Distillation is one of the most widely used separation unit operations in process industries, although it is quite energy intensive. In many cases, the enormous energy requirements for distillation make it economically infeasible to carry out the separation. Thermally coupled distillation system (TCDS) is an advanced distillation method that provides significant energy savings of about 30% as compared with conventional distillation column sequences. The most well-known TCDS sequence, the Petlyuk configuration, has some operational challenges due to bidirectional vapour flow, which makes its implementation difficult in two-column mode. To overcome these limitations, a number of unidirectional vapour flow configurations have been proposed in the literature. The work on simulation analysis for such configurations is limited. In this paper, simulation models for two such configurations are developed, analyzed and compared with the Petlyuk and conventional distillation column sequences for separation of equimolar mixture of benzene-toluene-ethylbenzene.

The main aim of the present investigation was to elucidate the efficacy of silver ion chromatography for selective separation of unsaturated (oleic, linoleic, and linolenic) fatty acids on a preparative scale. Accordingly, the present work was predominantly divided into two parts. In the first part, adsorption of oleic acid was carried out using commercially available ion exchange resins and silver-ion-loaded resins (R-Ag+) prepared in the laboratory from nonpolar and polar solvents in a batch mode. The maximum adsorption of oleic acid was found on R-Ag+ (454.55 g·kg–1) compared with other commercially available ion exchange resins from heptane at ambient temperature (303 K). The effect of temperature on the adsorption of oleic acid on R-Ag+ from heptane was investigated at 303, 313, and 323 K. The adsorption of oleic acid was favored at 303 K and decreased with a further increase in temperature. Experimental batch equilibrium data were modeled using the Langmuir and Freundlich isotherms. Further, thermodynamic parameters viz., ΔGads 0, ΔHads 0, and ΔSads 0, were estimated. The negative values of ΔGads 0 and ΔHads 0 show that the adsorption of oleic acid on R-Ag+ was spontaneous and exothermic in nature. Based on the results obtained in the first part, the R-Ag+ resin was subjected to adsorption of fatty acids from industrial fatty acids mixture using heptane as a solvent at 303 K. A multicomponent Freundlich isotherm was used to model experimental batch equilibrium data. Linolenic acid and linoleic acid were preferentially adsorbed over oleic acid with selectivities of 1.40 and 1.16, respectively, from industrial fatty acids mixture.

Energy conservation, utilization, and effective integration are of utmost importance for future sustenance. Accordingly, this work focuses on the generation of power from the low-grade temperature below 150 C. A proposed novel multi-composition ammonia liquor absorption engine (MALAE) power cycle

Liquid phase axial mixing studies have been carried out in the novel solid-liquid circulating fluidized bed (SLCFB). The SLCFB primarily consists of a single multistage column (having an inner diameter of 100 mm i.d. and length of 1.40 m) which is divided into two sections wherein both the steps of utilization, namely loading (e.g., adsorption and catalytic reaction) and regeneration of solid phase, can be carried out simultaneously in continuous mode. Weak base anion exchange resin was used as the solid phase, whereas water as the fluidizing medium. The effects of physical properties of solid phase, superficial liquid velocity, and solid circulation rate on liquid phase axial dispersion coefficient were investigated. The dispersion coefficient increases monotonically with an increase in the size of solid particle, superficial liquid velocity, and solid circulation rate. The axial dispersion model (ADM) was used to model experimental residence time distribution (RTD) data. A good agreement was found between ADM predictions and the experimental measurements. A unified correlation has also been proposed to determine dispersion coefficient as a function of physical properties of solid and liquid phases, superficial liquid velocity, and solid circulation rate based on all previous and present experimental data on multistage SLCFB.

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