Process for removing nitrogen oxides
US4946661A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 15, 1988 |
| Grant date | Aug 7, 1990 |
| Priority date | — |
| Expiry date | Nov 15, 2008 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01J35/66
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A process for removing nitrogen oxides from exhaust gases containing volatile metal compounds with good efficiency by contacting the gases with a catalyst comprising TiO.sub.2, difficulty reduced by the compounds, in the presence of ammonia, and such a catalyst are provided, which process is characterized in that the average pore diameter of the TiO.sub.2 is 10,000 .ANG. or less and the proportion of the volume of pores having pore diameters of 400-5,000 .ANG. to the total pore volume is 50% or more; a denitration-active component is supported on the TiO.sub.2 ; a catalyst carrier precursor comprising an aqueous slurry sol of TiO.sub.2 or Ti hydroxide prepared by hydrolyzing a Ti salt is precalcined at 150.degree.-700.degree. C., followed by adding a denitration-active component and then normally calcining the mixture; and a polymer compound having a thermal decomposition temperature of 110.degree. to 300.degree. C. is added in 1-20% by weight to the catalyst carrier precursor, followed by precalcining the mixture at the thermal decomposition temperature or higher.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.