碱改性活性炭对VOCs的吸附性能

选用3种经氢氧化钠改性的活性炭,研究了其对4种代表性VOCs(丁酮、乙酸乙酯、甲苯和四氯化碳)的吸附规律。结果表明:活性炭经碱改性后吸附性能有较大改善,吸附量的大小与其比表面积呈正相关性,而其比表面积多为微孔提供;改性活性炭对有机气体的吸附以物理吸附为主;吸附质的相对分子质量、密度、熔点与其在改性活性炭上的吸附量具有线性相关性,而沸点、饱和蒸气压、分子动力学直径则与吸附量无明显相关性;对于同一吸附剂,170℃再生时的性能最好,130℃次之,210℃最差。

Adsorption performance of alkali modified activated carbon to VOCs

Three kinds of activated carbons modified by sodium hydroxide were used to study their adsorption performances to 4 representative VOCs,such as butanone,ethyl acetate,toluene and carbon tetrachloride. The results showed that：The adsorption performance of alkali modified activated carbon was greatly improved,and there was a positive correlation between the adsorption capacity and the specific surface area of the activated carbon,which was mainly provided by the micropores;The adsorption of organic gases on the modified activated carbon was mainly physical adsorption;The adsorption capacity of the adsorbent had a linear correlation with the molecular weight,density and melting point of the adsorbate,while a poor correlation was presented with the boiling point,saturated vapor pressure and molecular dynamics diameter of the adsorbate;For the same adsorbent,170 ℃ was the suitable regeneration temperature,then 130 ℃,and 210 ℃ gave the unsatisfactory result.