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Wang Z, Xu Z, Qiu D, Chu Y, Tang Y. Beneficial utilization of Al/Si/O-rich solid wastes for environment-oriented ceramic membranes. JOURNAL OF HAZARDOUS MATERIALS 2021; 401:123427. [PMID: 32763712 DOI: 10.1016/j.jhazmat.2020.123427] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 06/24/2020] [Accepted: 07/05/2020] [Indexed: 06/11/2023]
Abstract
Wide application of traditional multilayer ceramic membrane has been severely restricted by high costs associated with rare membrane materials and high sintering temperature. In this study, typical solid wastes (coal fly ash, river sediment and sewage sludge) were adopted as raw materials to provide an Al-Si-O matrix for single-layer ceramic membranes. Phase identification shows anorthite as major crystalline phase, while bulk density and pore characteristics of the membranes varied with different raw material compositions, with flexural strengths of 40.82-71.46 MPa, and average pore size of 0.23 μm, 0.28 μm, 0.32 μm and 0.84 μm. When the membranes were applied in an oily water treatment, the oil rejection reached >98 % when using any of the four membranes with oil/water emulsion permeate flux remaining at ∼1200 L/m2·h. Furthermore, the stability of ceramic membranes in harsh environmental conditions was confirmed, with negligible weight loss ratios after being corroded in acidic/alkalic media. In addition, more than 95 % of original flux can be achieved even after six cycles, which confirmed the excellent recyclability of the membranes. The successful fabrication and application of the environment-oriented single layer ceramic membranes from the Al-Si-O solid waste matrix provided a promising "waste-to-resource" strategy for beneficial utilization of typical solid wastes as ceramic raw materials.
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Affiliation(s)
- Ziyi Wang
- Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, PR China; State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, PR China
| | - Zhe Xu
- Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, PR China; State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, PR China
| | - Dong Qiu
- Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, PR China; State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, PR China
| | - Yaozhu Chu
- Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, PR China; State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, PR China
| | - Yuanyuan Tang
- Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, PR China; State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, PR China.
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Microstructural Investigation and On-Site Repair of Thin Pd-Ag Alloy Membranes. MEMBRANES 2020; 10:membranes10120384. [PMID: 33266176 PMCID: PMC7760571 DOI: 10.3390/membranes10120384] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 11/26/2020] [Accepted: 11/26/2020] [Indexed: 11/16/2022]
Abstract
Pd membranes act in an important role in H2 purification and H2 production in membrane reactors. Pd-Ag alloy membranes fabricated by consecutive electroless- and electroplating process on alumina tubes exhibited good stability under stringent heating/cooling cycles at a ramp rate of 10 K/min, imitating practical fast initiation or emergency shutdown conditions. Bilayer Pd-Ag membranes can form dense and uniform alloy after thermal treatment for 24 h at 823 K under H2 atmosphere, despite a porous structure due to the development of liquid-like properties above Tamman temperature to enforce the migrativity. On the contrary, alloying under N2 atmosphere resulted in a Pd-enriched layer. This led to a lower H2 flux but superior thermal stability compared to that alloying under H2 atmosphere. The trilayer approach of electroless-plated Pd, electro-polated Ag and electroless-plated Pd is not suitable to achieve homogeneous Pd-Ag alloys, which, on the other hand, presented the occurrence of a small gap between top Pd layer and middle Ag layer, probably due to insufficient wetting during plating process. An on-site repair treatment in analogous to MOCVD (Metal-organic Chemical Vapor Deposition) process was first proposed to extend the lifetime of Pd-Ag membrane, i.e., by vaporizing, and subsequent decomposition of Ag(OOCC2F5) powders to "preferentially" block the pinholes under vacuum and at working temperature of ca. 473-673 K, which effectively reduced the N2 flux by 57.4% compared to the initial value. The H2 flux, however, declined by 16.7% due to carbon deposition on the membrane surface, which requires further investigation. This approach shows some potential for on-site repair without disassembly or cooling to room temperature.
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Hydrogen production by steam methane reforming in membrane reactor equipped with Pd membrane deposited on NiO/YSZ/NiO multilayer-treated porous stainless steel. J Memb Sci 2018. [DOI: 10.1016/j.memsci.2018.05.037] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Synthesis and characterization of a silica-alumina composite membrane and its application in a membrane reactor. Sep Purif Technol 2018. [DOI: 10.1016/j.seppur.2017.12.021] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Confined and in-situ zeolite synthesis: A novel strategy for defect reparation over dense Pd membranes for hydrogen separation. Sep Purif Technol 2017. [DOI: 10.1016/j.seppur.2017.04.035] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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