Three-component catalysts - for gas purification

摘要

Catalysts for gas purification are composed of the association of a solid conductive metallic promoter and two other catalytic substances, >=1 of which is a metallic oxide whose conductivity increases with temp. The promoter can be a Group V, VI, or VIII metal or an actinide, e.g. Th, U, Ru, V, Co, Ni, Ir, or Pd. The other catalytic substances may be Cu, Zn, Cr, Mo, Co, Ni, Al and their oxides, nitrates of chlorides. In an incomplete reduction step, the three substances are reduced at below the reduction temp. of one of the three substances. The catalysts have an improved gas adsorption, due to the relatively constricted size of the internal pores.