Modified ZSM-5 Zeolite for Conversion of LPG to Aromatics
Abstract
Conversion of LPG as an abundance and cheap feedstock to valuable aromatic compounds was studied over modified ZSM-5 zeolite. First, optimum reaction conditions such as temperature, wight hour space velocity (WHSV) and feedstock composition were obtained. Subsequently, Ga and Zn were used as suitable metals for catalyst promotion. Zeolite/metal ratios between 0.2 and 1%wt. were papered and were tested in WHSV values of 3 to 12, temperatures between 470 and 510 °C and propane, butane, and LPG as feed. Results showed Ga-promotion in low concentrations influences catalyst lifetime and aromatic selectivity for butane cut, while Zn made the same development for propane feed at high concentrations. As an interesting fact, it was observed that Ga wins the competition with Zn when LPG in consumed as feed in a slight difference. Promoter selection between Ga and Zn depends on LPG composition which in this research Ga showed better performance according to the industrial feed.