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Functionalized porous carbons are central to various important applications such as energy storage and conversion. Here, a simple synthetic route to prepare oxygen‐rich carbon nitrides (CNOs) decorated with stable Ni and Fe‐nanosites is demonstrated. The CNOs are prepared via a salt templating method using ribose and adenine as precursors and CaCl2·2H2O as a template. The formation of supramolecular eutectic complexes between CaCl2·2H2O and ribose at relatively low temperatures facilitates the formation of a homogeneous starting mixture, promotes the condensation of ribose through the dehydrating effect of CaCl2·2H2O to covalent frameworks, and finally generates homogeneous CNOs. As a specific of the recipe, the condensation of the precursors at higher temperatures and the removal of water promotes the recrystallization of CaCl2 (T < Tm = 772 °C), which then acts as a hard porogen. Due to salt catalysis, CNOs with oxygen and nitrogen contents as high as 12 and 20 wt%, respectively, can be obtained, while heteroatom content stayed about unchanged even at higher temperatures of synthesis, pointing to the extraordinarily high stability of the materials. After decorating Ni and Fe‐nanosites onto the CNOs, the materials exhibit high activity and stability for electrochemical oxygen evolution reaction with an overpotential of 351 mV. [ABSTRACT FROM AUTHOR]

During the last decades, many efforts have been devoted to the adaptation of sample preparation techniques and methods to the principles of Green Analytical Chemistry. Among them, this article review focusses on those aimed to green the solvents involved in sample treatment. Research in this field started in the late 1990s with the synthesis of room temperature ionic liquids, which were later replaced by the deep eutectic solvents (DESs). During the last years, a subclass of DESs, the so-called hydrophobic deep eutectic solvents (HDESs) have attracted attention. HDESs have contributed to circumventing some of the limitations of early-synthesised hydrophilic DESs regarding the cost of raw materials, the simplicity of synthesis, and the biocompatibility and, apparently, the biodegradability of the mixtures. In addition, these mixtures allowed the treatment of aqueous samples and the extraction of non-polar analytes. This article discusses fundamental aspects regarding the nomenclature used concerning HDESs, summarises the main physicochemical properties of these mixtures, and through discussion of key application studies, describes current progress in the use of these green solvents for the extraction of trace organic contaminants from a variety of matrices. Remaining gaps and possible lines of future development in this emerging, active and attractive research area are also identified and critically discussed. [Display omitted] • Current use of hydrophobic (deep) eutectic solvents for sample preparation reviewed. • Applications dealing with the determination of organic pollutants are discussed. • A critical overview of the several methodologies in use is provided. • Remaining issues and possible future developments are identified. [ABSTRACT FROM AUTHOR]

Summary: In the present work, we describe the chemical synthesis of 3‐HFAs as prominent derivatives of fatty acids and assess if they could be applied as phase change materials (PCM). In addition, 3‐HFAs were obtained by depolymerization of a bacterial biopolymeric material, polyhydroxyalkanoate. Thermal properties of 3‐hydoxyoctanoic, decanoic, and dodecanoic acids are reported for the first time. These materials showed the potential to be applied as PCM in temperature range from 33°C to 66°C. In order to expand the temperature range for application of 3‐HFAs as PCM, eutectic mass ratios of three kinds of binary mixtures of 3‐HFAs were calculated, and their properties were predicted using the Schröder‐van Laar equation. Thermal properties of these mixtures were validated by differential scanning calorimetry (DSC) analysis. These results showed that eutectics considerably expanded the scope of applications of 3‐HFAs as PCMs. 3‐HFAs originating from biotechnologically obtained polyhydroxyalkanoates also showed potential to be applied in development of PCMs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthesis and characterisation of new N -alkylisoquinolinium bromides. • Determined solid–liquid phase diagrams of isoquinolinium ILs with α,ω -alkanediols. • Discovery of supramolecular self-organisation phenomena leading to interesting co-crystalline IL/ α,ω -diol structures. • Designation and examination of eutectic mixtures as promising eutectic PCMs. • Conclusions drawn from the structure – property relationship: the effect of aliphatic chain length of IL and α,ω -diol. This research focuses on ionic liquids (ILs), specifically N -alkylisoquinolinium bromides with various chain lengths: octyl, decyl, dodecyl, and hexadecyl. The study covers the synthesis and thermophysical characterisation of these compounds, as well as crystal structure determination for all excluding N -decylisoquinolinium bromide ([i-QuinC 10 ][Br]). The obtained thermophysical parameters were compared with the literature data and also within the extended homologous series. The solid–liquid phase equilibria (SLE) in mixtures of ILs with certain α,ω -alkanediols (1,6-hexanediol, 1,8-octanediol, 1,10-decanediol, 1,12-dodecanediol) were investigated. As a result of SLE studies, eutectic mixtures capable of acting as eutectic phase-change materials - ePCMs - were determined. Additionally, a self-organization phenomenon was observed between specific pairs, leading to the formation of co-crystals (solid-complex phase). All binary mixtures with [i-QuinC 8 ][Br] formed a simple eutectic system, while in the case of [i-QuinC 10 ][Br], the formation of a non-congruent melting compound was observed in the systems with 1,8-octanediol and 1,10-decanediol. Among the systems with [i-QuinC 12 ][Br], congruent melting compounds were observed for mixtures with 1,8-octanediol, 1,10-decanediol and 1,12-dodecanediol, while a simple eutectic was recorded for 1,6-hexanediol. IL [i-QuinC 16 ][Br] co-crystalised only with 1,12-dodecanediol, while with other diols formed simple eutectic systems. Calorimetric analysis (DSC) and crystal structure determination (X-ray diffraction) were used to characterize the obtained supramolecular compounds. As a result, a series of ePCMs with melting points ranging from 295 K to 343 K are presented, with the {[i-QuinC 12 ][Br] + 1,10-decanediol} system showing the highest enthalpy of melting (173.5 J·g−1). The found features and correlations between structure and properties imply the necessity for additional investigation, indicating the potential for a new generation of compounds with customizable physicochemical properties. [ABSTRACT FROM AUTHOR]

