birnessite
| Online Contents | 2015
| British Library Online Contents | 2014
Sorption characteristics of lead cations on microporous organo-birnessite
| Online Contents | 2013