Adsorption of Basic Dyes Using Walnut Shell-based Biochar Produced by Hydrothermal Carbonization
Chunli Kang , Ling Zhu , Yixue Wang , Yuhan Wang , Kunkun Xiao , Tao Tian
Chemical Research in Chinese Universities ›› 2018, Vol. 34 ›› Issue (4) : 622 -627.
Adsorption of Basic Dyes Using Walnut Shell-based Biochar Produced by Hydrothermal Carbonization
Hydrothermal carbon(HC) was prepared from walnut shells, which are abundant in Northeastern China. The prepared HC was used as a precursor to produce nitric acid modified carbon(MC). The hydrothermal carbonization included dehydration and decarboxylation processes wherein the hemicellulose was completely decomposed and the cellulose was partly decomposed, with some oxygen-containing functional groups being produced. The aromaticity, specific surface area and pore content of the HC increased, but its polarity decreased. With 6 mol/L nitric acid and a modification time of 15 min, the specific surface area and pore content decreased, but the proportion of oxygen-containing functional groups on the surface increased significantly, thereby improving the dye adsorption performance. The adsorption of methylene blue and malachite green was best described by the pseudo-second-order kinetic and Langmuir isotherm models. The adsorption capacity of MC was determined to be much larger than that of HC.
Biochar / Adsorption / Walnut shell / Hydrothermal carbonization / Basic dye
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| [2] |
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| [3] |
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| [4] |
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| [5] |
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| [6] |
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| [7] |
|
| [8] |
|
| [9] |
|
| [10] |
|
| [11] |
|
| [12] |
|
| [13] |
|
| [14] |
|
| [15] |
|
| [16] |
|
| [17] |
|
| [18] |
|
| [19] |
|
| [20] |
|
| [21] |
|
| [22] |
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| [23] |
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