Abstract
In this study, the effect of an acidic treatment on granular activated carbon (GAC) and activated carbon fibers (ACF) was investigated for a $Pb^{2+}$ and $Ni^{2+}$ ion adsorption. 1.0 M nitric acid solution was used as the acid solution for the surface treatment. Surface properties of the GAC and ACF were characterized by the pH, elemental analysis and pHpzc (pH of the point of zero charge). Their specific surface area and the pore structure were also evaluated by the nitrogen adsorption data at 77K. As a result, the acidic treatment led to an increase of the oxygen-containing functional groups. Furthermore, the adsorption capacity of the acid-treated GAC and ACF was improved in the order of acidic-ACF > untreated-ACF > acidic-GAC > untreated-GAC, though the decrease in specific surface area induced by a pore blocking of the functional groups was observed.
본 연구에서는 산 표면 처리한 입상 활성탄(GAC)과 활성 탄소섬유(ACF)에 의한 $Pb^{2+}$와 $Ni^{2+}$ 이온의 흡착 특성을 고찰하였다. 산 표면 처리용액으로는 1.0 M 질산 용액을 사용하였다. GAC와 ACF의 표면특성분석은 pH, 등전점(pHpzc), 그리고 원소분석기를 사용하였으며, 비표면적과 기공구조는 77K에서 $N_2$ 등온흡착 방법으로 측정하였다. 본 실험결과 GAC 와 ACF를 산으로 표면 처리한 경우 산소를 포함한 작용기가 증가하였다. 이처럼 산 표면 처리에 의해 증가된 표면 작용기에 따른 GAC 및 ACF의 기공이 막힘에도 불구하고, acidic-ACF > untreated-ACF > acdic-GAC > untreated-GAC 순으로 중금속 흡착능이 증가하였다.
