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Hydrochloric Acid Modification and Lead Removal Studies on Naturally Occurring Zeolites from Nevada, New Mexico, and Arizona. Processes (Basel) 2021. [DOI: 10.3390/pr9071238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Four naturally occurring zeolites were examined to verify their assignments as chabazites AZLB-Ca and AZLB-Na (Bowie, Arizona) and clinoptilolites NM-Ca (Winston, New Mexico) and NV-Na (Ash Meadows, Nevada). Based on powder X-ray diffraction, NM-Ca was discovered to be mostly quartz with some clinoptilolite residues. Treatment with concentrated HCl (12.1 M) acid resulted in AZLB-Ca and AZLB-Na, the chabazite-like species, becoming amorphous, as confirmed by powder X-ray diffraction. In contrast, NM-Ca and NV-Na, which are clinoptilolite-like species, withstood boiling in concentrated HCl acid. This treatment removes calcium, magnesium, sodium, potassium, aluminum, and iron atoms or ions from the framework while leaving the silicon framework intact as confirmed via X-ray fluorescence and diffraction. SEM images on calcined and HCl treated NV-Na were obtained. BET surface area analysis confirmed an increase in surface area for the two zeolites after treatment, NM-Ca 20.0(1) to 111(4) m2/g and NV-Na 19.0(4) to 158(7) m2/g. 29Si and 27Al MAS NMR were performed on the natural and treated NV-Na zeolite, and the data for the natural NV-Na zeolite suggested a Si:Al ratio of 4.33 similar to that determined by X-ray fluorescence of 4.55. Removal of lead ions from solution decreased from the native NM-Ca, 0.27(14), NV-Na, 1.50(17) meq/g compared to the modified zeolites, 30 min HCl treated NM-Ca 0.06(9) and NV-Na, 0.41(23) meq/g, and also decreased upon K+ ion pretreatment in the HCl modified zeolites.
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Kennedy DA, Mujčin M, Omar T, Tezel FH. Synthesis and preliminary gas permeation properties of vitreous composite clinoptilolite membranes. CHEM ENG COMMUN 2021. [DOI: 10.1080/00986445.2021.1903448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- D. A. Kennedy
- Department of Chemical and Biological Engineering, University of Ottawa, Ottawa, ON, Canada
| | - M. Mujčin
- Department of Chemical and Biological Engineering, University of Ottawa, Ottawa, ON, Canada
| | - T. Omar
- Department of Chemical and Biological Engineering, University of Ottawa, Ottawa, ON, Canada
| | - F. H. Tezel
- Department of Chemical and Biological Engineering, University of Ottawa, Ottawa, ON, Canada
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Alizadehgiashi M, Khuu N, Khabibullin A, Henry A, Tebbe M, Suzuki T, Kumacheva E. Nanocolloidal Hydrogel for Heavy Metal Scavenging. ACS NANO 2018; 12:8160-8168. [PMID: 29979568 DOI: 10.1021/acsnano.8b03202] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
We report a nanocolloidal hydrogel that combines the advantages of molecular hydrogels and nanoparticle-based scavengers of heavy metal ions. The hydrogel was formed by the chemical cross-linking of cellulose nanocrystals and graphene quantum dots. Over a range of hydrogel compositions, its structure was changed from lamellar to nanofibrillar, thus enabling the control of hydrogel permeability. Using a microfluidic approach, we generated nanocolloidal microgels and explored their scavenging capacity for Hg2+, Cu2+, Ni2+, and Ag+ ions. Due to the large surface area and abundance of ion-coordinating sites on the surface of nanoparticle building blocks, the microgels exhibited a high ion-sequestration capacity. The microgels were recyclable and were used in several ion scavenging cycles. These features, in addition to the sustainable nature of the nanoparticles, make this nanocolloidal hydrogel a promising ion-scavenging material.
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Affiliation(s)
- Moien Alizadehgiashi
- Department of Chemistry , University of Toronto , 80 Saint George Street , Toronto , Ontario M5S 3H6 , Canada
| | - Nancy Khuu
- Department of Chemistry , University of Toronto , 80 Saint George Street , Toronto , Ontario M5S 3H6 , Canada
| | - Amir Khabibullin
- Department of Chemistry , University of Toronto , 80 Saint George Street , Toronto , Ontario M5S 3H6 , Canada
| | - Andria Henry
- Department of Chemistry , University of Toronto , 80 Saint George Street , Toronto , Ontario M5S 3H6 , Canada
| | - Moritz Tebbe
- Department of Chemistry , University of Toronto , 80 Saint George Street , Toronto , Ontario M5S 3H6 , Canada
| | - Toyoko Suzuki
- Department of Chemistry , University of Toronto , 80 Saint George Street , Toronto , Ontario M5S 3H6 , Canada
- Graduate School of Engineering , Kobe University , Kobe 657-8501 , Japan
| | - Eugenia Kumacheva
- Department of Chemistry , University of Toronto , 80 Saint George Street , Toronto , Ontario M5S 3H6 , Canada
- Institute of Biomaterials and Biomedical Engineering , University of Toronto , 4 Taddle Creek Road , Toronto , Ontario M5S 3G9 , Canada
- Department of Chemical Engineering and Applied Chemistry , University of Toronto , 200 College Street , Toronto , Ontario M5S 3E5 , Canada
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