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Yan JY, Cao CY, Cao GP, Pan SF, Lv H, Saeed AMM. Mechanism of NCNTs Growth on Foamed Nickel and Thus-Prepared PS Hydrogenation High-Performance Carrier NCNTs@FN. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:6786-6805. [PMID: 38503426 DOI: 10.1021/acs.langmuir.3c03678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/21/2024]
Abstract
Traditional heterogeneous catalysts are affected in the catalytic hydrogenation of PS by the scale effect, viscosity effect, adhesion effect, and conformational effect, resulting in poor activity and stability. Monolithic Pd-CNTs@FN catalysts could eliminate or weaken the impact of these negative effects. We grew nitrogen-doped carbon nanotubes (NCNTs) on monolithic-foamed nickel (FN) and investigate their growth mechanism. Meanwhile, the feasibility of using the NCNTs@FN carrier for PS hydrogenation reaction was also verified. The growth of NCNTs on FN can be divided into 3 stages: initial growth stage, stable growth stage, and supersaturation stage. Finally, a three-layer structure of NCNT layer, dense carbon layer, and FN skeleton is formed. Two types of structures, nickel-doped carbon nanotubes (NiCNTs) and C-Ni alloy, are formed by combining C and Ni, while four nitrogen-doped structures, NPD, NPR, NG, and NO, are formed by C and N. The prepared carrier exhibited an extremely outstanding specific surface area (2.829 × 106 cm2/g) and strength (no NCNTs falling off after 24 h 500 rpm agitation), as well as high catalytic activity for PS hydrogenation after loaded with Pd (2.13 ± 0.95 nm), with a TOF of up to 27.6 gPS/(gPd•h). After 8 repetitions of the catalyst, there was no significant decrease in activity. This proves the excellent performance of Pd-NCNTs@FN in polymer hydrogenation reactions, laying a solid foundation for further research on the mechanism of NCNTs promoting PS hydrogenation and regulating the growth of NCNTs.
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Affiliation(s)
- Jun-Yang Yan
- UNILAB, State Key Laboratory of Chemical Engineering, School of Chemical Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Chun-Yan Cao
- UNILAB, State Key Laboratory of Chemical Engineering, School of Chemical Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Gui-Ping Cao
- UNILAB, State Key Laboratory of Chemical Engineering, School of Chemical Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Shao-Feng Pan
- UNILAB, State Key Laboratory of Chemical Engineering, School of Chemical Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Hui Lv
- UNILAB, State Key Laboratory of Chemical Engineering, School of Chemical Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Alaaddin M M Saeed
- UNILAB, State Key Laboratory of Chemical Engineering, School of Chemical Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
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Li N, Ying GG, Hong H, Deng WJ. Perfluoroalkyl substances in the urine and hair of preschool children, airborne particles in kindergartens, and drinking water in Hong Kong. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 270:116219. [PMID: 33401204 DOI: 10.1016/j.envpol.2020.116219] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2020] [Revised: 11/20/2020] [Accepted: 11/30/2020] [Indexed: 06/12/2023]
Abstract
Seven perfluorinated and polyfluorinated substances (PFASs), namely perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS), perfluoroheptanoic acid (PFHpA), perfluorohexanoic acid (PFHxA), and perfluoro-1,10-decanedicarboxylic acid (PFDDA), were evaluated in urine and hair samples from children (age: 4-6 years, N = 53), airborne particles sampled at 17 kindergartens, and tap water and bottled water samples. All samples were collected in Hong Kong. The analytical results suggested widespread PFAS contamination. All target PFASs were detected in at least 32% of urine samples, with geometric mean (GM) concentrations ranging from 0.18 to 2.97 ng/L, and in 100% of drinking water samples at GM concentrations of 0.18-21.1 ng/L. Although PFOS and PFDDA were not detected in hair or air samples, the other target PFASs were detected in 48-70% of hair samples (GM concentrations: 2.40-233 pg/g) and 100% of air samples (GM concentrations: 14.8-536.7 pg/m3). In summary, the highest PFAS concentrations were detected in airborne particles measured in kindergartens. PFOA was the major PFAS detected in hair, urine, and drinking water samples, while PFOA, PFDA, and PFHpA were dominant in airborne particles. Although a significant difference in PFAS concentrations in hair samples was observed between boys and girls (p < .05), no significant sex-related difference in urinary PFAS or paired PFAS (hair/urine) concentrations was observed.
