Optimal Design and Effective Control of Triple-Column Extractive Distillation for Separating Ethyl Acetate/Ethanol/Water with Multiazeotrope

Advancements in Optimization and Control Techniques for Intensifying Processes

Process Intensification (PI) is a vast and growing area in Chemical Engineering, which deals with the enhancement of current technology to enable improved efficiency; energy, cost, and environmental impact reduction; small size; and better integration with the other equipment. Since process intensification results in novel, but complex, systems, it is necessary to rely on optimization and control techniques that can cope with such new processes. Therefore, this review presents some advancements in the field of process intensification that are worthy of exploring in detail in the coming years. At the end, several important open questions that can be taken into consideration in the coming years are listed.

Effect of Water on Phenol Separation from Model Oil with Ionic Liquids Based on COSMO-RS Calculation and Experimental Study

Ionic liquids (ILs) are widely used in the extraction of phenolic compounds from low-temperature coal tar (LTCT). However, both ILs and LTCT contain a certain amount of water. The existence of water may have a remarkable impact on the phenol separation performance of ILs with different structures. In this work, the capacity and selectivity for m-cresol, as well as the solubility of cumene and dodecane in different IL-H2O mixtures, were firstly calculated by the conductor-like screening model for real solvents (COSMO-RS) at infinite dilution. The calculation covers ILs with different anionic and anionic structures and different water contents. To explore the effect of water in IL on separation performance, 1-ethyl-3-methyl imidazolium acetate ([C2mim][Ac]) was selected as the representative IL, and then the molecular interactions between the [C2mim][Ac]-H2O mixture solvent and solute (including m-cresol, cumene, and dodecane) were analyzed by COSMO-RS. The results indicated that both water and m-cresol could form hydrogen bonds with [C2mim][Ac]. The competition between them leads to decreasing separation performance for m-cresol of the [C2mim][Ac]-H2O mixture with increasing water content. Moreover, through analyses of m-cresol extraction efficiency, distribution coefficient, selectivity, and entrainment of cumene and dodecane, the experimental results confirmed that the presence of water in [C2mim][Ac] had a negative effect on the separation of m-cresol. The viscosity and UV-vis spectra of the [C2mim][Ac]-H2O mixture were also measured. Water in ILs should be removed as much as possible to ensure a better dephenolization effect and avoid phenol containing wastewater.