화학공학소재연구정보센터
Industrial & Engineering Chemistry Research, Vol.49, No.3, 1252-1258, 2010
High Surface Area Mn,Mg,Al-Spinels as Catalyst Additives for SOx Abatement in Fluid Catalytic Cracking Units
Mn,Mg,Al-spinels derived from hydrotalcite-like compounds with different Al/(M2- + Al) molar ratios, (0.25 and 0.50) and Mn/Mg of 0.30 were evaluated as catalysts for SOx removal under conditions similar to those found in fluid catalytic cracking (FCC) units. For both samples, the maximum rate of SOx pickup took place in the first 5 min of reaction, which is all interesting feature since the contact time inside the FCC regenerator is about 5-10 min. As to the regeneration step, propane seems to he a less effective reducing agent than hydrogen since it favored the release of SO2 as reduction product and shifted the reduction profile to higher temperatures. The results from XRD indicate that SO2 was mainly fixed as MgSO4, although the formation of MnSO4 has been indirectly evidenced. The performance of both samples for SOx uptake and sulfur release was also evaluated in the presence of CO and NO and no adverse effect was observed. The obtained results suggest that Mn-containing spinels are promising additives for SOx removal.