The applications of eutectic systems, including deep eutectic solvents (DESs), in diverse sectors have drawn significant interest from researchers, academicians, engineers, medical scientists, and pharmacists. Eutecticity increases drug dissolution, improves drug penetration, and acts as a synthesis route for drug carriers. To date, DESs have been extensively explored as potential drug delivery systems on account of their unique properties such as tunability and chemical and thermal stability. This review discusses two major topics: first, the application of eutectic mixtures (before and after the introduction of DES) in the field of drug delivery systems, and second, the most promising examples of DES pharmaceutical activity. It also considers future prospects in the medical and biotechnological fields. In addition to the application of DESs in drug delivery systems, they show greatly promising pharmaceutical activities, including anti-fungal, anti-bacterial, anti-viral, and anti-cancer activities. Eutecticity is a valid strategy for overcoming many obstacles inherently associated with either introducing new drugs or enhancing drug delivery systems. [ABSTRACT FROM AUTHOR]

A stricter definition of a deep eutectic solvent (DES) is urgent, so that it may become a sound basis for further developments in this field. This communication aims at contributing to deepening the understanding of eutectic and deep eutectic mixtures concerning their definition, thermodynamic nature and modelling. The glut of literature on DES applications should be followed by a similar effort to address the fundamental questions on their nature. This hopefully would contribute to correct some widespread misconceptions, and help to establish a stringent definition of what a DES is. DES are eutectic mixtures for which the eutectic point temperature should be lower to that of an ideal liquid mixture. To identify and characterize them, their phase diagrams should be known, in order to compare the real temperature depression to that predicted if ideality is assumed, and to define composition ranges for which they are in the liquid state at operating temperatures. It is also shown that hydrogen bonding between the DES components should not be used to define or characterize a DES, since this would describe many ideal mixtures. The future of deep eutectic solvents is quite promising, and we expect that this work will contribute to the efficient design and selection of the best DES for a given application, and to model properties and phase equilibria without which the process design is impractical. [ABSTRACT FROM AUTHOR]

Deep eutectic solvents (DESs) consist of a mixture of two or more solid components, which gives rise to a lower melting point compared to the starting materials. Until recently only hydrophilic DESs were available, and despite their revolutionary role in the alternative‐solvents field, important issues in chemistry, and chemical engineering (such as water‐related problems and the replacement of toxic volatile organic compounds) could not be tackled. Hydrophobic (deep)—here in parenthesis due to the different depths of the eutectic melting points—eutectic solvents are a subclass of DESs where both components are hydrophobic. The low toxicity, high biodegradability, and straightforward preparation without further purification steps of naturally occurring low‐cost compounds are among the key advantages. Although research on hydrophobic DESs is scarce (the first report was only published in 2015), some interesting features and applications have been reported and deserve to be evaluated and comparisons established. This Minireview is divided into two parts: The first part provides a brief general introduction to DESs and the second part discusses the nomenclature using solid–liquid phase diagram analysis, chemical stability, thermophysical properties comparison, and finally the most important emerging fields of application. [ABSTRACT FROM AUTHOR]

