{"database":"biostudies-literature","file_versions":[],"scores":null,"additional":{"omics_type":["Unknown"],"volume":["10(1)"],"submitter":["Jang EH"],"pubmed_abstract":["We report on the synthesis and characterization of highly monodisperse amorphous silica nanoparticles (ASNs) and mesoporous silica nanoparticles (MSNs) with particle sizes of 15-60 nm. We demonstrate adsorption of Cr(VI) ions on amino-functionalized ASNs (NH<sub>2</sub>-ASNs) and MSNs (NH<sub>2</sub>-MSNs) and their removal from aqueous environments and show the specific surface area (SSA) of NH<sub>2</sub>-MSNs is four times as larger as that of NH<sub>2</sub>-ASNs and that more than 70% of the total SSA of NH<sub>2</sub>-MSNs is due to the presence of nanopores. Analyses of Cr(VI) adsorption kinetics on NH<sub>2</sub>-ASNs and NH<sub>2</sub>-MSNs exhibited relatively rapid adsorption behavior following pseudo-second order kinetics as determined by nonlinear fitting. NH<sub>2</sub>-ASNs and NH<sub>2</sub>-MSNs exhibited significantly higher Cr(VI) adsorption capacities of 34.0 and 42.2 mg·g<sup>-1</sup> and removal efficiencies of 61.9 and 76.8% than those of unfunctionalized ASNs and MSNs, respectively. The Langmuir model resulted in best fits to the adsorption isotherms of NH<sub>2</sub>-ASNs and NH<sub>2</sub>-MSNs. The adsorption of Cr(VI) on NH<sub>2</sub>-ASNs and NH<sub>2</sub>-MSNs was an endothermic and spontaneous process according to the thermodynamic analyses of temperature-dependent adsorption isotherms. The removal efficiencies of NH<sub>2</sub>-ASNs and NH<sub>2</sub>-MSNs exhibited a moderate reduction of less than 25% of the maximum values after five regeneration cycles. Furthermore, NH<sub>2</sub>-MSNs were also found to reduce adsorbed Cr(VI) into less harmful Cr(III)."],"journal":["Scientific reports"],"pagination":["5558"],"full_dataset_link":["https://www.ebi.ac.uk/biostudies/studies/S-EPMC7101345"],"repository":["biostudies-literature"],"pubmed_title":["A systematic study of hexavalent chromium adsorption and removal from aqueous environments using chemically functionalized amorphous and mesoporous silica nanoparticles."],"pmcid":["PMC7101345"],"pubmed_authors":["Chung S","Jang EH","Pack SP","Kim I"],"additional_accession":[]},"is_claimable":false,"name":"A systematic study of hexavalent chromium adsorption and removal from aqueous environments using chemically functionalized amorphous and mesoporous silica nanoparticles.","description":"We report on the synthesis and characterization of highly monodisperse amorphous silica nanoparticles (ASNs) and mesoporous silica nanoparticles (MSNs) with particle sizes of 15-60 nm. We demonstrate adsorption of Cr(VI) ions on amino-functionalized ASNs (NH<sub>2</sub>-ASNs) and MSNs (NH<sub>2</sub>-MSNs) and their removal from aqueous environments and show the specific surface area (SSA) of NH<sub>2</sub>-MSNs is four times as larger as that of NH<sub>2</sub>-ASNs and that more than 70% of the total SSA of NH<sub>2</sub>-MSNs is due to the presence of nanopores. Analyses of Cr(VI) adsorption kinetics on NH<sub>2</sub>-ASNs and NH<sub>2</sub>-MSNs exhibited relatively rapid adsorption behavior following pseudo-second order kinetics as determined by nonlinear fitting. NH<sub>2</sub>-ASNs and NH<sub>2</sub>-MSNs exhibited significantly higher Cr(VI) adsorption capacities of 34.0 and 42.2 mg·g<sup>-1</sup> and removal efficiencies of 61.9 and 76.8% than those of unfunctionalized ASNs and MSNs, respectively. The Langmuir model resulted in best fits to the adsorption isotherms of NH<sub>2</sub>-ASNs and NH<sub>2</sub>-MSNs. The adsorption of Cr(VI) on NH<sub>2</sub>-ASNs and NH<sub>2</sub>-MSNs was an endothermic and spontaneous process according to the thermodynamic analyses of temperature-dependent adsorption isotherms. The removal efficiencies of NH<sub>2</sub>-ASNs and NH<sub>2</sub>-MSNs exhibited a moderate reduction of less than 25% of the maximum values after five regeneration cycles. Furthermore, NH<sub>2</sub>-MSNs were also found to reduce adsorbed Cr(VI) into less harmful Cr(III).","dates":{"release":"2020-01-01T00:00:00Z","publication":"2020 Mar","modification":"2026-07-15T16:33:20.359Z","creation":"2026-07-07T03:08:18.994Z"},"accession":"S-EPMC7101345","cross_references":{"pubmed":["32221311"],"doi":["10.1038/s41598-020-61505-1"]}}