Removal of antimonite and antimonate from water using Fe-based metal-organic frameworks: The relationship between framework structure and adsorption performance

We investigated the adsorption performance of five Fe-based MOFs(Fe-BTC,MIL-100(Fe),MIL-101(Fe),MIL-53(Fe)and MIL-88 C(Fe))for removal of antimonite(Sb(Ⅲ))and antimonate(Sb(Ⅴ))from water.Among these MOFs,MIL-101(Fe)exhibited the best adsorption capacities for both Sb(Ⅲ)and Sb(Ⅴ)(151.8 and 472.8 mg/g,respectively)which were higher than those of most adsorbents previously reported.The effect of steric hindrance was evident during Sb removal using the Fe-based MOFs,and the proper diameter of the smallest cage windows/channels should be considered an important parameter during the evaluation and selection of MOFs.Additionally,the adsorption capacities of MIL-101(Fe)for Sb(Ⅴ)decreased with increasing initial p H values(from 3.0 to 8.0),while the opposite trend was observed for Sb(Ⅲ).Chloride,nitrate and sulfate ions had a negligible influence on Sb(Ⅴ)adsorption,while NO3-and SO42-improved Sb(Ⅲ)adsorption.This result implies that inner sphere complexes might form during both Sb(Ⅲ)and Sb(Ⅴ)adsorption.

Antimony transformation and mobilization from stibnite by an antimonite oxidizing bacterium Bosea sp. AS-1

Soils and waters are heavily contaminated by antimony in Xikuangshan(XKS)mine area.It is widely accepted that oxidative dissolution of sulfide minerals and aqueous dissolution are the most prevalent geochemical mechanisms for the release of Sb to the environment.Bosea sp.AS-1 is an antimonite-oxidizer isolated from the mine slag in Xikuangshan Sb mine.Whole genome sequencing revealed the presence of multiple sulfur-oxidizing genes,antimony(Sb)metabolism genes and carbon fixation genes in AS-1 s genome.We therefore hypothesized that under oxic conditions,AS-1 could mediate the oxidation of sulfide and Sb(Ⅲ)in stibnite(Sb_(2)S_(3))and lead to the release of Sb.Indeed,strain AS-1 was discovered as an autotrophic Sb(Ⅲ)-oxidizer.Antimony mobilization studies conducted with strain AS-1showed significantly enhanced mobilization of Sb,and complete oxidation of released Sb and sulfur to Sb(V)and sulfate.In addition,AS-1 induced a faster release of Sb under heterotrophic condition,and new acicular minerals might form.These findings support the hypothesis that microorganisms play an important role in the mobilization and transformation of Sb in XKS mine area and may contribute to our further understanding of the Sb biogeochemical redox cycle in natural environment.

STUDIES ON THE CRYSTAL STRUCTURE OF TRISODIUM DIGALLO-(3,4)-ANTIMONITE (SODIUM ANTIMONO GALLATE)

Ⅰ. INTRODUCTIONSodium Antimono Gallate (Code name Sb-273) is a sort of oral antimonial anti-Japanese schistosomiasis medicine. Through clinical appraisal, Sb-273 was officially accepted as of low toxicity, and since 1970, has been in production for general use for treatment of schistosomiasis. It is synthesized by the Institute of Medicine of Nanjing and is a powder of cream colour. By recrystallizing it in water solution, we obtained a colourless and transparent monocrystal bulk. Element composition form of