Coating technology research of SCR catalysts used for marine NOx removal
Coating technology is very important to the monolithic coated SCR catalyst.The key factors affecting the preparation process of the slurry and the coating process were investigated in this paper.The effects of dispersant,thickener,pH,and solid content on the coating effectiveness and activity test results were studied.Different coating methods,slurry stirring durations,drying temperatures and times,as well as calcination temperatures and durations,were compared to optimize the coating process.It is shown that the SCR activity of coated catalysts prepared under the optimal conditions exceeds 85%in the range of 250-450℃.The denitrification activity can still be stable at over 90%at 315℃for 30 h.In this paper,the selection and application of key parameters in the coating process are systematically studied,which will provide guidance for the preparation of the monolithic honeycomb coated catalysts.