1
|
Topnikova AP, Belokoneva EL, Volkov AS, Dimitrova OV, Stefanovich SY. Microporous framework polar silicate-germanates with a wide isomorphic substitution: (K 2.9Cs 0.1)(Sc 0.7In 0.3)[(Si 2.95Ge 0.05)O 9]·H 2O and (K 2.16Cs 0.84)Bi[(Si 1.5Ge 1.5)O 9]·H 2O. Z KRIST-CRYST MATER 2023. [DOI: 10.1515/zkri-2022-0056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/12/2023]
Abstract
Abstract
New silicate-germanates (K2.9Cs0.1)(Sc0.7In0.3)[(Si2.95Ge0.05)O9]·H2O and (K2.16Cs0.84)Bi[(Si0.5Ge0.5)3O9]·H2O have been synthesized in multi-component systems under mild hydrothermal conditions. The new compounds are classified as new representatives of close related K3ScSi3O9·H2O parent structure, sp. gr. Pmn21. Their structural and isomorphic peculiarities are compared with it as well as with earlier investigated K1.46Pb1.54Сa[(Ge0.23Si0.77)3O9](ОН)0.54·0.46Н2О. Together with other known compounds, silicate-germanates form the extensive family A3M[T3O9]·H2O, A = K, Cs, Ca, Pb; M = Ho, Sc, Lu, Tb, Er, Y, Bi, Pb, In; T = Si, Ge, with a mixed microporous framework combined of M-octahedra and T-tetrahedra. Large alkali metal or/and Ca, Pb cations fill broad framework channels with cross-section up to 7.3 Å. Because of wide isomorphic substitution in the channels, and in tetrahedra and octahedra, ion exchange properties in the family are expected. Due to polar symmetry, all the crystals possess second-order nonlinearity which was confirmed with positive SHG tests for four compositions. Powder SHG experiments demonstrated moderate second harmonic intensities of order of α-quartz standard signals.
Collapse
Affiliation(s)
- Anastasiia P. Topnikova
- Crystallography , Lomonosov Moscow State University, Faculty of Geology , Leninskie Gory 1 , Moscow 119991 , Russian Federation
| | - Elena L. Belokoneva
- Crystallography , Lomonosov Moscow State University, Faculty of Geology , Leninskie Gory 1 , Moscow 119991 , Russian Federation
| | - Anatoly S. Volkov
- Crystallography , Lomonosov Moscow State University, Faculty of Geology , Leninskie Gory 1 , Moscow 119991 , Russian Federation
| | - Olga V. Dimitrova
- Crystallography , Lomonosov Moscow State University, Faculty of Geology , Leninskie Gory 1 , Moscow 119991 , Russian Federation
| | - Sergey Yu. Stefanovich
- Crystallography , Lomonosov Moscow State University, Faculty of Geology , Leninskie Gory 1 , Moscow 119991 , Russian Federation
| |
Collapse
|
2
|
Fan X, Liu H, Anang E, Ren D. Effects of Electronegativity and Hydration Energy on the Selective Adsorption of Heavy Metal Ions by Synthetic NaX Zeolite. MATERIALS 2021; 14:ma14154066. [PMID: 34361261 PMCID: PMC8347618 DOI: 10.3390/ma14154066] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 07/11/2021] [Accepted: 07/17/2021] [Indexed: 12/03/2022]
Abstract
The adsorption capacity of synthetic NaX zeolite for Pb2+, Cd2+, Cu2+ and Zn2+ in single and multi-component systems were investigated. The effects of electronegativity and hydration energy on the selective adsorption, as well as potential selective adsorption mechanism of the NaX zeolite for Pb2+, Cd2+, Cu2+ and Zn2+ were also discussed. The maximum adsorption capacity order of the heavy metals in the single system was Pb2+ > Cd2+ > Cu2+ > Zn2+, and this could be related to their hydration energy and electronegativity. The values of the separation factors (α) and affinity constant (KEL) in different binary systems indicated that Pb2+ was preferentially adsorbed, and Zn2+ presented the lowest affinity for NaX zeolite. The selective adsorption capacities of the metals were in the order, Pb2+ > Cd2+ ≈ Cu2+ > Zn2+. The trend for the selective adsorption of NaX zeolite in ternary and quaternary systems was consistent with that in the binary systems. Pb2+ and Cu2+ reduced the stability of the Si-O-Al bonds and the double six-membered rings in the NaX framework, due to the high electronegativity of Pb2+ and Cu2+ than that of Al3+. The selective adsorption mechanism of NaX zeolite for the high electronegative metal ions could mainly result from the negatively charged O in the Si-O-Al structure of the NaX zeolite, hence heavy metal ions with high electronegativity display a strong affinity for the electron cloud of the oxygen atoms in the Si-O-Al. This study could evaluate the application and efficiency of zeolite in separating and recovering certain metal ions from industrial wastewater.
Collapse
Affiliation(s)
- Xianyuan Fan
- Department of Resource and Environmental Engineering, Wuhan University of Science and Technology, Wuhan 430081, China; (X.F.); (E.A.); (D.R.)
- Hubei Key Laboratory for Efficient Utilization and Agglomeration of Metallurgic Mineral Resources, Wuhan University of Science and Technology, Wuhan 430081, China
| | - Hong Liu
- Department of Resource and Environmental Engineering, Wuhan University of Science and Technology, Wuhan 430081, China; (X.F.); (E.A.); (D.R.)
- Hubei Key Laboratory for Efficient Utilization and Agglomeration of Metallurgic Mineral Resources, Wuhan University of Science and Technology, Wuhan 430081, China
- Correspondence: ; Tel.: +86-139-7148-8669
| | - Emmanuella Anang
- Department of Resource and Environmental Engineering, Wuhan University of Science and Technology, Wuhan 430081, China; (X.F.); (E.A.); (D.R.)
| | - Dajun Ren
- Department of Resource and Environmental Engineering, Wuhan University of Science and Technology, Wuhan 430081, China; (X.F.); (E.A.); (D.R.)
- Hubei Key Laboratory for Efficient Utilization and Agglomeration of Metallurgic Mineral Resources, Wuhan University of Science and Technology, Wuhan 430081, China
| |
Collapse
|
3
|
Lim WT, Seo SM, Lee OS, Wang L, Lu GQ. Synthesis and crystal structure of dehydrated, deaminated, and dealuminated zeolite Y (FAU): single-crystal structure of |Na33H26(Al5O4)|[Si126Al66O384]-FAU. J INCL PHENOM MACRO 2009. [DOI: 10.1007/s10847-009-9706-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
4
|
Zhen S, Seff K. Crystallographic Study of the Reaction of Zinc Vapor with Fully Cd2+-Exchanged Zeolite X. Complete Reduction of Cd2+ by Zn, Extraction of SiO44- and AlO45- from the Zeolite Framework, and Reduction of Si4+ to Si. J Phys Chem B 2000. [DOI: 10.1021/jp000886t] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Shenyan Zhen
- Department of Chemistry, University of Hawaii, 2545 The Mall, Honolulu, Hawaii 96822
| | - Karl Seff
- Department of Chemistry, University of Hawaii, 2545 The Mall, Honolulu, Hawaii 96822
| |
Collapse
|