Search Results (3)

Wheat bran (WB) is a very abundant residual biomass, resulting from wheat processing. Although it can be used as feed without further processing, the utilization of WB as a bioresource of high valued-added chemicals would require task-specific treatments. In this context, the present work aimed to used two newly reported deep eutectic solvents (DESs) for the effective organosolv treatment of WB to achieve a high-performance polyphenol recovery. One of the DESs used was alkaline, composed of glycerol and sodium carbonate (GL-SCar), and the other one was acidic, composed of glycerol and oxalic acid (GL-OA), and the treatments carried out were evaluated based on severity. Further optimization with a response surface methodology showed that treatment with GL-SCar could afford a maximum total polyphenol yield of 24.30 ± 2.34 mg ferulic acid equivalents per g of dry WB mass, the optimal settings being t = 172 min and T = 90 °C. Likewise, the GL-OA treatment yielded 23.21 ± 3.82 mg ferulic acid equivalents per g of dry WB mass, with the corresponding optimal conditions being t = 180 min and T = 90 °C. The examination of the polyphenolic profile of the extracts obtained revealed important differences in the composition, as the extract obtained with GL-SCar treatment was dominated by ferulic acid, whereas the extract produced with GL-OA treatment was enriched in a ferulate derivative, previously identified as a ferulate pentose ester. However, both treatments were shown to liberate only part of the bound phenolics, as judged by comparison with a reference alkaline hydrolysis. The difference in composition most probably defined the antioxidant effects of the extracts, with the GL-OA extract displaying more powerful antiradical and ferric-reducing power activity, despite the significantly lower polyphenolic concentration. The evidence that emerged from this investigation pointed to both DESs as solvents with high potency in polyphenol recovery from WB, yet further improvements are required to maximize yield. Moreover, it was shown that, due to their different nature (alkaline/acidic), both DESs could be suitably tuned for delivering extracts enriched in different phytochemicals. Full article

This study employs Density Functional Theory (DFT) calculations and traditional all-atom Molecular Dynamics (MD) simulations to reveal atomistic insights into a task-specific Deep Eutectic Solvent (DES) supported by graphene oxide with the aim of mimicking its application in the natural gas desulfurization process. The DES, composed of N,N,N′,N′-tetramthyl-1,6-hexane diamine acetate (TMHDAAc) and methyldiethanolamine (MDEA) supported by graphene oxide, demonstrates improved efficiency in removing hydrogen sulfide from methane. Optimized structure and HOMO-LUMO orbital analyses reveal the distinct spatial arrangements and interactions between hydrogen sulfide, methane, and DES components, highlighting the efficacy of the DES in facilitating the separation of hydrogen sulfide from methane through DFT calculations. The radial distribution function (RDF) and interaction energies, as determined by traditional all-atom MD simulations, provide insights into the specificity and strength of the interactions between the DES components supported by graphene oxide and hydrogen sulfide. Importantly, the stability of the DES structure supported by graphene oxide is maintained after mixing with the fuel, ensuring its robustness and suitability for prolonged desulfurization processes, as evidenced by traditional all-atom MD simulation results. These findings offer crucial insights into the molecular-level mechanisms underlying the desulfurization of natural gas, guiding the design and optimization of task-specific DESs supported by graphene oxide for sustainable and efficient natural gas purification. Full article

Ionic liquids (ILs) and deep eutectic solvents (DESs) have proven to be suitable solvents and reactants for low-temperature reactions. To date, several attempts were made to apply this promising class of materials to metal oxide chemistry, which, conventionally, is performed at high temperatures. This review gives an overview about the scientific approaches of the synthesis as well as the dissolution of metal oxides in ILs and DESs. A wide range of metal oxides along with numerous ILs and DESs are covered by this research. With ILs and DESs being involved, many metal oxide phases as well as different particle morphologies were obtained by means of relatively simple reactions paths. By the development of acidic task-specific ILs and DESs, even difficultly soluble metal oxides were dissolved and, hence, made accessible for downstream chemistry. Especially the role of ILs in these reactions is in the focus of discussion. Full article