AgCu/HZSM-5上甲醛和苯的共吸附及等离子体氧化脱除

Co-adsorption of Formaldehyde and Benzene and Decomposition by Plasma Oxidationover AgCu/HZSM-5

为治理室内空气中多种气体污染物,本实验以AgCu/HZSM-5为吸附剂,研究了湿空气中甲醛和苯混合气体污染物的共吸附及等离子体氧化脱除性能.实验结果表明:AgCu/HZSM-5对甲醛和苯有良好的共吸附性能,97.4%的吸附态甲醛和苯被O_2等离子体氧化为CO_2.运用程序升温氧化技术对等离子体氧化后残留含碳物种进行分析,推测苯与Ag形成强络合吸附是碳平衡较差的主要原因.初步考察了共吸附—等离子体氧化过程中AgCu/HZSM-5的稳定性.结果表明所制备的吸附剂经过一次循环后混合气体污染物中甲醛的穿透吸附性能下降约16%,未检测到苯穿透,但在随后5次循环实验中基本保持稳定,且吸附态甲醛和苯被O_2等离子体完全氧化为CO_2.

In order to remove various gaseous pollutants in indoor air,AgCu/HZSM-5 was used as adsorbent to study co-adsorption of mixed gaseous pollutants of formaldehyde and benzene in moist air,and subsequently decomposition performance by plasma oxidation. The results showed that AgCu/HZSM-5 exhibited excellent co-adsorption capacity of formaldehyde and benzene,and 97. 4% of adsorbed formaldehyde and benzene was oxidized to CO_2 by O_2 plasma. The residual carbon species after plasma oxidation were analyzed by the temperature programmed oxidation technique,and the poor carbon balance might be caused by the complexation adsorption between Ag and benzene. Preliminary study on the stability of AgCu/HZSM-5 during adsorption-plasma oxidation process was investigated. The results showed that the breakthrough capacity of HCHO decreased by about 16% after the first cycle,but kept almost the same stability during the following five cycles,and no benzene was detected in the whole experiment. Meanwhile,almost all adsorbates were completely oxidized to CO_2 except the first cycle.