Patent · US Active

Honeycomb filter system

US7972400B2 · kind B2 · utility

7Cited by
3References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 7, 2008
Grant dateJul 5, 2011
Priority date
Expiry dateJan 17, 2029

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S55/30
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

A honeycomb filter system comprising a first honeycomb filter disposed upstream: first filter having partition wall matrix of a mean pore diameter of 25 μm or more and below 70 μm and a porosity of 40% or more and below 70%, and carrying an oxidation catalyst containing at least one material selected from the group consisting of platinum (Pt), palladium, ceria, and alumina in at least a part of inner surfaces of pores of the matrix; and a second honeycomb filter disposed downstream; having a surface layer of a peak pore diameter of 0.3 μm or more and below 20 μm which is equivalent to or smaller than that of its matrix, and a porosity of 60% or more and below 95% which is higher than that of the matrix; and having the other specified relations.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.