활성탄 재질별 신탄과 사용탄에서의 CTAC 처리유무에 따른 perchlorate 제거 특성을 조사한 결과, 활성탄 사용연수에 관계없이 석탄계 재질의 활성탄에서 perchlorate에 대해 가장 늦은 파과시점을 나타내었으며, CTAC를 처리한 경우 파과에 도달하는 BV는 31640, CTAC를 처리하지 않은 경우는 2301로 나타나 CTAC를 처리할 경우 13.7배정도 파과시점이 연장되는 것으로 나타났다. 또한, 야자계 및 목탄계의 경우 CTAC 처리시 각각 Bed Volume(BV) 18409 및 5753에 파과에 도달하였으나 CTAC를 처리하지 않은 경우는 BV 719 및 258에 파과에 도달하여 25.6배 및 20배정도 사용기간이 연장되었다. 3.1년 사용탄의 경우에도 CTAC를 처리한 활성탄이 처리하지 않은 활성탄에 비해 파과시점이 $5{sim}6.5$배정도 연장되는 것으로 나타났다. 활성탄 g당 perchlorate에 대한 최대 흡착량(Adsorption capacity)(X/M) 평가에서는 CTAC를 처리한 석탄계, 야자계 및 목탄계 신탄의 최대 흡착량(X/M)이 각각 8303.7, 4478.8 및 $1152.5{mu}g/g$으로 나타나 CTAC를 처리하지 않은 석탄계, 야자계 및 목탄계 신탄의 최대 흡착량(X/M) 768.2, 299 및 $99.2{mu}g/g$에 비해 10.8배, 15배 및 11.6배정도 최대 흡착량(X/M)이 증가하는 것으로 나타났다. CUR(Carbon usage rate)의 경우 석탄계 활성탄은 perchlorate의 제거를 위해 0.71g/일을 사용하지만 CTAC를 처리한 경우는 0.05g/일을 사용하는 것으로 나타났으며, 야자계나 목탄계 활성탄의 경우는 2.16 g/일 및 3.45g/일의 활성탄을 사용하여야만 제어가 가능하지만 CTAC를 처리한 경우는 야자계와 목탄계 각각 1일 0.08 g과 0.17 g을 사용하여도 제어가 가능한 것으로 나타났다. 활성탄의 흡착용량을 나타내는 k값의 경우 CTAC를 처리한 석탄계 활성탄이 1781.7로 CTAC를 처리하지 않은 활성탄의 307.2에 비해 월등히 높은 값을 나타내었으며, 야자계 및 목탄계 재질의 활성탄의 경우에도 CTAC를 처리한 경우가 각각 997.6과 461.9로 CTAC를 처리하지 않은 활성탄의 102.5와 94.2에 비의 월등히 높은 k값을 나타내어 CTAC를 처리한 활성탄에서 perchlorate에 대한 흡착용량이 월등히 향상되는 것으로 나타났다.
Three different virgin and used activated carbons made of each coal(Calgon), coconut(Samchully) and wood(Picabiol) based activated carbons, and the activated carbons with treated with cetyltrimethylammonium chloride(CTAC) were tested for an adsorption performance of perchlorate in a continuous adsorption column. Breakthrough behavior was investigated for the virgin coal-, coconut-, wood-based activated carbons and the activated carbons with pretreatment with CTAC. The breakthrough points of the virgin coal-, coconut- and wood-based activated carbons were observed as 288 bed volume(BV), 719 BV and 2301 BV respectively. And the breakthrough points of the virgin coal-, coconut- and wood-based activated carbons with treated with CTAC were 5753 BV, 18409 BV and 31640 BV respectively. By using pretreatment with CTAC for the virgin activated carbons, the breakthrough point could be extended up to 25 times approximately. The breakthrough behavior was also investigated for used activated carbons(3.1 years) with and without treated with CTAC. The reported results of breakthrough points of with treated with CTAC were 5 times higher than those of without pretreatment with CTAC. Adsorption capacity(X/D) of the virgin coal-, coconut- and wood- based activated carbons, and the activated carbons with pretreatment with CTAC was observed. The experimental results of adsorption capacity showed that coal- based activated carbon was highest$(768.2{mu}g/g)$, coconut- based activated carbon was intermediate$(299{mu}g/g)$ and wood- based activated carbon was lowest$(99.2{mu}g/g)$. And the adsorption capacity of the virgin coal-, coconut- and wood activated carbons with pretreatment with CTAC was shown as 8303.7, 4478.8 and $1152.5{mu}g/g$ respectively. Moreover, carbon usage rates(CURs) for the activated carbons had been also investigated. The results of CURs for the virgin coal-, coconut- and wood- based activated carbons were shown as 0.71g/day, 2.16g/day and 3.45g/day respectively. and the virgin coal-, roconut- and wood- based activated carbons with pretreatment CTAC were shown as 0.05g/day, 0.08g/day and 0.17g/day respectively. The constant characteristic of the system, k values for coal-, coconut- and wood- based activated carbons were found to be 307.2, 102.5 and 94.2, respectively. And k values for coal-, coconut- and wood- based activated carbons with pretreatment CTAC were found to be 1781.7, 997.6 and 461.9 respectively Consequently, the results presented in this paper provided a better insight into the adsorption performance of perchlorate. This observation suggested that using the virgin activated carbon made of coal was the best selection for removal of percholrate in the water treatment for an advanced treatment. And when the activated carbons were treated with CTAC, higher removal efficiency for perchlorate in the water can be obtained.
