Catalyst And Process Development For Alkylation Of Benzene With Methanol

In this paper, ZSM-5 and ZSM-11 was modified to produce toluene and xylene by the reation of benzene alkylation with methanol. The modification conditions was Optimized. Samples were characterized by XRD、FE-SEM、NH3-TPD、N2-physisorption techniques, respectively. The effect of acdity and pore structure to reaction was discussed. The results showed that the two-step process including alkali and acid treatment introduced a number of mesoporous in molecular sieves and changed the acidity. The amount of total acid increased in high Si/Al molecular sieves, however, it decreased in low Si/Al molecular sieves. The strong acid decrease greatly and weak acid increased when loading proper mental. Alkylation of benzene with methanol was carried out over modified ZSM-5 catalysts. The benzene conversion was 56.94%. The total selectivity of toluene and xylene was 92.14%. The xylene selectivity was 36.53%. The reactivity of modified ZSM-5 was stable in 300 hours alkylation reaction of benzene with methanol, which shows good stability. Alkylation of benzene with methanol was carried out over modified ZSM-5 catalysts. The benzene conversion was 52.60%. The total selectivity of toluene and xylene was 89.91%. The xylene selectivity was 34.08%. The reactivity of modified ZSM-11 was stable in 200 hours alkylation reaction of benzene with methanol, which shows good stability.The process conditions and dynamics of benzene alkylation with methanol over modified ZSM-11 was also researched in this paper. In the experimental range. The activation energy of benzene alkylation with methnol was 145.20KJ/mol. The pre-exponential factor was 2.4898g/(gcat · h · MPa).