真空浸渍碳沉积法调变活性炭的孔径结构

Research on the Pore-structure of Activated Carbon Modified With Vacuum-dipping and Carbon-deposition

研究了以洗油与煤焦油作堵孔剂的碳沉积法对太西无烟煤制活性炭的调孔作用。发现改性后活性炭的孔结构一定程度上都有向微孔集中分布的趋势,但总孔容与比表面积有所下降。特别当洗油与煤焦油配比为19∶1,浸渍时间为2 h,沥干后在氮气氛围中经常规炭化得到的改性活性炭,微孔所占比例显著提高,且孔容和比表面积都较高,是较理想的气相吸附剂。堵孔剂浸渍时间超过4 h,将会出现过堵孔现象,导致孔容大幅减小,影响活性炭的吸附性能。

Activated carbon （AC） was prepared from commercial Taixi anthracite AC by dipping with tile mixture of absorbent oil and coal tar, and then followed by carbon deposition in the presence of nitrogen. The iodine number and nitrogen adsorption isotherm of AC were measured. Effect of the dipping condition on the pore - structure was investigated. The results show that the microporosity of AC is increased, when its total volume and surface are both reduced slightly. Especially, when the dipping time is 2 hours and coal tar： absorbent oil is 1： 19, the microporosity of this AC is increased as well as total volume and SBET are both high. And this AC could be used as an ideal gas absorbent. If the AC is dipped beyond 4 hours, its pore will be jammed overly and adsorbent capacity also be weakened.