0 引言
1 实验
1.1 试剂与材料
1.2 中药渣活性炭的制备
1.3 结构、形貌及吸附性能表征
2 结果与讨论
2.1 微观形貌
Fig. 1 SEM (a, b) and TEM (c, d) images of HRC-5K-800图1 HRC-5K-800的SEM(a、b)图和TEM(c、d)图 |
Fig. 2 SEM images of activated carbon derived from herb residue: (a) PHRC; (b) HRC-2K-800; (c) HRC-3K-800;(d) HRC-4K-800; (e) HRC-5K-800; (f) HRC-6K-800; (g) HRC-5K-700; (h) HRC-5K-900图2 中药渣活性炭的SEM图:(a)PHRC;(b)HRC-2K-800;(c)HRC-3K-800;(d)HRC-4K-800;(e)HRC-5K-800;(f)HRC-6K-800;(g)HRC-5K-700;(h)HRC-5K-900 |
Fig. 3 TEM images of activated carbon derived from herb residue: (a) PHRC; (b) HRC-2K-800; (c) HRC-3K-800;(d) HRC-4K-800; (e) HRC-5K-800; (f) HRC-6K-800; (g) HRC-5K-700; (h) HRC-5K-900图3 中药渣活性炭的TEM图:(a)PHRC;(b)HRC-2K-800;(c)HRC-3K-800;(d)HRC-4K-800;(e)HRC-5K-800;(f)HRC-6K-800;(g)HRC-5K-700;(h)HRC-5K-900 |
2.2 结构特性
Fig. 4 N2 isothermal adsorption and desorption profiles (a, c) and corresponding pore size distribution (b, d) of PHRC-450 and HRC-nK-T图4 PHRC-450和HRC-nK-T的氮气等温吸脱附曲线(a、c)与孔径分布(b、d) |
Table 1 Textural properties of HRC表1 HRC的孔结构特性参数 |
吸附材料 | 比表面积/(m2/g) | 微孔比表面积/(m2/g) | 总孔容/(cm3/g) | 微孔孔容/(cm3/g) | (微孔孔容/总孔容)/% |
---|---|---|---|---|---|
PHRC-450 | 13 | 0 | 0.03 | 0.00 | 0.0 |
HRC-3K-500 | 1 419 | 1 216 | 0.64 | 0.49 | 76.6 |
HRC-3K-600 | 1 575 | 1 422 | 0.67 | 0.55 | 82.1 |
HRC-3K-700 | 3 018 | 2 081 | 1.47 | 0.90 | 61.2 |
HRC-3K-800 | 3 287 | 1 670 | 1.65 | 0.69 | 41.8 |
HRC-3K-900 | 3 183 | 1 003 | 1.73 | 0.38 | 22.0 |
HRC-2K-800 | 2 480 | 2 398 | 1.07 | 0.99 | 92.5 |
HRC-4K-800 | 3 414 | 3 160 | 1.84 | 1.58 | 85.9 |
HRC-5K-800 | 3 549 | 2 529 | 2.12 | 1.33 | 62.7 |
HRC-5K-700 | 2 839 | 2 267 | 1.60 | 1.13 | 70.6 |
HRC-5K-900 | 3 223 | 1 616 | 2.26 | 0.98 | 43.0 |
HRC-6K-800 | 3 772 | 3 179 | 2.04 | 1.11 | 54.0 |
Fig. 5 XRD patterns of HRC-nK-T图5 HRC-nK-T 的XRD衍射图 |
Fig. 6 XPS survey (a) and fitted spectra of C1s (b), O1s (c) and N1s (d) of HRC-5K-800图6 HRC-5K-800的XPS全谱(a)和C1s(b)、O1s(c)和N1s(d)的拟合图 |
Table 2 Surface C, N and O content in HRC-nK-T表2 HRC-nK-T中C、N和O的相对含量 |
吸附材料 | 相对含量/% | ||
---|---|---|---|
C | N | O | |
HRC-2K-800 | 79.55 | 1.00 | 19.45 |
HRC-3K-800 | 90.57 | 1.25 | 8.18 |
HRC-4K-800 | 83.74 | 1.22 | 15.04 |
HRC-5K-800 | 91.33 | 1.49 | 7.18 |
HRC-6K-800 | 91.22 | 1.39 | 7.39 |
HRC-5K-700 | 81.11 | 0.53 | 18.36 |
HRC-5K-900 | 87.80 | 0.47 | 11.73 |
Table 3 Relative contents of various bonding forms of C1s, N1s and O1s in HRC-nK-T表3 HRC-nK-T中C1s、N1s和O1s的各种成键形式的相对含量 |
吸附材料 | 成键形式相对含量/% | ||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
C1s | N1s | O1s | |||||||||||||||
C=C | C-C | C-O | C-N | C=O | COOH | N-C | 吡啶N | 吡咯N | 石墨化N | 氧化型N | O=C | O-C | HO-C | COOH | |||
