Facile preparation of N-doped activated carbon produced from rice husk for CO2 capture
Facile preparation of N-doped activated carbon produced from rice husk for CO2 capture
复制标题
轻松制备由稻壳生产的氮掺杂活性炭，用于捕获 CO(2)。
DOI：
10.1016/j.jcis.2020.08.021
复制
发表时间：
2021-01-15
影响因子：
9.9
通讯作者：
Yang, Xiaobing
中科院分区：
文献类型：
--
作者：
He, Song;Chen, Guanyu;Yang, Xiaobing
以稻壳为原料，通过炭化和KOH活化制备活性炭（AC）。研究了浸渍比和活化温度对AC性能的影响。在最佳条件下，AC的BET比表面积、总孔容和微孔容分别高达1495.52 m(2)/g、0.786 cm(3)/g和0.447 cm(3)/g。在KOH活化过程中同时进行以壳聚糖为氮源的表面修饰。 XPS 和 FT-IR 分析表明 N 物质已成功融入 AC 中。与AC-5（普通AC）相比，CAC-5（改性AC）表现出更好的CO2吸附性能，在273 K和1 bar下达到5.83 mmol/g，这可归因于N物种在AC表面形成亲CO2活性位点。研究了二氧化碳吸收量、特定尺寸截面内的微孔体积和氮含量之间的线性相关性。 CAC-5 的 CO2 吸附等量热（平均 30.21 kJ/mol）远高于 AC-5（平均 14.48 kJ/mol）。 Freundlich模型可以很好地描述CAC-5的吸附行为。 N 掺杂活性炭的高 IAST 选择性因子表明其对 CO2 的吸附选择性优于 N-2。 N掺杂活性炭对CO2的吸附过程同时存在物理吸附和化学吸附。 (C) 2020 Elsevier Inc. 保留所有权利。
Activated carbons (AC) were prepared by carbonization and KOH activation using rice husk as feedstock. The effects of impregnation ratios and activation temperatures on the properties of AC were investigated. Under optimum conditions, BET surface area, total pore volume and micropore volume of AC are as high as 1495.52 m(2)/g, 0.786 cm(3)/g and 0.447 cm(3)/g, respectively. Surface modification with chitosan as nitrogen source was performed simultaneously during KOH activation process. XPS and FT-IR analyses show that N-species was successfully incorporate into AC. Compared with AC-5 (general AC), CAC-5 (modified AC) exhibits better CO2 adsorption performance, reaching 5.83 mmol/g at 273 K and 1 bar, which can be attributed to the formation of the CO2-philic active sites on AC surface by N-species. The linear correlations between CO2 uptake, micropore volume within specific size section and N-content was investigated. The isosteric heat of CO2 adsorption for CAC-5 (average 30.21 kJ/mol) is much higher than that of AC-5 (average 14.48 kJ/mol). The adsorption behavior of CAC-5 can be well described by Freundlich model. The high IAST selectivity factor for N-doped ACs indicates their excellent adsorption selectivity for CO2 over N-2. Both physisorption and chemisorption are present in CO2 adsorption process of N-doped ACs. (C) 2020 Elsevier Inc. All rights reserved.