Aromatization catalyst and preparation process and use thereof

An aromatization process for producing aromatic hydrocarbons from a lower alkane, comprising:

• contacting the lower alkane with an aromatization catalyst consisting of an inorganic oxide and a modified Ga-ZSM-5 zeolite consisting of a modified ZSM-5 zeolite with a hierarchical macro-meso-microporosity and gallium deposited in channels of or on surfaces of the modified ZSM-5 zeolite, or both;
• wherein the aromatization is carried out at a temperature of 500° C. to 550° C. under normal pressure at a weight hourly space velocity of 0.3 h−1 to 2 h−1,
• wherein a process for preparing the aromatization catalyst comprises:
• (a) adding a silicon source into a mixed aqueous solution containing an aluminum source and a first structure directing agent to perform a hydrothermal reaction so as to obtain a first solid product, which is then subjected to calcination to obtain a ZSM-5 zeolite precursor;
• (b) mixing the ZSM-5 zeolite precursor with water and a second structure directing agent together to perform a hydrothermal treatment so as to obtain a second solid product, which is then subjected to calcination;
• (c) subjecting a product resulting from the calcination in step (b) to an alkali treatment so as to obtain a hierarchical ZSM-5 zeolite;
• (d) subjecting the obtained zeolite to be modified with ammonium ions and then calcined to obtain the modified ZSM-5 zeolite;
• (e) subjecting the modified ZSM-5 zeolite to be ion-exchanged with a solution of gallium salt and then to be calcined to obtain the modified Ga-ZSM-5 zeolite;
• and
• (f) mixing the modified Ga-ZSM-5 zeolite with an inorganic oxide precursor, followed by shaping, drying, and then calcination, to yield the catalyst.