Transalkylation of 1,3,5-triethylbenzene (TEB) with ethylbenzene (EB) has been studied over ZSM-5... more Transalkylation of 1,3,5-triethylbenzene (TEB) with ethylbenzene (EB) has been studied over ZSM-5 zeolite using a riser simulator reactor with respect to optimizing DEB yield. The reaction temperature was varied from 350 to 500 °C with contact time ranging from 3 to 15 s to report on the effect of reaction conditions on TEB conversion, DEB selectivity and isomerization of TEB. The transalkylation of TEB with EB was compared with the reactions of pure 1,3,5-TEB and EB (disproportionation, isomerization and cracking). A synergistic effect was observed on the conversion of 1,3,5-TEB and DEB yield. The 1,3,5-TEB conversion increased from 40% to 50% with simultaneous increase in the DEB selectivity from 17% to 36% in transalkylation reaction (EB + 1,3,5-TEB) as compared with the reaction of pure 1,3,5-TEB. It was found that pure 1,3,5-TEB underwent cracking reaction to produce DEB and EB. The isomerization of 1,3,5-TEB was more active at low temperature while cracking was more active at high temperature. The temperature of 350 °C was observed as the optimum for production of maximum amount of DEB. Kinetic parameters for the disappearance of 1,3,5-TEB during its transformation reaction via cracking and isomerization pathways were calculated using the catalyst activity decay function based on time-on-stream (TOS). The apparent activation energies decrease in order Esecondary cracking > Eprimary racking > Eisomerization for ZSM-5 catalysts.
Catalytic transformation of 1,3,5-Trimethylbenzene (TMB) has been investigated over USY zeolite c... more Catalytic transformation of 1,3,5-Trimethylbenzene (TMB) has been investigated over USY zeolite catalyst in a novel riser simulator at different operating conditions. The effect of reaction conditions on the variation of isomerization to disproportionation products ratio (I/D), distribution of trimethylbenzene (TMB) isomers, xylene/tetramethylbenzenes (X/TeMB) ratio and values of p-xylene/o-xylene (P/O) ratios are reported. Comparisons are made between the results of the 1,3,5-TMB and the earlier reported values of 1,2,4-TMB under similar conditions. Even though the kinetic diameters of these molecules slightly exceed the pore size of the USY zeolite (7.4Å), they still have access to the openings of the zeolite pore due to their flexibility. They are readily accommodated inside the zeolite channel system thereby allowing reaction to proceed. Surprisingly, 1,3,5-trimethylbenzene was found to be more reactive than 1,2,4-trimethylbenzene at temperatures above 450 oC and reaction times ...
Transalkylation of 1,3,5-triethylbenzene (TEB) with ethylbenzene (EB) has been studied over ZSM-5... more Transalkylation of 1,3,5-triethylbenzene (TEB) with ethylbenzene (EB) has been studied over ZSM-5 zeolite using a riser simulator reactor with respect to optimizing DEB yield. The reaction temperature was varied from 350 to 500 °C with contact time ranging from 3 to 15 s to report on the effect of reaction conditions on TEB conversion, DEB selectivity and isomerization of TEB. The transalkylation of TEB with EB was compared with the reactions of pure 1,3,5-TEB and EB (disproportionation, isomerization and cracking). A synergistic effect was observed on the conversion of 1,3,5-TEB and DEB yield. The 1,3,5-TEB conversion increased from 40% to 50% with simultaneous increase in the DEB selectivity from 17% to 36% in transalkylation reaction (EB + 1,3,5-TEB) as compared with the reaction of pure 1,3,5-TEB. It was found that pure 1,3,5-TEB underwent cracking reaction to produce DEB and EB. The isomerization of 1,3,5-TEB was more active at low temperature while cracking was more active at high temperature. The temperature of 350 °C was observed as the optimum for production of maximum amount of DEB. Kinetic parameters for the disappearance of 1,3,5-TEB during its transformation reaction via cracking and isomerization pathways were calculated using the catalyst activity decay function based on time-on-stream (TOS). The apparent activation energies decrease in order Esecondary cracking > Eprimary racking > Eisomerization for ZSM-5 catalysts.
Catalytic transformation of 1,3,5-Trimethylbenzene (TMB) has been investigated over USY zeolite c... more Catalytic transformation of 1,3,5-Trimethylbenzene (TMB) has been investigated over USY zeolite catalyst in a novel riser simulator at different operating conditions. The effect of reaction conditions on the variation of isomerization to disproportionation products ratio (I/D), distribution of trimethylbenzene (TMB) isomers, xylene/tetramethylbenzenes (X/TeMB) ratio and values of p-xylene/o-xylene (P/O) ratios are reported. Comparisons are made between the results of the 1,3,5-TMB and the earlier reported values of 1,2,4-TMB under similar conditions. Even though the kinetic diameters of these molecules slightly exceed the pore size of the USY zeolite (7.4Å), they still have access to the openings of the zeolite pore due to their flexibility. They are readily accommodated inside the zeolite channel system thereby allowing reaction to proceed. Surprisingly, 1,3,5-trimethylbenzene was found to be more reactive than 1,2,4-trimethylbenzene at temperatures above 450 oC and reaction times ...
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