Aromatization of butane on Pt–Ge intermetallic compounds supported on HZSM-5 Original Research Article

Catalytic properties of Pt–Ge intermetallic compounds supported on HZSM-5 zeolites were studied in the conversion of butane into aromatic hydrocarbons under atmospheric pressure at 823 K. Pt–Ge intermetallic compounds were prepared on HZSM-5 by chemical vapor deposition of Ge(acac)2Cl2 on Pt-loaded HZSM-5 followed by the treatment with hydrogen at 823 K. XRD revealed the transformation of Pt particles into the intermetallic phases, Pt2Ge, Pt3Ge2, PtGe, Pt2Ge3 and PtGe2, during the CVD and subsequent hydrogen treatment. In the reaction of butane, Pt–Ge intermetallic compounds supported on HZSM-5 exhibited higher selectivity to aromatic hydrocarbons than HZSM-5 and Pt-loaded HZSM-5. This would be caused by the high activity for the dehydrogenation of butane and alkylcyclohexene compared with HZSM-5 and the low activity for the hydrogenolysis and hydrogenation to form methane and ethane compared with Pt-loaded HZSM-5. Pt–Ge intermetallic compounds with Pt/Ge molar ratio of 1.0 supported on HZSM-5 showed the highest selectivity to aromatic hydrocarbons (57 C%). PtGe was suggested to be the most effective for the formation of aromatic hydrocarbons from butane among the Pt–Ge intermetallic compounds.