Transalkylation Of Benzene With Triisopropylbenzene Over MCM-49 Zeolite

A dynamic hydrothermally method was used to synthesize MCM-49 zeolite by taking the sodium aluminum as aluminum source, the silicon sol as silicon source and the HMI as directing agent in a reaction gel. After the preparation in a 100ml crystallization kettle, MCM-49 zeolite was prepared successfully in a 1L crystallization reactor. When the alkalinity of the solution was higher than 0.17, a material, modenite, was formed. While the alkalinity of the solution decreased to nearby 0.11, the product was MCM-49 zeolite. Modifications of MCM-49 were carried out by adding ethanol. The XRD spetra was not changed with small amount of ethanol and the amounts of strong acid increased after modification by the characterization of XRD and NH3-TPD.Transalkylation of benzene with triisopropylbenzene was performed over the MCM-49 zeolite. Influences of the WHSV, the B/TIPB molar ratio and the temperature on the conversion of TIPB and selectivities of DIPB and IPB were investigated. Compared modenite, MCM-49/βcomposite zeolite, and MCM-49 zeolites, ehanol-modified MCM-49 was more active than the other catalysts.The activity of ethanol-modified MCM-49 was always higher than BETA zeolite in the range of temperature studied. Comparing ethanol-modified MCM-49 with MCM-49/βcomposite zeolite, it was found that ethanol-modified MCM-49 was better than MCM-49/βwhen temperature was lower than 200℃in the transalkylation of benzene with triisopropylbenzene. If the temperature was higher than 200℃, it was more appropriate to choose MCM-49/βcomposite zeolite.