Physicochemical Properties, Cytotoxicity, and Antioxidative Activity of Natural Deep Eutectic Solvents Containing Organic Acid

Natural deep eutectic solvents (NADES) may be considered ‘designer solvents’ due to their numerous structural variations and the possibility of tailoring their physicochemical properties. Prior to their industrial application, characterization of NADES is essential, including determination of their physicochemical properties, cytotoxicity, and antioxidative activity. The most important physicochemical properties of eight prepared NADES (choline chloride:malic acid, proline:malic acid, choline chloride:proline:malic acid, betaine:malic acid, malic acid:glucose, malic acid:glucose:glycerol, choline chloride:citric acid, and betaine:citric acid) were measured as functions of temperature and water content. In general, the structure of prepared NADES greatly influences their physical properties, which could be successfully modified and adjusted by addition of water. All tested NADES were absolutely benign and noncorrosive for investigated steel X6CrNiTi18-10. Furthermore, cytotoxicity of prepared solvents was assessed toward three human cell lines (HEK-293T, HeLa, and MCF-7 cells), and antioxidative activity was measured by the Oxygen Radical Absorbance Capacity (ORAC) method. With regard to cell viability, all tested NADES containing carboxylic acid could be classified as practically harmless and considered environmentally safe. The ORAC values indicated that the tested NADES displayed antioxidative activity

Corrosion Protection Effect of Chitosan on the Performance Characteristics of A6063 Alloy

This article outlines the behaviour of water-soluble chitosan as an effective inhibitor on aluminium alloy in 3.65% NaCl at room temperature. The inhibitive ability of water-soluble chitosan was examined using electrochemical potentiodynamic polarization techniques, mass loss measurements and computational studies. The outcome of the experiment reveals that chitosan inhibited aluminium alloy in sodium chloride solution exhibits better corrosion protection than the uninhibited because chitosan nanoparticles minimize the ingression of chloride ion into the active sites of aluminium alloy by forming thin film on its surface. The losses in mass by the inhibited aluminium alloy were found to reduce as the concentration of chitosan increases. Results obtained showed that chitosan could offer inhibition efficiency above 70%. Polarization curve demonstrated that chitosan in 3.65% NaCl at room temperature acted as a mixed-type inhibitor. Adsorption of chitosan nanoparticles on the aluminium alloy was found to follow Langmuir adsorption isotherm with correlation regression coefficient (R2 ) value of 0.9961

Ionske kapljevine – razvoj i izazovi industrijske primjene

Establishment of novel, highly productive, and sustainable processes for the production of industrially important compounds is becoming a growing area of research. Due to non-volatility, inflammability, great thermal, chemical and electrochemical stability and also recyclability, ionic liquids are extensively studied as possible green replacement for widely used conventional molecular solvents. Due to the extremely large number of possible chemical structures of ionic liquids, the ability to design ionic liquids for specific applications makes them unique solvents in electrochemistry, analytical chemistry, organic synthesis and (bio)catalysis, separation processes, as well as functional fluids (lubricants, heat transfer fluids, corrosion inhibitors etc.). This paper presents a review of the scientific and technical literature related to ionic liquids, their basic properties, preparation and application, as well as the challenges of their application on an industrial scale.Uspostavljanje novih visokoučinkovitih i održivih procesa proizvodnje industrijski važnih kemikalija predmet je brojnih znanstvenih istraživanja. Stoga se ionske kapljevine, zbog neznatne hlapljivosti, nezapaljivosti, velike toplinske, kemijske i elektrokemijske stabilnosti, te posebice mogućnosti regeneracije, posljednjih godina intenzivno proučavaju kao zelena zamjena za sveprisutna tradicionalna škodljiva otapala. Budući da je broj mogućih kemijskih struktura ionskih kapljevina iznimno velik, mogućnost dizajniranja ionskih kapljevina za specifične namjene čini ih jedinstvenim otapalima za raznovrsnu uporabu u elekrokemiji, organskoj sintezi i (bio)katalizi, analitici, separacijskim postupcima, ali i kao funkcionalnih kapljevina (sredstva za podmazivanje, akumulatori topline, inhibitori korozije i dr.). U ovom je radu dat pregled znanstvene i stručne literature vezane uz ionske kapljevine, njihova karakteristična svojstva, pripravu i primjenu, ali i izazove njihove primjene u industrijskom mjerilu