(TW211527-A)      A process for destroying nitrogen oxides and carbon monoxide in a combustion product, which process comprises: (a) combusting a fuel source in the presence of oxygen to form a combustion product comprising nitrogen oxides, carbon monoxide and oxygen; (b) introducing methane into the combustion products in an amount such that the total amount of methane to nitrogen oxides present expressed as a ratio, by volume is greater than 0.1; and (c) reacting the combustion products, methane and oxygen in the presence of a catalyst comprising a crystalline zeolite having a silicon to aluminum ratio of greater than or equal to about 2.5 which is exchanged with a cation selected from the group consisting of cobalt, nickel, iron, chromium, rhodium, gallium and manganese, under conditions sufficient to convert a portion of the nitrogen oxides and carbon monoxide to gaseous nitrogen, water and carbon dioxide, in which the reacting of the combustion products in the presence of the catalyst is conducted at temperatures ranging from 250 to 700 C, pressures ranging from 0.5 to 300 atmospheres, and in a fixed bed reactor with air retention speed of 1000 hr-1 to 100000 hr-1.    (ZA9206819-A)      Nitrogen oxides (NOx) and carbon monoxide in a combustion product are destroyed by (a) combusting a fuel source (I) in presence of oxygen to form a combustion product (II) comprising NOx, CO and O2; (b) introducing methane into (II), to give CH4:NOx vol. ratio greater than 0.1; and (c) reacting the mixture in presence of a catalyst comprising a crystalline zeolite of Si:Al ratio at least 2.5 which has been exchanged with a cation (III) of Co, Ni, Fe, Cr, Rh, Ga or Mn, to convert a portion of the NOx and CO to gaseous N2, H2O and CO2.    USE/ADVANTAGE -   The combustion products may be flue gas or exhaust from a mobile or stationary engine; the fuel may be 1-15C gaseous or liquid hydrocarbon, coal, oil or refuse; there is high conversion of NOx and CO to environmentally safe products.    (JP95049095-B2)      Nitrogen oxides (NOx) and carbon monoxide in a combustion product are destroyed by (a) combusting a fuel source (I) in presence of oxygen to form a combustion product (II) comprising NOx, CO and O2; (b) introducing methane into (II), to give CH4:NOx_ vol. ratio greater than 0.1; and (c) reacting the mixture in presence of a catalyst comprising a crystalline zeolite of Si:Al ratio at least 2.5 which has been exchanged with a cation (III) of Co, Ni, Fe, Cr, Rh, Ga or Mn, to convert a portion of the NOx and CO to gaseous N2, H2O and CO2.    USE/ADVANTAGE -   The combustion products may be flue gas or exhaust from a mobile or stationary engine; the fuel may be 1-15C gaseous or liquid hydrocarbon, coal, oil or refuse; there is high conversion of NOx and CO to environmentally safe products.