Abstract Deep eutectic solvents (DESs) have been widely recognized as ionic liquids (ILs) analogues due to their low production cost and superior favorable properties over conventional ILs. Studying the physical properties of these solvents will contribute to design processes involving DESs. In this study, five DESs have been successfully prepared using ethylene glycol (EG) as hydrogen bond donor (HBD) with N , N ‑diethylethanolammonium chloride (DAC), benzyltriphenylphosphonium chloride (BTPC), choline chloride (ChCl), methyltriphenylphosphonium bromide (MTPB) and tetra‑ n ‑butylammonium bromide (TBAB) as salts. The freezing point of each of the five studied DESs was measured using Differential Scanning Calorimetry (DSC) and the DES functional groups were identified using the Fourier transform infrared (FTIR) spectroscopy. Moreover, the viscosity, density, electrical conductivity and surface tension were measured at a temperature range of 293.15–353.15 K and they were highly affected by the variation of the temperature. It is worth mentioning that the studied DESs showed many physical characteristics similar to that of ILs, which boost their possibilities to be employed in interdisciplinary domains. Graphical abstract Unlabelled Image Highlights • Ethylene glycol based deep eutectic solvents (DESs) were prepared from different salts. • The ratios of salt to HBD were selected based on homogeneity and stability of the DES. • The studied DESs showed physical properties similar to that of ionic liquids. • FTIR analysis depicted the existence of new functional groups in DES structure. [ABSTRACT FROM AUTHOR]

The field of industrial biotechnology is rapidly growing. This includes the use of biosynthesis of the fragrance-row materials in chemical industry, food industry, cosmetical and pharmaceutical industry. The production of 2-phenylethanol (PEA), which is an important flavor and fragrance compound, with a rose-like odor has been significantly increased last decade. The ionic liquids (ILs) and binary eutectic mixtures (EM) are proposed as an entrainers for the extraction of PEA in a biphasic biosynthesis. ILs and DES reveal many unique properties which make them very interesting for applications in modern ‘green’ technologies. In this work we present new experimental results on (solid, or liquid + liquid) phase equilibrium (SLE/LLE) measurements of twelve binary systems composed of pyrrolidinium-based ILs (namely: 1-butyl-1-methylpyrrolidinium chloride, [BMPYR][Cl] and 1-butyl-1-methylpyrrolidinium bis{(trifluoromethyl)sulfonyl}imide [BMPYR][NTf 2 ] as well as 1-hexyl-1-methylpyrrolidinium chloride, [HMPYR][Cl] and 1-hexyl-1-methylpyrrolidinium bis{(trifluoromethyl)sulfonyl}imide [HMPYR][NTf 2 ] with alcohols (1-decanol, 2-methyl-1-butanol, 2-methyl-2-butanol) and oleic acid. Additionally, three ternary LLE mixtures are presented {IL, or EM + PEA + water} at T = 308.15 K and ambient pressure. The data reveals that [HMPYR][NTf 2 ] ionic liquid is more attractive than [BMPYR][NTf 2 ] and that EMs ([BMPYR][NTf 2 ] + 2-methyl-2-butanol) and ([HMPYR][NTf 2 ] + 2-methyl-2-butanol) present worst selectivities and solute distribution ratios than those observed for pure ILs. However, they may be assumed as an alternative, less cost solvents for the separation of PEA from the water phase using liquid-liquid extraction at ambient conditions. [ABSTRACT FROM AUTHOR]

In recent years, ionic liquids and deep eutectic mixtures have demonstrated great potential in extraction processes relevant to several scientific and technological activities. This review focuses on the applicability of these sustainable solvents in a variety of extraction techniques, including but not limited to liquid- and solid-phase (micro) extraction, microwave-assisted extraction, ultrasound-assisted extraction and pressurized liquid extraction. Selected applications of ionic liquids and deep eutectic mixtures on analytical method development, removal of environmental pollutants, selective isolation, and recovery of target compounds, purification of fuels, and azeotrope breaking are described and discussed. [ABSTRACT FROM AUTHOR]

