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The accurate design of a packed column is largely dependent upon the accurate calculation of the effective mass transfer area (ae ) of a packing. The experimental and the modelling study for the packed column with CO2-Monoethanolamine (MEA) system has been reported by employing Sulzer DX packing. The model validation results revealed that the modification in the available simple ae correlations is necessary to attain the reliable results using Sulzer DX packing. Recently, a new simple ae correlation suitable for Sulzer DX packing with MEA-CO2 system has been reported. Therefore, in the present study, the rate-based model is developed using the newly developed ae correlation for the packed absorption column with Sulzer DX structured packing for CO2-MEA system. The model has been successfully validated with the experimental data. Overall results depict good accuracy (AAD < 15%) of predicted CO2 concentration profiles due to the reliable ae calculations. However, the relative accuracy is low at high liquid flowrates (> 8 m3/m2h) due to the design limitations of the ae correlation. Therefore, in this study, the adopted ae mass transfer correlation is found suitable for the reliable modelling of the packed absorption column with Sulzer DX packing.

In the article titled “VLE of Carbon Dioxide-Loaded Aqueous Potassium Salt of L-Histidine Solutions as a Green Solvent for Carbon Dioxide Capture: Experimental Data and Modelling” [1], the second author was mistakenly linked to the third affiliation. %e corrected authors’ list and affiliations are shown above.

In this study, vapour-liquid equilibrium of CO2-loaded aqueous potassium salt of L-histidine was studied for a wide range of temperature (313.15-353.15 K), pressure (150-4000 kPa), and solvent concentrations (1-2.5 molar). The experimental results show that L-histidine has an excellent absorptive capacity for carbon dioxide. When compared to conventional solvent (monoethanolamine) and amino acid salt (potassium L-lysinate) at similar process conditions, L-histidine has superior absorption capacity. Moreover, modified Kent-Eisenberg model was used to correlate the VLE of the studied system with excellent agreement between the model and experimental values. The model exhibited an AARE% of 7.87%, which shows that it can satisfactorily predict carbon dioxide solubilities in aqueous potassium salt of L-histidine at other process conditions. Being a biological component in origin, almost negligibly volatile, and highly resistant to oxidative degradation, L-histidine offers certain operational advantages over other solvents used and has a promising potential for carbon dioxide capture.

The polycarbonate membranes performances are improved by the incorporation of silica nanoparticles into the polymer matrix. Prepared PC/silica nanocomposite membranes with various silica content are considered and the experimental relative permeance of CO2 gas at 200 kPa (2 bar) feed pressure are used as reference in the predictions using the existing theoretical models such as Maxwell-Wagner-Sillar, Bruggeman, Lewis-Nielsen, Pal, and modified Pal models. TEM and BET analysis were used to characterize the silica nanoparticles; FESEM was used to characterize the morphology of the nanocomposite membranes. The TEM image of the silica nanoparticles reveals that the nanoparticles are mostly spherical. BET results reveal that the surface area and pore diameter of the silica nanoparticles are 618.8 m2/g and 0.28 nm, respectively. The existing models have resulted in poor predictions with errors AARE % of 26.52 to 28.02 %. Observation by FESEM image shows that the dispersed particles are surrounded by interfacial voids and rigidified polymer layer. Modified Bruggeman models that consider the interfacial volume show appreciable prediction with AARE 4.59 % being obtained with the pseudo-two-phase Bruggeman model. Moreover, when the model considered pseudo-three-phase morphology, the AARE % value reduced to 3.92 %. Thus, the contribution due to the interfacial rigidified layer was minimal.

Polycarbonate/silica nanocomposite membranes at low silica loading were fabricated by solution blending and solvent evaporation technique. The functionalized silica nanoparticles used were synthesized by co-condensing hydrolyzed tetraethylorthosilicate with 3-aminopropyl trimethoxysilane in the sol–gel process. The membranes morphology, composition, surface, structure, thermal and mechanical properties were analyzed by the standard characterization techniques. The gas permeation tests were conducted in four-channel permeation cells. Field emission scanning electron microscopy results reveal that membranes above 3 wt % silica content formed distinguishable voids and agglomerates. Fair distribution of silica nanoparticles and absence of residual solvents were observed by energy dispersive X-ray and thermogravimetric analysis. Fourier transform infrared spectroscopy spectra confirmed the presence of new functional groups (NH) and (OH) bonds. The X-ray diffraction pattern revealed the polymer-particle interactions, the formation of rigidified polymer chain, and nanostructured silicon crystals. Further, the thermogravimetric analysis results revealed thermal stability enhancement while differential scanning calorimetry results of increased glass transition temperatures confirmed the presence of rigidified polymer chain. Furthermore, enhancements in mechanical strength of the membranes were observed. Moreover, at all feed pressures, increased CO2, N2, and CH4 gas permeation was observed. At 6 bar feed pressure, the CO2/N2 and CO2/CH4 ideal selectivities of PC membranes with 3 wt % silica loading have increased from 19.2 to 38.0 and 29.2, respectively. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45310.