Studies on Kinetics, Isotherms, Thermodynamics and Adsorption Mechanism of Methylene Blue by N and S Co-Doped Porous Carbon Spheres
| Autor: | Yang Zhao, Yongpeng Ren, Ma Lulu, Feng Chen, Kunming Pan, Shizhong Wei |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2021 |
| Předmět: |
Langmuir
General Chemical Engineering Heteroatom Thermodynamics chemistry.chemical_element mechanism 02 engineering and technology 010402 general chemistry 01 natural sciences Endothermic process Isothermal process Article Catalysis porous carbon spheres symbols.namesake Adsorption General Materials Science QD1-999 Chemistry 021001 nanoscience & nanotechnology 0104 chemical sciences adsorption heteroatom-doping symbols methylene blue van der Waals force 0210 nano-technology Carbon |
| Zdroj: | Nanomaterials Volume 11 Issue 7 Nanomaterials, Vol 11, Iss 1819, p 1819 (2021) |
| ISSN: | 2079-4991 |
| DOI: | 10.3390/nano11071819 |
| Popis: | 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 m2 g−1, 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 R2 (0.9999). The Langmuir isothermal adsorption equation fitted well with the experimental results with an R2 value of 0.9618, and the MB maximum adsorption quantity was 909.10 mg g−1. 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. |
| Databáze: | OpenAIRE |
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