Carbonaceous materials have been extensively used in diverse areas because of facile, low-cost, environmentally friendly, and nontoxic routes to produce novel functional materials that can be commercialized in the near future. Interestingly, from the past few decades, the ever-growing demand for advanced functional materials for various application has triggered intensive research efforts on solvothermal carbon (STCs). There have been several reviews published involving preparation of hydrothermal carbon (HTCs) using variety of ingredients for several application. However, review focusing on STCs is uncommon. Hence, this review article provides an overview on the advances and latest trends in solvothermal carbonization synthesized using ionic liquids (ILs), deep eutectic solvents (DES), and eutectic salts used as feedstock and/or solvents. Further, present review deals with a particular focus on the carbon formation mechanism with unique properties, perspectives on large scale production, advantages over conventional HTCs, and their applications in energy storage, water purification and catalysis. This is the sole review deliberating spectacular strategies of preparing advanced carbon materials in view of solvothermal carbonization. [ABSTRACT FROM AUTHOR]

This paper is focused on preparation and performance analysis of a series of form-stable phase change materials (FSPCMs), based on eutectic mixtures as phase change materials (PCMs) for thermal energy storage and high-density polyethylene (HDPE)-ethylene-vinyl acetate (EVA) polymer as supporting materials. The PCMs were eutectic mixtures of tetradecanol (TD)--capric acid (CA), TD--lauric acid (LA), and TD--myristic acid (MA), which were rarely explored before. Thermal properties of eutectic mixtures and FSPCMs were measured by differential scanning calorimeter (DSC). The onset melting/solidification temperatures of form-stable PCMs were 19.13 °C/13.32 °C (FS TD--CA PCM), 24.53 °C/24.92 °C (FS TD-LA PCM), and 33.15 °C/30.72 °C (FS TD-MA PCM), respectively, and latent heats were almost greater than 90 J/g. The surface morphologies and chemical stability of form-stable PCM were surveyed by scanning electron microscopy (SEM) and Fourier-transform infrared (FT-IR) spectroscopy, respectively. The thermal cycling test revealed that the thermal reliability of these three form-stable PCMs was good. Thermal storage/release experiment indicated melting/solidification time was shortened by introducing 10 wt % aluminum powder (AP). It is concluded that these FSPCMs can act as potential building thermal storage materials in terms of their satisfactory thermal properties. [ABSTRACT FROM AUTHOR]

The physico-chemical characteristics of blends of palm olein and palm kernel oil which were further modified by chemical interesterification were studied. The slip melting points of non-interesterified blends were 19.7, 16.2, 14.5, 14.5 and 14.4 °C while those of the chemically interesterified blends were 17.7, 16.2, 19.8, 18.7 and 18.7 °C at 40, 30, 20, 10 and 0% palm kernel oil, respectively. Chemical interesterification lowered the solid fat content of the pure samples and blends across different temperatures except 90% palm olein at 15 °C where the solid fat content was higher than for non-interesterified samples. Palm kernel oil, palm olein and their blends before and after chemical interesterification, crystallized mainly in the β′ form. However, chemical interesterification modified the microstructure from a combination of fat particles with void regions of crystalline materials to fat particles without regions of void crystalline materials. Palm olein and palm kernel oil blends are mainly used for food preparation in Nigeria. This study has shown that there are no significant differences in the physical and chemical properties of non-chemically interesterified and chemically interesterified blends of palm olein and palm kernel oil. This implies that blending of palm olein and palm kernel oil without chemical interesterification can provide the fluidity desirable at ambient temperatures for food applications in the tropics. [ABSTRACT FROM AUTHOR]

Abstract: The lidocaine–salol binary system has been investigated by differential scanning calorimetry, direct visual observations, and X-ray powder diffraction, resulting in a temperature-composition phase diagram with a eutectic equilibrium. The eutectic mixture, found at 0.423±0.007 lidocaine mole-fraction, melts at 18.2±0.5°C with an enthalpy of 17.3±0.5kJmol−1. This indicates that the liquid phase around the eutectic composition is stable at room temperature. Moreover, the undercooled liquid mixture does not easily crystallize. The present binary mixture exhibits eutectic behavior similar to the prilocaine–lidocaine mixture in the widely used EMLA® topical anesthetic preparation. [Copyright &y& Elsevier]

