不同结构活性炭对甲苯的吸附性能

考察了不同结构的活性炭样品对高浓度和低浓度甲苯蒸汽的吸附行为,采用低温(77 K)氮气吸附和129Xe-核磁共振方法对所用活性炭的结构进行了表征.并将活性炭对甲苯的吸附性能与其结构进行了关联.结果表明孔容积大的活性炭对高浓度甲苯蒸汽吸附容量大,而具有丰富微孔和较小平均孔径的活性炭对低浓度(2×10-5)甲苯蒸汽具有高的吸附容量.沥青基活性炭纤维对低浓度(2×10-5)甲苯蒸汽表现出较好的吸附能力.随着比表面积的增大,活性炭纤维对低浓度(2×10-5)甲苯蒸汽的吸附容量略有增加.OG5A,OG10A,OG15A和OG20A在30 ℃下对2×10-5甲苯蒸汽的饱和吸附容量分别为202 mg/g,219 mg/g,221 mg/g和235 mg/g.

Toluene adsorption on various activated carbons with different pore structures

The toluene adsorption behavior of various activated carbons with different surface areas and pore structures was investigated by a static method at saturation concentration and a dynamic method at low concentration. The pore structures of these activated carbons were characterized by nitrogen adsorption at 77 K and 129Xe-NMR measurements. Results showed that activated carbons with a larger pore volume have the higher toluene adsorption capacity at saturation concentration. But at low concentration, activated carbons with abundant micropores and a narrow pore size have a higher adsorption capacity. Among the investigated samples, pitch-based activated carbon fibers (ACFs) showed a better toluene adsorption capacity at low concentration (2×10-5). With the increase of surface area for ACFs, the toluene adsorption capacities at low concentration (2×10-5) increase slightly and for OG5A, OG10A, OG15A and OG20A at 30 ℃ were 202 mg/g, 219 mg/g, 221 mg/g and 235 mg/g respectively.