TiO_2光催化氧化脱除模拟烟气中的NO_x

Removal of NO_x from simulated flue gas by photocatalytic oxidation using TiO_2

采用P25纳米Ti O2为催化剂,对NOx浓度360 mg/m3的模拟烟气进行了光催化氧化实验研究,以期为此种方法在电厂烟气脱硝方面的应用提供依据。经SEM、XRD等表征手段,探讨了催化剂晶型尺寸对光催化的作用。实验考察了光催化反应过程规律以及负载量、光照度、NO初始浓度、O2含量、相对湿度和停留时间对光催化氧化效率的影响。结果表明,光催化反应是瞬态到稳态的过程,其催化效率与上述影响因子有密切关系。实验最优条件下NOx的脱除率为46%,但只需适当提高氧化效能,便能达到理想的效果。

Taking P25 nano-Ti O2 as photocatalyst,phtocatalytic oxidation experiments for treating NOx,of which concentration was around 360 mg / m3,from simulated flue gas were carried out. It was expected to provide reference in terms of flue gas denitrification of power plants. By characterizing with SEM and XRD,the effects of photocatalyst's crystal type and particle size on photocatalysis were discussed. The regular pattern of photocatalytic process,as well as influences of some key factors: loading capacity of Ti O2,illumination intensity,NO inlet concentration,content of O2,relative humanity,residence time on photocatalytic efficiency,were investigated in the experiments. The results showed that the process of photocatalytic reaction was a course from transient state to stable state,and the photocatalytic efficiency was closely related with the influencing factors mentioned above.Under optimal conditions of photocatalytic experiments,46% removal efficiency of NOxwas achieved. Ideal denitrification effect could be got if necessarily we had improved the oxidation performance to a certain extent.