| Today with the need of resorcinol increasing all over the world, the traditional sulfonatic method is not the main synthesizing way, because of its corrosive and environmentally hazardous nature. To overcome these problems, cumene oxidation method is the most prospect. Way.So 1,3-diisopropylbenzene is an important raw material in production of resorcinol. Some diispropylbenzenes(DIPBs) will be producted with the isopropylation of benzene to cumene. The work of 1,4-DIPB ismerization to 1,3-DIPB was only studied in isopropylation of benzene to cumene. In this paper, 1,4-DIPB isomerization to 1,3-DIPB on β zeolite will be studied for the first time all over the world, which is very value job.The characteristics of isomerization of DIPB on some different zeolite Catalysts were studied firstly. The results show that p zeolite is the best zeolite on the reaction of isomerization of diisopropylbenzene among Hp,HY, HMCM-22, HZSM-5 and HMCM-41. Effect of SiO2/AlO3 and the reaction conditions were studied .It was observed that As the SiO2/Al2O3 increased, the convention of 1,4-DIPB decreased but the selectivity of 1,3-DIPB enhanced, the yield of 1,3-DIPB increased then reduced.As the reaction temperature increased, the convention of 1,4-DIPB enhanced but the selectivity of 1,3-DIPB decreased on Pzeolite. When the weight hour space velocity increased the selectivity of 1,3-DIPB increased gradually. However, the conversion of 1,4-DIPB reduced on Pzeolite. In order to study the influence of raw material, the raw material was rectified under high temperature to abtain rich 1,4-DIPB containing raw material ,which was isomerized on the same catylst and conditions. The result show that raw material have no influence on this reaction.A serises of modified zeolite beta were prepared by means of ion exchange with organic acid ( tartaric acid , lactic acid and citric acid) and their ammonium salt solution. Characterization ofthe samples were analyzed by XRD, XRF, FT-IR, 27Al MAS NMR, 29Si MAS NMR, GC-MS, GC and NH3-TPD. The results show that they not only have a higher relative crystallinity than that modified by ammonium nitrate, but also can restrict the removal of framework tetrahedral Al. Besides, citric acid and ammonium citrate favor Al (S4R, SiteA) formating Al (S6R, SiteB) , while only one type of framework tetrahedral Al was found in Hβ modified by ammonium nitrate. The acid sites ,L acid sites and the strong B acid sites of Hβ-CA2 and Hβ-CA3 which were modified by ammonium citrate dibasic and triammonium citrate were more than the Hp.Hβ zeolites modified by tartaric acid, lactic acid and their ammonium salt solution have the same characters with those modified by citric acid and ammonium citrate.Hβ-TA2 has the best effect on the isomerization of diisopropylbenzene. At 200℃ the conversion of 1,4-DIPB arrives at 52.92%, and the 1,3-DIPB selectivity is 73.61%. The content of 1,3-DIPB increased to 62.32%.
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