Study On The Catalytic Denitration Performance Of Metal Doping Cu-ZSM-5 Catalyst

Nitrogen oxide(NOx)is one of the main pollutants of photochemical smog,acid rain and the destruction of the ozone layer,and have great damage to human body health,industrial and agricultural production and ecological environment.At present,the main nitrogen oxide processing techniques includ pre-combustion control technology,selective catalytic reduction technology,selective non-catalytic reduction technology and direct catalytic decomposition technology.Among them,the direct catalytic decomposition technique by eliminating the need to add a reducing agent without secondary pollution is concerning.In this paper,Cu-ZSM-5 catalyst with heteroatom is synthesized by hydrothermal synthesis method using silica sol as silica source and sodium aluminate as aluminum source.Then changing the synthesis conditions of it is to prepare a series of catalysts.And using simulated flue gas exams the catalyst activity of them on NO decomposition reaction.The study finds that the best catalytic effect is achieved under the condition of 60 silica alumina ratio,17 silicon bronze ratio,pH of 10-12,165°C crystallization temperature and crystallization time 24 hours,the space velocity and O2 volume fraction have effection stability of the catalyst.Denitration test results show that the modification effect of ion doping followed by K+> Mg2+> Ca2+,compared with the noble metal doped Zr-Cu-ZSM-5,the catalytic effect of K-Cu-ZSM-5 is better.Characterization results showed that: In terms of the carrier,a high degree of crystallinity structure without impurity phase of molecular sieve is the activity of catalyst has the basic conditions,carrier having an appropriate size,the grain surface clean will help improve the activity of the catalyst;in terms of catalyst active component,uniformly distribution of the active materialon on catalyst surface and reducing agglomeration,help to improve catalyst activity help to improve catalyst activity,large effective surface area and pore volume can increase the catalyst activity,and a uniformmesoporous pore size also help to improve the catalytic activity,also found Cu+,and weak acid position is more conducive to improve the catalytic activity.