改性活性炭净化室内空气中甲醛和苯系物的应用研究

A Study on the Application of Modified Activated Carbon to Removing Formaldehyde and Benzene Series Compounds from Indoor Air

室内空气污染物中,甲醛和苯系物对人体健康最具威胁,研究改性活性炭对室内空气中甲醛和苯系物的净化性能有重大意义。选用3种不同的改性活性炭,对其表面积、孔结构及化学元素组成等进行测试;采用液相衍生方法评估对甲醛的吸附降解性能;采用气相顶空方法评估对苯系物的吸附降解性能。结果表明,改性活性炭对甲醛和苯系物的物理吸附主要取决于微孔、中孔结构和孔分布,化学吸附主要取决于表面不同类型的官能团;同1种活性炭对甲醛和苯系物有不同的吸附性能,取决于污染物的沸点、分子量、饱和蒸气压、极性等。要结合改性活性炭的结构组成,充分利用改性活性炭的物理化学协同吸附作用,使其在空气净化中得到更好的应用。

Of myriad indoor air pollutants, formaldehyde and benzene series compounds pose a threat to human health the most, so that to research modified activated carbon for cleaning them from indoor air will be of great significance. Three kinds of modified activated carbon were selected to test their superficial areas, pore structures, constituents of chemical elements, and etc. HPLC derivative method was used to test their performance of adsorbing and degrading formaldehyde, and GC top space method was used to evaluate their performance of adsorbing and degrading benzene series compounds. It has indicated that the physical adsorption of formaldehyde and benzene series compounds by modified activated carbon is highly dependent on its microporous and mesoporous structures as well as pore distribution, whilst the chemical adsorption relies on its different types of surfacial functional groups. In respect to the same kind of activated carbon, its adsorptive performance may vary depending on the properties of pollutants including boiling point, molecular weight, saturated vapour pressure, polarity, and etc. It would be needed to consider the structural composition of modified activated carbon for full use of its physico-chemical synergistic adsorption so as to further improve its application to air cleaning in the future.