We have designed, synthesized, and evaluated the physical properties of some high birefringence (Δn) isothiocyanato biphenyl-tolane liquid crystals. These compounds exhibit Δn ∼ 0.48-0.52 at room temperature and wavelength λ = 633 nm. Laterally substituted short alkyl chains and fluorine atom eliminate smectic phase and lower the melting temperature. The moderate melting temperature and very high clearing temperature make those compounds attractive for eutectic mixture formulation. A eutectic mixture based on those compounds was formulated and its physical properties evaluated. [ABSTRACT FROM AUTHOR]

• Measurement of solvation interactions for deep eutectic solvents (DESs) is discussed. • DES solvation power varies with hydrogen bond acceptor (HBA)/hydrogen bond donor (HBD) ratio. • Inverse gas chromatography is sensitive to measure small variations in HBA/HBD ratio. • Eighteen eutectic mixtures of varied HBA and HBD composition are examined. • Hydrogen bond basicity is impacted the most when HBA/HBD ratio is varied. Deep eutectic solvents (DESs) have gained increasing popularity in separation science due to the fact that their physico-chemical properties can be easily fine-tuned by varying the type or ratio of hydrogen bond acceptor (HBA) and hydrogen bond donor (HBD). While it is well-known that the molar ratio of HBA/HBD affects the melting point of a eutectic mixture, much less is understood regarding its effect on the magnitude of individual solvation interactions. This is largely due to the fact that established solvatochromic dye methods lack sensitivity when the HBA/HBD ratio is varied slightly in a eutectic mixture. Herein, this study is the first to measure the variation of DES solvation interactions with small changes in the molar ratio of HBA/HBD using inverse gas chromatography (IGC). Solute-solvent interactions of three different DES systems comprised of ammonium salts and organic acids were examined. The probe molecules were studied for 18 eutectic mixtures of varied HBA and HBD composition. DES hydrogen bond basicity, hydrogen bond acidity, and dispersive-type interactions exhibited the greatest change when the molar ratio of HBA/HBD was varied in the eutectic mixture. Results from this study demonstrate that the HBA/HBD ratio can be used to modulate the solvation characteristics for this class of DESs in separations and that the stoichiometric ratio of the HBA/HBD is important in ensuring their reproducible preparation. [ABSTRACT FROM AUTHOR]

Eutectic systems offer a wide range of new (green) designer solvents for diverse applications. However, due to the large pool of possible compounds, selecting compounds that form eutectic systems is not straightforward. In this study, a simple approach for preselecting possible candidates from a pool of substances sharing the same chemical functionality was presented. First, the melting entropy of single compounds was correlated with their molecular structure to calculate their melting enthalpy. Subsequently, the eutectic temperature of the screened binary systems was qualitatively predicted, and the systems were ordered according to the depth of the eutectic temperature. The approach was demonstrated for six hydrophobic eutectic systems composed of L-menthol and monocarboxylic acids with linear and cyclic structures. It was found that the melting entropy of compounds sharing the same functionality could be well correlated with their molecular structures. As a result, when the two acids had a similar melting temperature, the melting enthalpy of a rigid acid was found to be lower than that of a flexible acid. It was demonstrated that compounds with more rigid molecular structures could form deeper eutectics. The proposed approach could decrease the experimental efforts required to design deep eutectic solvents, particularly when the melting enthalpy of pure components is not available. [ABSTRACT FROM AUTHOR]

Lovastatin (LOV) is a drug used to treat hypercholesterolemia. Recent studies have identified its antioxidant effects and potential use in the treatment of some types of cancer. However, the low bioavailability related to its poor water solubility limits its use in solid oral dosage forms. Therefore, to improve the solubility of LOV three eutectic systems of LOV with the carboxylic acids benzoic (BEN), salicylic (SAL) and cinnamic (CIN) were obtained. Both binary phase and Tammann diagrams were constructed using differential scanning calorimetry (DSC) data of mixtures prepared from 0.1 to 1.0 molar ratios. Binary mixtures and eutectics were prepared by liquid-assisted grinding. The eutectics were further characterized by DSC and powder X-ray diffraction (PXRD), Fourier-transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). The LOV-BEN, LOV-SAL and LOV-CIN system formed a eutectic at an LOV mole fraction of 0.19, 0.60 and 0.14, respectively. The systems exhibited improvements in LOV solubility, becoming more soluble by five-fold in the LOV-SAL system and approximately four-fold in the other two systems. Considering that the solubility enhancements and the carboxylic acids used are generally recognized as safe by the U.S. Food and Drug Administration (FDA), the LOV eutectic systems are promising materials to be used in a solubility enhancement strategy for pharmaceutical product formulation. [ABSTRACT FROM AUTHOR]