Chiang Yu-Chun, Chen Yu-Jen, Wu Cheng-Yen
Department of Mechanical Engineering, Yuan Ze University, Taoyuan 32003, Taiwan.
Fuel Cell Center, Yuan Ze University, Taoyuan 32003, Taiwan.
Materials (Basel). 2017 Nov 11;10(11):1296. doi: 10.3390/ma10111296.
Microporous activated carbon fibers (ACFs) were developed for CO₂ capture based on potassium hydroxide (KOH) activation and tetraethylenepentamine (TEPA) amination. The material properties of the modified ACFs were characterized using several techniques. The adsorption breakthrough curves of CO₂ were measured and the effect of relative humidity in the carrier gas was determined. The KOH activation at high temperature generated additional pore networks and the intercalation of metallic K into the carbon matrix, leading to the production of mesopore and micropore volumes and providing access to the active sites in the micropores. However, this treatment also resulted in the loss of nitrogen functionalities. The TEPA amination has successfully introduced nitrogen functionalities onto the fiber surface, but its long-chain structure blocked parts of the micropores and, thus, made the available surface area and pore volume limited. Introduction of the power of time into the Wheeler equation was required to fit the data well. The relative humidity within the studied range had almost no effects on the breakthrough curves. It was expected that the concentration of CO₂ was high enough so that the impact on CO₂ adsorption capacity lessened due to increased relative humidity.
基于氢氧化钾（KOH）活化和四乙烯五胺（TEPA）胺化开发了用于二氧化碳捕集的微孔活性炭纤维（ACF）。使用多种技术对改性ACF的材料性能进行了表征。测量了二氧化碳的吸附穿透曲线，并确定了载气中相对湿度的影响。高温下的KOH活化产生了额外的孔网络，金属钾嵌入碳基体，导致中孔和微孔体积的产生，并提供了进入微孔中活性位点的通道。然而，这种处理也导致了氮官能团的损失。TEPA胺化成功地在纤维表面引入了氮官能团，但其长链结构阻塞了部分微孔，因此使有效表面积和孔体积受到限制。需要将时间幂引入惠勒方程才能很好地拟合数据。在所研究的范围内，相对湿度对穿透曲线几乎没有影响。预计二氧化碳浓度足够高，因此相对湿度增加对二氧化碳吸附容量的影响会减小。
