Additives to cracking catalyst based on MeOx/Al2O3 systems (Me = Cu, Fe, Ce, Co, Mn and La) to reduce the content of nitrogen oxides in regeneration gases

The influence of the nature of nitrogen-containing compounds introduced into a model cracking feedstock (n-hexadecane) on the composition of regeneration gases formed during catalyst regeneration was studied. An increase in the content of CO and NO x in the composition of regeneration gases was observed with an increase in the basicity and molecular weight of nitrogen compounds in the range: pyridine < n-butylamine < pyrrole < quinoline < indole. The effect of a Pt-based CO promoter on the composition of regeneration gases was studied. The use of a CO promoter reduces CO emissions by 99.4% but leads to a significant increase in NOx emissions. Additives were synthesized and studied to reduce the content of nitrogen oxides in the regeneration gases of a cracking catalyst. The additives were mixed oxides containing Cu, Fe, Ce, Co, Mn and La deposited on γ-alumina. The use of these additives at the stage of regeneration of the cracking catalyst led to a decrease in the content of nitrogen oxides formed during regeneration. For an additive based on copper oxide, the efficiency of reducing the content of nitrogen oxides in regeneration gases reached 12.2%.