Chiang Hung-Lung, Chiang P C, Huang C P
Department of Environmental Engineering, Fooyin Institute Technology, Kaoshiung Hsien, Taiwan, ROC.
Chemosphere. 2002 Apr;47(3):267-75.
Ozonation can modify the surface property of an activated carbon such as specific surface area, pore volume, and functional group. Results indicate that ozonation can increase the specific surface area of an activated carbon from 783+/-51 to 851+/-25 m2/g due in part to increasing micropores (those below 15 A). However, there is no change in macropore and mesopore upon ozonation. The amount of oxygen functional group (OFG) increases from 197+/-4 to 240+/-4 microeq/g, mostly in hydroxyl and carboxyl groups upon ozone treatment. These oxygen-containing functional groups are stable in the temperature range 30-250 degrees C, but begin to decompose when temperature increases beyond 300 and 350 degrees C. When the temperature reaches 1200 degrees C, all OFGs virtually disappear. The effect of ozone treatment on the adsorption of volatile organic carbon (VOC) was exemplified by methylethylketone (MEK) and benzene. The adsorption density of MEK and benzene by ozone treated activated carbon (AC(O3)) are greater than that by the untreated (AC), with MEK being more adsorbable than benzene. Results of factorial analysis indicate that physical characteristics, namely, micropore, BET surface area, pore diameter (PD), micropore volume (MV) play an important role on benzene and MEK adsorption.
臭氧化可以改变活性炭的表面性质，如比表面积、孔体积和官能团。结果表明，臭氧化可使活性炭的比表面积从783±51增加到851±25 m²/g，部分原因是微孔（小于15 Å的孔）增加。然而，臭氧化后大孔和中孔没有变化。臭氧处理后，氧官能团（OFG）的量从197±4增加到240±4微当量/克，主要是羟基和羧基。这些含氧官能团在30 - 250℃的温度范围内稳定，但当温度超过300和350℃时开始分解。当温度达到1200℃时，所有的OFG实际上都消失了。以甲基乙基酮（MEK）和苯为例，说明了臭氧处理对挥发性有机碳（VOC）吸附的影响。臭氧处理的活性炭（AC(O3)）对MEK和苯的吸附密度大于未处理的活性炭（AC），MEK比苯更易吸附。因子分析结果表明，物理特性，即微孔、BET表面积、孔径（PD）、微孔体积（MV）对苯和MEK的吸附起着重要作用。
