全组分木质活性炭球的制备及其乙烯吸附性能研究

目的 制备全组分木质活性炭球，应用于乙烯吸附，筛选出乙烯吸附效果最好的活性炭球制备工艺。方法 以木材液化物为原料，探究不同的固化时间对制备的全组分木质活性炭球微观形貌的影响，利用场发射扫描电子显微镜观察其微观结构，通过氮气吸附-解析等温线计算样品孔径分布及其比表面积;使用气相色谱仪，结合乙烯吸附标准曲线，分析时间及吸附剂用量对4种活性炭球吸附乙烯性能的影响。结果 随着固化时间的增加，碳球表面趋于光滑、内部结构越来越致密，石墨化程度逐渐提高，比表面积和孔容逐渐减小。当固化时间为0.5 h时，比表面积高达2 073 m²/g，乙烯吸附量高达197.99 mg/g，约3 h达到吸附平衡。结论 全组分木质活性炭球能有效吸附乙烯气体，固化时间太长，活性炭球内部孔隙减少，不利于吸附乙烯气体。活性炭球孔容越大，乙烯吸附效果越好。

Preparation and Ethylene Adsorption Performance of Full-component Wood-based Activated Carbon Spheres

The work aims to preparefull-component wood-based activated carbon spheres (FWACs), apply them to ethylene adsorption and select an activated carbon sphere preparation process with the best ethylene adsorption effect. With liquefied wood as raw materials, the effect of different curing time on the full-component wood-based activated carbon spheres was explored. Its microstructure was observed with a field emission scanning electron microscope, and the pore size distribution and specific surface area of the sample were calculated according to the nitrogen adsorption-desorption isotherm. The effects of time and adsorbent dosage on the ethylene adsorption performance of four kinds of activated carbon spheres were analyzed with a gas chromatograph in combination with ethylene adsorption standard curves. The results indicated that the carbon sphere surface became smooth, the internal structure became dense and the degree of graphitization increased with the increase of curing time; while the specific surface area and pore volume decreased. When the curing time was 0.5 h, the specific surface area was up to 2 073 m2/g, and the adsorption effect of ethylene was 197.99 mg/g. It took 3 hours to reach adsorption equilibrium. All-component wood-based activated carbon spheres can effectively adsorb ethylene gas, but its curing time is too long, and the internal pores of activated carbon spheres are reduced, which is not conducive to the adsorption of ethylene gas. The larger the pore volume of activated carbon spheres, the better the ethylene adsorption effect.