Benzene reduction in gasoline by olefin alkylation: Effect of the catalyst on a C6-reformate heart-cut

The study presented here compares the performance of different zeolite catalysts (Beta, ZSM-5 and Beta:ZSM-5 composites) for benzene alkylation by propylene with a benzene enriched reformate heart-cut (13 wt% benzene). The experiments were carried out in a batch system with a 1/1 benzene:propylene mole ratio at 220 °C for 1 h. The results showed that an increase in conversion produced decreases in cumene selectivity and oligomers formation. These results were associated to Beta contained catalysts. Lower conversions related to a higher oligomers production and lower di-isorpropylbenzene isomers formation, were obtained with a ZSM-5 catalyst. Results were compared with pure benzene/propylene alkylation tests carried out at similar experimental conditions.

The production of a more environmentally suitable gasoline by removing substantial portions of benzene by alkylation with propylene was studied on a real feedstock with Beta, ZSM-5 and Beta:ZSM-5 composites as catalysts. Beta catalyst was associated with higher benzene conversions and cumene and di-isopropylbenzene (DIPB) isomers formation. Lower conversions with high oligomers production were obtained with a ZSM-5 catalyst.Figure optionsDownload as PowerPoint slide