Studies on Kinetics, Isotherms, Thermodynamics and Adsorption Mechanism of Methylene Blue by N and S Co-Doped Porous Carbon Spheres
Heteroatom-doped carbon is widely used in the fields of adsorbents, electrode materials and catalysts due to its excellent physicochemical properties. N and S co-doped porous carbon spheres (N,S-PCSs) were synthesized using glucose and L-cysteine as carbon and heteroatom sources using a combined hyd...
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MDPI AG
2021-07-01
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| Series: | Nanomaterials |
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| Online Access: | https://www.mdpi.com/2079-4991/11/7/1819 |
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| author | Yongpeng Ren Feng Chen Kunming Pan Yang Zhao Lulu Ma Shizhong Wei |
| author_facet | Yongpeng Ren Feng Chen Kunming Pan Yang Zhao Lulu Ma Shizhong Wei |
| author_sort | Yongpeng Ren |
| collection | DOAJ |
| description | Heteroatom-doped carbon is widely used in the fields of adsorbents, electrode materials and catalysts due to its excellent physicochemical properties. N and S co-doped porous carbon spheres (N,S-PCSs) were synthesized using glucose and L-cysteine as carbon and heteroatom sources using a combined hydrothermal and KOH activation process. The physicochemical structures and single-factor methylene blue (MB) adsorption properties of the N,S-PCSs were then studied. The optimized N,S-PCSs-1 possessed a perfect spherical morphology with a 2–8-μm diameter and a large specific area of 1769.41 m<sup>2</sup> g<sup>−</sup><sup>1</sup>, in which the N and S contents were 2.97 at% and 0.88 at%, respectively. In the single-factor adsorption experiment for MB, the MB adsorption rate increased with an increase in carbon dosage and MB initial concentration, and the adsorption reached equilibrium within 2–3 h. The pseudo-second-order kinetic model could excellently fit the experimental data with a high R<sup>2</sup> (0.9999). The Langmuir isothermal adsorption equation fitted well with the experimental results with an R<sup>2</sup> value of 0.9618, and the MB maximum adsorption quantity was 909.10 mg g<sup>−</sup><sup>1</sup>. The adsorption of MB by N,S-PCSs-1 was a spontaneous, endothermic, and random process based on the thermodynamics analyses. The adsorption mechanism mainly involved Van der Waals force adsorption, π-π stacking, hydrogen bonds and Lewis acid–base interactions. |
| first_indexed | 2024-03-10T09:30:05Z |
| format | Article |
| id | doaj.art-fde27513d0b7436e96b23c1aa0967593 |
| institution | Directory Open Access Journal |
| issn | 2079-4991 |
| language | English |
| last_indexed | 2024-03-10T09:30:05Z |
| publishDate | 2021-07-01 |
| publisher | MDPI AG |
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| series | Nanomaterials |
| spelling | doaj.art-fde27513d0b7436e96b23c1aa09675932023-11-22T04:34:24ZengMDPI AGNanomaterials2079-49912021-07-01117181910.3390/nano11071819Studies on Kinetics, Isotherms, Thermodynamics and Adsorption Mechanism of Methylene Blue by N and S Co-Doped Porous Carbon SpheresYongpeng Ren0Feng Chen1Kunming Pan2Yang Zhao3Lulu Ma4Shizhong Wei5School of Materials Science and Engineering, Henan University of Science and Technology, Luoyang 471003, ChinaSchool of Environmental and Biological Engineering, Henan University of Engineering, Zhengzhou 451191, ChinaSchool of Materials Science and Engineering, Henan University of Science and Technology, Luoyang 471003, ChinaHenan Key Laboratory of High-Temperature Structural and Functional Materials, National Joint Engineering Research Center for Abrasion Control and Molding of Metal Materials, Henan University of Science and Technology, Luoyang 471003, ChinaSchool of Environmental and Biological Engineering, Henan University of Engineering, Zhengzhou 451191, ChinaSchool of Materials Science and Engineering, Henan University of Science and Technology, Luoyang 471003, ChinaHeteroatom-doped carbon is widely used in the fields of adsorbents, electrode materials and catalysts due to its excellent physicochemical properties. N and S co-doped porous carbon spheres (N,S-PCSs) were synthesized using glucose and L-cysteine as carbon and heteroatom sources using a combined hydrothermal and KOH activation process. The physicochemical structures and single-factor methylene blue (MB) adsorption properties of the N,S-PCSs were then studied. The optimized N,S-PCSs-1 possessed a perfect spherical morphology with a 2–8-μm diameter and a large specific area of 1769.41 m<sup>2</sup> g<sup>−</sup><sup>1</sup>, in which the N and S contents were 2.97 at% and 0.88 at%, respectively. In the single-factor adsorption experiment for MB, the MB adsorption rate increased with an increase in carbon dosage and MB initial concentration, and the adsorption reached equilibrium within 2–3 h. The pseudo-second-order kinetic model could excellently fit the experimental data with a high R<sup>2</sup> (0.9999). The Langmuir isothermal adsorption equation fitted well with the experimental results with an R<sup>2</sup> value of 0.9618, and the MB maximum adsorption quantity was 909.10 mg g<sup>−</sup><sup>1</sup>. The adsorption of MB by N,S-PCSs-1 was a spontaneous, endothermic, and random process based on the thermodynamics analyses. The adsorption mechanism mainly involved Van der Waals force adsorption, π-π stacking, hydrogen bonds and Lewis acid–base interactions.https://www.mdpi.com/2079-4991/11/7/1819methylene blueporous carbon spheresheteroatom-dopingadsorptionmechanism |
| spellingShingle | Yongpeng Ren Feng Chen Kunming Pan Yang Zhao Lulu Ma Shizhong Wei Studies on Kinetics, Isotherms, Thermodynamics and Adsorption Mechanism of Methylene Blue by N and S Co-Doped Porous Carbon Spheres Nanomaterials methylene blue porous carbon spheres heteroatom-doping adsorption mechanism |
| title | Studies on Kinetics, Isotherms, Thermodynamics and Adsorption Mechanism of Methylene Blue by N and S Co-Doped Porous Carbon Spheres |
| title_full | Studies on Kinetics, Isotherms, Thermodynamics and Adsorption Mechanism of Methylene Blue by N and S Co-Doped Porous Carbon Spheres |
| title_fullStr | Studies on Kinetics, Isotherms, Thermodynamics and Adsorption Mechanism of Methylene Blue by N and S Co-Doped Porous Carbon Spheres |
| title_full_unstemmed | Studies on Kinetics, Isotherms, Thermodynamics and Adsorption Mechanism of Methylene Blue by N and S Co-Doped Porous Carbon Spheres |
| title_short | Studies on Kinetics, Isotherms, Thermodynamics and Adsorption Mechanism of Methylene Blue by N and S Co-Doped Porous Carbon Spheres |
| title_sort | studies on kinetics isotherms thermodynamics and adsorption mechanism of methylene blue by n and s co doped porous carbon spheres |
| topic | methylene blue porous carbon spheres heteroatom-doping adsorption mechanism |
| url | https://www.mdpi.com/2079-4991/11/7/1819 |
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