Based on the current understanding of the nature of the propane aromatization catalyst

the catalytic activity of Ga modified HZSM-5 prepared by different impregnation methods is studied

including incipient wetness

vacuum assisted incipient wetness

and microwave assisted incipient wetness impregnations. With the help of various catalyst characterization techniques

the microscopic changes of the catalysts after modification were examined. The result showed that methods of impregnation had significant effects over dispersion of Ga species on the surface of the catalysts where vacuum assisted impregnation was proved to have the best results. At reaction temperature of 525℃

propane WHSV=1 h-1

product sampled after 1.3 h of propane on stream time suggested a propane conversion of 93.8%

liquid aromatization yield of 57.2% and BTX yield of 48.6%. Vacuum assisted impregnation methods led to better Ga distribution thereby reduced B acid sites and increased L acid sites. This modification resulted in inhibited propane cracking

increased dehydrogenation and aromatization reactions

as well as a longer catalyst life.