在臭氧单独作用、紫外光单独作用和UV/O33种条件下分别对甲醛进行降解试验,研究表明,臭氧和紫外在降解甲醛的试验中存在明显的协同促进作用。单独臭氧对甲醛降解效果并不显著。紫外单独作用时,对甲醛几乎没有降解作用。在UV/O3条件下,甲醛的降解率大大提高,特别是在高浓度臭氧条件下,降解率高达63%。臭氧浓度增大,降解率增大;紫外光强度增大,降解效果提高;气体流量增大,降解率下降;湿度增大,降解率提高。对甲醛降解试验进行动力学研究,结果表明,光照强度和臭氧浓度增大,一级反应速率增大,提高臭氧浓度要比加强紫外强度更能促进甲醛的降解。
Degradation of HCHO experiment in the ozone alone, UV alone, and O3/UV conditions were studied. The results showed that the combination of ozone and ultraviolet existed obvious synergies. The degradation of formaldehyde by ozone was not significant. UV alone condition had weak effect on formaldehyde degradation. Under UV/O3 conditions, the conversion of HCHO was greatly improved, particularly in high concentrations of ozone,the conversion was high as 63%. The degradation of HCHO increased with the increasing of ozone concentration, UV intensity and humidity, but it decreased with the increase of gas flow velocity. The dynamic analysis of the experiment showed the first order decomposition rate constants of HCHO increased with the increasing of ozone concentration and UV intensity. And the supplement of ozone promoted the decomposition of HCHO than the enhancement of UV light intensity.