Effect of redox atmosphere treatment on bifunctional Ga/ZSM-5 for efficient catalytic cracking of n-butane

Ga species with high dehydrogenation capability were prepared by H₂-O₂ atmosphere treatment, and efficient balance of bifunctionality (dehydrogenation/cracking) was realized between Ga species and ZSM-5 over Ga/ZSM-5 based catalysts. Compared with parent Ga/ZSM-5, the conversion rate of n-butane was increased from 0.53 to 2.59 mmol·g⁻¹·min⁻¹ on Ga/ZSM-5 with H₂-O₂ treatment. Kinetic analysis revealed that the apparent activation energy of n-butane catalytic cracking decreased largely from 141 to 47 kJ·mol⁻¹, which is attributed to the formation of new interaction between Ga species and ZSM-5 upon such an atmosphere treatment. It was also found Butane-O₂ treatment acted as a similar role with H₂-O₂ treatment in enhancing the catalytic performance. On this basis, different Ga species were correlated with activity and kinetic data, and the effect of practical reaction atmosphere on Ga species was also investigated.