Search

The use of deep eutectic solvents (DESs) for the preparation of polymer membranes for environmental separation technologies is comprehensively reviewed. DESs have been divided into five categories based on the hydrogen bond donor (HBD) and acceptor (HBA) that are involved in the production of the DESs, and a wide range of DESs' physicochemical characteristics, such as density, surface tension, viscosity, and melting temperature, are initially gathered. Furthermore, the most popular techniques for creating membranes have been demonstrated and discussed, with a focus on the non-solvent induced phase separation (NIPS) method. Additionally, a number of studies have been reported in which DESs were employed as pore formers, solvents, additives, or co-solvents, among other applications. The addition of DESs to the manufacturing process increased the presence of finger-like structures and macrovoids in the cross-section and, on numerous occasions, had a substantial impact on the overall porosity and pore size. Performance data were also gathered for membranes made for various separation technologies, such as ultrafiltration (UF) and nanofiltration (NF). Lastly, DESs provide various options for the functionalization of membranes, such as the creation of various liquid membrane types, with special focus on supported liquid membranes (SLMs) for decarbonization technologies, discussed in terms of permeability and selectivity of several gases, including CO2, N2, and CH4. [ABSTRACT FROM AUTHOR]

Poly(ethylene terephthalate) (PET) waste accumulation poses significant environmental challenges due to its persistent nature and current management limitations. This study explores the effectiveness of imidazolium-based neoteric solvents [Emim][OAc] and [Bmim][OAc] as catalytic co-solvents in the glycolysis of PET with ethylene glycol (EG). Reaction thermal kinetics showed that both ionic liquids (ILs) significantly enhanced the depolymerization rate of PET compared to traditional methods. The use of [Emim][OAc] offered a lower activation energy of 88.69 kJ·mol−1, thus making the process more energy-efficient. The contribution of key process parameters, including temperature (T), plastic-to-ionic liquid (P/IL) mass ratio, and plastic-to-solvent (P/S) mass ratio, were evaluated by means of a factorial analysis and optimized to achieve the maximum PET conversion for both neoteric solvents. The relevance sequence for both ionic liquids involved the linear factors T and P/S, followed by the interaction factors T×P/S and T×P/IL, with P/IL being the less significant parameter. The optimal conditions, with a predicted conversion of 100%, involved a temperature of 190 °C, with a P/IL of 1:1 and a P/S of 1:2.5, regardless of the IL used as the catalytic co-solvent. [ABSTRACT FROM AUTHOR]

Silk sericin (SS)–based hydrogels show promise for wound healing due to their biocompatibility, moisture regulation, and cell proliferation properties. However, there is still a need to develop green crosslinking methods to obtain non-toxic, absorbent, and mechanically strong SS hydrogels. This study investigated the effects of three green crosslinking methods, annealing treatment (T), exposure to an absolute ethanol vapor atmosphere (V.E), and water vapor (V.A), on the physicochemical and mechanical properties of SS and poly (vinyl alcohol) (PVA) biohydrogels. X-ray diffraction and Fourier-transform infrared spectroscopy were used to determine chemical structures. Thermal properties and morphological changes were studied through thermogravimetric analysis and scanning electron microscopy, respectively. The water absorption capacity, mass loss, sericin release in phosphate-buffered saline (PBS), and compressive strength were also evaluated. The results showed that physical crosslinking methods induced different structural transitions in the biohydrogels, impacting their mechanical properties. In particular, V.A hydrogen presented the highest compressive strength at 80% deformation owing to its compact and porous structure with crystallization and bonding sites. Moreover, both the V.A and T hydrogels exhibited improved absorption capacity, stability, and slow SS release in PBS. These results demonstrate the potential of green physical crosslinking techniques for producing SS/PVA biomaterials for wound healing applications. [ABSTRACT FROM AUTHOR]

In this work, the experimental liquid-liquid equilibria (LLE) data of 2-methyl-2-butanol + 1,2,3-propanetriol (glycerol) + water and 2-butanol + 1,2,3-propanetriol (glycerol) + water systems at different temperatures are presented. The LLE of the systems has been measured between 283 and 323 K. The NRTL and UNIQUAC models were applied to the ternary systems. The interaction parameters obtained from both models successfully correlated the equilibrium compositions. The experimental tie lines were compared to the values predicted by the UNIFAC method. Finally, the solvent capability of both alcohols was checked in order to separate the mixture formed by glycerol and water. [ABSTRACT FROM AUTHOR]

Abstract: In this work, experimental liquid–liquid equilibria data of the systems 4-methyl-2-pentanone+ethanol+water and 4-methyl-2-pentanone+ n-butanol+water are presented. The liquid–liquid equilibria of both systems have been measured between 283.2 and 323.2K. The NRTL and UNIQUAC models were applied to fit the data for both ternary systems. The interaction parameters obtained from both models successfully correlated the equilibrium compositions. The binodal lines were compared to the values predicted by the UNIFAC-LLE and UNIFAC models. Moreover, the solvent capability of 4-methyl-2-pentanone was checked in order to separate these azeotropic mixtures alcohol+water. [Copyright &y& Elsevier]

Abstract: The present study is devoted to the experimental measurement and thermodynamic modeling of solid carnosic acid solubility in supercritical CO2 +ethanol as a co-solvent. Measurements were carried out at temperatures in the range of 313.15 and 333.15K, pressures ranging from 280 to 400bar, and at different content of the modifier ethanol (from 0.7 to 10%). The Group Contribution Associating Equation of State (GCA-EoS) [H.P. Gros, S.B. Bottini, E.A. Brignole, High pressure phase equilibrium modeling of mixtures containing associating compounds and gases, Fluid Phase Equilibria 139 (1997) 75–87] was applied in this work to represent the experimental solubility data obtained. Due to the lack of information in the literature about pure carnosic acid parameters, its solid volume, critical properties, and sublimation pressures were estimated in this work. The key step in the thermodynamic modeling proved to be the introduction of a solute hard-sphere parameter in the Carnahan–Starling repulsive term of the model, which depends on both temperature and pressure. [Copyright &y& Elsevier]