摘要
Mg-doped manganese oxide octahedral molecular sieve(Mg-OMS-2)catalysts were prepared by hydrothermal method.The photothermal degradation performance of these catalysts for formaldehyde(HCHO)in batch system and continuous system was investigated.The light absorption of OMS-2 was increased by Mg-doped,especially for near infrared light,which promoted surface temperature reach a maximum of 214.8℃ under xenon irradiation.At this temperature,the reinforced surface lattice oxygen and oxygen vacancy that formed by lattice distortion via Mg-doped were activated.The best HCHO elimination efficiency was achieved over Mg_(0.2)/OMS-2 catalyst with Mg^(2+)/Mn^(2+)=1/5,which could reduce HCHO from 250 ppm to 10 ppm within 20 min.The in situ DRIFTS was also carried out to monitor the changes in the content of reaction intermediates and analyze the degradation paths of HCHO.It was found the HCHO was attacked by formed·OH and·O^(2-) to generate formate species and carbonate species,and finally transformed to CO_(2) and H_(2)O.This photothermal catalytic oxidation process exhibited a high efficiency purification of HCHO without the help of extra energy consumption.
基金
financially supported from the Natural Science Foundation of China(No.51908491)
the Ministry of Science and Technology Project of China(No.2017YFE0127400)
the Zhejiang Provincial Natural Science Foundation of China(No.LY20B070001)。