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Affiliation(s)
- Na Li
- Department of Science and Environmental Studies, The Education University of Hong Kong, Tai Po, N.T., Hong Kong SAR, China; Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
| | - Guang-Guo Ying
- SCNU Environmental Research Institute, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou, 510006, China; School of Environment, South China Normal University, University Town, Guangzhou, 510006, China
| | - Huachang Hong
- College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua, 321004, China
| | - Wen-Jing Deng
- Department of Science and Environmental Studies, The Education University of Hong Kong, Tai Po, N.T., Hong Kong SAR, China; SCNU Environmental Research Institute, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou, 510006, China; School of Environment, South China Normal University, University Town, Guangzhou, 510006, China.
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A Functionalized Silicate Adsorbent and Exploration of Its Adsorption Mechanism. Molecules 2020; 25:molecules25081820. [PMID: 32316089 PMCID: PMC7221766 DOI: 10.3390/molecules25081820] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 04/04/2020] [Accepted: 04/14/2020] [Indexed: 12/15/2022] Open
Abstract
Active silicate materials have good adsorption and passivation effects on heavy metal pollutants. The experimental conditions for the preparation of active silicate heavy metal adsorbent (ASHMA) and the adsorption of Cu(II) by ASHMA were investigated. The optimum preparation conditions of ASHMA were as follows: 200 mesh quartz sand as the raw material, NaOH as an activating agent, NaOH/quartz sand = 0.45 (mass fraction), and calcination at 600 °C for 60 min. Under these conditions, the active silicon content of the adsorbent was 22.38% and the utilization efficiency of NaOH reached 89.11%. The adsorption mechanism of Cu(II) on the ASHMA was analyzed by the Langmuir and Freundlich isotherm models, which provided fits of 0.99 and 0.98, respectively. The separation coefficient (RL) and adsorption constant (n) showed that the adsorbent favored the adsorption of Cu(II), and the maximum adsorption capacity (Qmax) estimated by the Langmuir isotherm was higher than that of 300 mg/L. Furthermore, adsorption by ASHMA was a relatively rapid process, and adsorption equilibrium could be achieved in 1 min. The adsorbents were characterized by FT-IR and Raman spectroscopy. The results showed that the activating agent destroyed the crystal structure of the quartz sand under calcination, and formed Si-O-Na and Si-OH groups to realize activation. The experimental results revealed that the adsorption process involved the removal of Cu(II) by the formation of Si-O-Cu bonds on the surface of the adsorbent. The above results indicated that the adsorbent prepared from quartz sand had a good removal effect on Cu(II).
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Feng M, Lu H, Li CY, Cao GP. Carbon Nanotube Modified Ceramic Foams as Structured Palladium Supports for Polystyrene Hydrogenation. Ind Eng Chem Res 2019. [DOI: 10.1021/acs.iecr.9b01228] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Miao Feng
- UNILAB, State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Hui Lu
- UNILAB, State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Chen-Yang Li
- UNILAB, State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Gui-Ping Cao
- UNILAB, State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China
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Feng M, Luo ZH, Cao GP, Lu H. Tunable growth of carbon nanotubes forests on nickel foam as structured support for palladium catalyst toward polystyrene hydrogenation. J Taiwan Inst Chem Eng 2019. [DOI: 10.1016/j.jtice.2019.02.030] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Feng M, Luo ZH, Yi S, Lu H, Lu C, Li CY, Zhao JL, Cao GP. Palladium Supported on Carbon Nanotubes Decorated Nickel Foam as the Catalytic Stirrer in Heterogeneous Hydrogenation of Polystyrene. Ind Eng Chem Res 2018. [DOI: 10.1021/acs.iecr.8b03810] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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