摘要:
A catalyst for low-temperature decomposition of dmitrogen oxide in tail gases from a nitric acid plant based on cobalt oxide comprises, calculated as simple oxides: cobalt oxide at the level of 45.00-99.97 weight %, nickel oxide at the level of 0.01-30.00 weight %, zinc oxide at the level of 0.01-20.00 weight % as principal structural components and activity promoters in the form of alkali metals, such as Na and/or K, at the level of 0.01-5.00 weight % and shape-facilitating alkaline earth metal oxides, such as Ca and/or Mg, at the level of 0.01-5.00 weight %. The invention provides also a process for the preparation of a catalyst.
摘要:
A composite catalyst according to the present invention contains cobalt oxide at 25 - 88.6 % by weight, zinc oxide at 10.99 - 60 % by weight as the substantive components, wherein the zinc oxide is introduced in two stages, during precipitation as well as prior to the forming of the catalyst. The ratio of zinc oxide introduced during the precipitation to the zinc oxide added prior to the forming of the catalyst is 1 :0.26-13.3and it also contains components which improve activity, in the form of alkali metals at 0.01 -5 % by weight calculated in terms of oxides of these metals, and graphite at 0.4-10 %. Preferably, the alkali metals present in the catalyst composition are sodium and/or potassium.