HRC-2K-800 | 8.60 | 14.56 | 31.14 | 10.53 | 12.60 | 22.57 | 10.20 | 34.24 | 7.62 | 35.78 | 12.16 | 8.01 | 22.29 | 58.42 | 11.27 | ||
HRC-3K-800 | 12.57 | 29.70 | 21.76 | 10.18 | 3.72 | 22.07 | 7.84 | 25.34 | 30.77 | 14.49 | 21.56 | 6.69 | 31.43 | 38.44 | 23.44 | ||
HRC-4K-800 | 11.41 | 18.31 | 25.66 | 17.28 | 4.56 | 22.78 | 8.95 | 34.18 | 15.39 | 35.13 | 6.35 | 6.98 | 29.63 | 47.05 | 16.34 | ||
HRC-5K-800 | 4.15 | 20.37 | 34.94 | 13.26 | 5.04 | 22.25 | 0.00 | 29.96 | 48.61 | 5.09 | 16.34 | 20.19 | 30.61 | 31.08 | 18.12 | ||
HRC-6K-800 | 5.29 | 21.31 | 31.10 | 12.25 | 9.96 | 20.09 | 8.50 | 46.73 | 14.29 | 11.40 | 19.08 | 18.62 | 42.12 | 20.06 | 19.20 | ||
HRC-5K-700 | 7.92 | 31.78 | 28.37 | 10.44 | 5.86 | 15.62 | 0.00 | 47.75 | 41.13 | 8.06 | 6.06 | 31.60 | 19.90 | 37.31 | 11.19 | ||
HRC-5K-900 | 8.17 | 21.88 | 25.98 | 14.46 | 7.87 | 21.65 | 9.30 | 37.68 | 27.07 | 15.28 | 10.66 | 6.79 | 36.21 | 36.87 | 20.13 |
Fig. 7 FT-IR spectra of HRC-nK-800 (a) and HRC-5K-T (b)图7 HRC-nK-800(a)和HRC-5K-T(b)的FT-IR光谱 |
2.3 甲苯吸附
Fig. 8 Toluene isothermal adsorption curve (a) and isotherm model fitting results of toluene adsorption (b) by HRC-5K-800图8 HRC-5K-800的甲苯等温吸附曲线(a)和甲苯等温吸附拟合结果(b) |
Table 4 Toluene adsorption capacity of HRC-nK-T(P/P0 = 0-1, T = 25 ℃)表4 HRC-nK-T的甲苯吸附容量(P/P0 = 0 ~ 1,T = 25 ℃) |
吸附材料 | 甲苯吸附容量/(mg/g) |
---|---|
HRC-2K-800 | 859 |
HRC-3K-800 | 1 313 |
HRC-4K-800 | 1 316 |
HRC-5K-800 | 2 612 |
HRC-6K-800 | 818 |
HRC-5K-700 | 1 522 |
HRC-5K-900 | 2 186 |
Table 5 Comparison of toluene vapor adsorption of HRC-5K-800 with previous reported activated carbon表5 HRC-5K-800与已报道的活性炭的甲苯吸附对比结果 |
原材料 | 比表面积/(m2/g) | 掺杂原子 | 测试条件 | 吸附容量/(mg/g) | 数据来源 |
---|---|---|---|---|---|
药渣 | 3 549 | N, O | P/P0 = 0.9 ~ 1,T = 25 ℃ | 2 612 | 本文 |
豆渣 | 4 293 | / | P/P0 = 0.9 ~ 1,T = 25 ℃ | 1 587 | 文献[27] |
菜叶 | 1 651 | N, O | P = 3.8 kPa,T = 25 ℃ | 578 | 文献[41] |
谷壳 | 3 714 | / | 进口甲苯浓度 = 100 g/mL | 708 | 文献[42] |
软木 | 2 060 | / | P = 3 kPa,T = 25 ℃ | 720 | 文献[15] |
酒糟 | 763 | N | 进口甲苯浓度 = 600 g/mL | 438 | 文献[43] |
三聚氰胺脲醛树脂 | 2 784 | N, O | P = 3 kPa,T = 25 ℃ | 814 | 文献[12] |
榛子壳 | 2 360 | N, O | 流速 = 0.5 L/min,T = 25 ℃ | 896 | 文献[44] |
Table 6 Isotherm model fitting results of toluene adsorption by HRC-5K-800 (P/P0 = 0.9-1, T = 25 ºC)表6 HRC-5K-800的等温吸附曲线拟合结果(P/P0 = 0.9 ~ 1,T = 25 ℃) |
吸附材料 | Langmuir 模型 | Freundlich 模型 | ||||||
---|---|---|---|---|---|---|---|---|
qm/(mg/g) | k/(L/mg) | R2 | 标准误差 | KF/(mg1-1/n ∙L1/n ∙g-1) | n | R2 | 标准误差 | |
HRC-5K-800 | 65.49 | 0.84 | 0.991 2 | 22 | 30.49 | 1.43 | 0.990 1 | 0.7476 |