STUDY ON MOLECULAR SIMULATION AND PHASE EQUILIBRIUM FOR REMOVING DMDS IN MTBE BY EXTRACTIVE DISTILLATION

Abstract

Abstract: The polarizable continuum model (PCM) calculation was used to explore the interaction between extractant and sulfide. In addition, Ellis equilibrium distillation experiments were performed for measuring the vapor-liquid equilibrium data of sulfide dimethyl disulfide (DMDS) in methyl tert-butyl ether (MTBE) and various extractants solutions. At the same time, the basic properties of extractants were measured and compared for screening the optimal solvent. The results of quantitative calculation indicate the following order of the interactions between different extractants and DMDS: dimethyl sulfoxide (DMSO) > sulfolane (SULF) > dimethyl formamide (DMF) > N-methyl-2-pyrrolidone (NMP) > diethylene glycol (DEG). The Ellis distillation experiments show the selectivity order of various extractants as: DMSO > SULF > DMF > NMP > DEG. The molecular simulation results are consistent with the experimental findings. As a result, DMSO can be considered a suitable solvent for MTBE extractive distillation desulfurization. Furthermore, an empirical correlation was built to reveal the equilibrium behaviors under different ratios of extractant/MTBE. This study can provide the necessary data and lay a theoretical foundation for the design and development of MTBE extractive distillation desulfurization process.

Key words: methyl tert-butyl ether, dimethyl disulfide, extractant, desulfurization, molecular simulation

CLC Number:

References

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