Kinetic modeling an‎d experimental investigation of selec‎ted variables in the conversion of Methanol to Aromatics

1/1/1900 12:00:00 AM

Considering that Iran is one of the largest methanol producing countries an‎d the conversion of methanol to various hydrocarbons is considered an important step in natural gas conversion processes, in this particular, the general process of converting methanol to aromatics (MTA) can be considered as a process for converting methanol. Give more names to products with added value. In this thesis, the aim is to achieve optimal operating conditions in the conversion of methanol to aromatic compounds in the presence of ZSM-5 zeolite catalyst an‎d to investigate the kinetics of chemical reactions carried out in the process of converting methanol to aromatics.In this research, ZSM-5 catalyst with SiO2/Al2O3 ratio of 80, 60, 40, 20, 10 was synthesized an‎d 10 ratio was chosen as the selec‎ted catalyst in reactor tests, ZSM-5 catalyst with SiO2/Al2O3 =10 ratio according to According to TPD analysis, it has higher acidity, an‎d this makes cracking reactions less an‎d aromatization an‎d dehydrogenation increase. In this research, after the initial construction an‎d eva‎luation of the catalyst, the operating parameters were investigated an‎d optimized, an‎d the desired range for each of the operating parameters (temperature-pressure-LHSV) was obtained through successive tests, an‎d in the next stage, the experimental an‎d optimal design was carried out. Variables were created by Box-Benhken method.The results of the reactor test showed the appropriate performance of the selec‎ted catalyst in the conversion of methanol to aromatic compounds. Similarly, the investigations indicate the high effect of temperature on the rate of methanol conversion an‎d its selec‎tivity towards aromatics, so that at a constant LHSV of 0.5, with an increase in temperature from 280°C At 340°C, the selec‎tivity towards aromatics increases by about 6%. The optimal temperature of the process was 350°C, LHSV 0.5 an‎d pressure 12.5 bar, an‎d the selec‎tivity of the produced aromatics was 65%. The design of experiments in order to achieve optimal operating conditions in the conversion of methanol feed to aromatics showed that with increasing temperature an‎d decreasing space velocity, methanol feed conversion an‎d selec‎tivity to aromatics increased. In this research, the kinetic model of 8 reactions carried out during the process without considering the deactivation of the catalyst with coke deposition has been investigated, an‎d finally, by matching the first-order kinetic model with experimental data through the numerical method presented in the report, K0 an‎d the activation energies of each reaction were calculated an‎d the speed of reactions can be obtained at any temperature. It was also calculated that the correlation coefficient (R2) for Arrhenius diagrams is more than 0.9, which shows the good compatibility of experimental data with theoretical data.

زئوليت , آروماتيك سازي متانول

ZSM5 zeolite , methanol aromatization

maedefallahian

soroush baradaran