ترجمه مقاله نقش ضروری ارتباطات 6G با چشم انداز صنعت 4.0
- مبلغ: ۸۶,۰۰۰ تومان
ترجمه مقاله پایداری توسعه شهری، تعدیل ساختار صنعتی و کارایی کاربری زمین
- مبلغ: ۹۱,۰۰۰ تومان
ABSTRACT
Though p-xylene derived from naphtha reformate is in high demand as a raw material in the production of polyesters and polyethylene terephthalates, its separation from the FCC reformate is not easy due to close boiling points among the components in the reformate. When a proper solvent for the p-xylene separation is available, an extractive distillation can be applied in the separation. Currently the separation utilizes an adsorption process requiring a large amount of costly adsorbent and a desorption process followed by distillation. In the proposed extractive distillation here, p-dinitrobenzene has been utilized to improve the separation of p-xylene from its ethylbenzene mixture. The VLE data of the ternary mixture estimated with the UNIFAC were compared to those computed from molecular simulation to show their reliability. An extractive distillation and solvent recovery were applied to obtain 99.6% purity p-xylene with 99.1% recovery. The economics of the proposed process demonstrates its comparability to the existing Parex process.
6. Conclusions
An extractive distillation process for the separation of ethylbenzene and p-xylene was developed, and its design procedure was presented here. The solvent used in the process has similar structure of p-xylene with higher boiling point. The molecular simulation in the ternary system of ethylbenzene/p-xylene/p-dinitrobenzene indicates that the solvent improves the separation factor between ethylbenzene and pxylene. The design results of the extractive distillation and solvent recovery columns are presented, and the economics of the proposed process was briefly compared to that of the Parex process. The process design demonstrated the feasibility of distillation separation of ethylbenzene and p-xylene with 99.1% recovery and 99.6% purity of p-xylene. The economic evaluation also exhibits the distillation process is comparable to the adsorption process, a current commercial process. The VLE computation in a ternary system using the molecular simulation was applied to the examination of the NRTL thermodynamic model for the ternary system.