Hexane

About: Hexane is a research topic. Over the lifetime, 3759 publications have been published within this topic receiving 57996 citations. The topic is also known as: CH3-[CH2]4-CH3 & hexyl hydride.

Comparison of Characteristics of Oils Extracted from a Mixture of Citrus Seeds and Peels Using Hexane and Supercritical Carbon Dioxide

Abstract: The processing of citrus fruits into juice is one of the world’s largest processing industries. The by-products of this industry are about 50 % of the raw processed fruit. This not only wastes a resource of potential value, but also causes disposal problems. The aim of this work was to study the characteristics of oils extracted from a mixture (MX) of citrus seeds (CS) and citrus peels (CP) using hexane and supercritical carbon dioxide (SC-CO2) so that those by-products can be valorized effectively. The SC-CO2 extraction conditions were 45 and 60 °C, 200 and 250 bar while for hexane was 70 °C. Hexane showed significantly (P < 0.05) higher yield than SC-CO2. The chemical composition was analyzed by GC–MS and phytosterols, monoterpenes, sesquiterpenes and oxygenated monoterpenes were the main compounds of the oils. The fatty acid composition was determined by GC and linoleic acid was the major fatty acid. The oxidative stability (OS) was performed by Rancimat and the hexane extracted oils showed higher OS. The antioxidant activity was tested with DPPH and ABTS assay and SC-CO2 extracted oils showed higher activity with IC50 values of 3.86 and 4.00 mg/ml respectively for MX and CP oils. Antimicrobial activity was tested for both extracted oils against gram positive and gram negative bacteria with SC-CO2 extracted oils exhibiting better inhibition. From this study, we can say that the citrus by-products can be valorized by combining CS and CP which could give the oils with potentiality to be used in many applications.

Physical Properties and Liquid−Liquid Equilibrium of the Ternary Mixture (Dimethyl Carbonate + Methanol + Hexane) at 298.15 K

Abstract: The density, refractive index, and speed of sound of the mixtures dimethyl carbonate + hexane and dimethyl carbonate + methanol + hexane have been measured at 298.15 K and atmospheric pressure, over the miscibility composition range. These results are used to calculate excess molar volumes, deviations of refractive index, and deviations in isentropic compressibility. The calculated quantities are further fitted to the Redlich−Kister and Cibulka equations to estimate the binary and ternary fitting parameters and root-mean-square deviations from the regression lines. Values of derived and excess properties were estimated and compared by different methods. Excess partial molar volumes at infinite dilution are also calculated. The liquid−liquid equilibrium of the ternary mixture dimethyl carbonate + methanol + hexane at 298.15 K has been measured. The UNIQUAC equation was used to correlate the experimental data, and the root-mean-square deviations are shown.

Novel applications of chloroperoxidase: enantioselective oxidation of racemic epoxyalcohols

Abstract: The CPO-catalysed enantioselective oxidations of racemic glycidol and cis -2,3-epoxyhexanol to the corresponding aldehydes were studied using tert -butyl hydroperoxide in the 9:9:1 and 18:1 mixtures of hexane:ethyl acetate:buffer and hexane:buffer, respectively. Temperature and pH (100 mM citrate buffer, pH 4.0–7.0) effects on enantioselectivity in the terms of ee for the less reactive alcohol enantiomers with conversion were studied.

Adsorptive process design for the separation of hexane isomers using zeolites

Abstract: The product of catalytic isomerization is a mixture of linear and branched hydrocarbons that are in thermodynamic equilibrium, and their separation becomes necessary in the petrochemical industry. Zeolite 5A is usually industrially used to sieve alkane isomers, but its pore size allows only the separation of linear alkanes from the monobranched and dibranched alkanes by a kinetic mechanism. A more efficient approach to improve the average research octane number would be to adsorptively separate the di-methyl alkanes as products and recycle both the linear and mono-methyl alkanes to the isomerization reactor. Since the microscopic processes of adsorbates in zeolites are generally difficult or impossible to determine by experiments, especially in the case of mixtures, molecular simulation represents an attractive alternative. In this computational study, we propose a conceptual separation process for hexane isomers consisting of several adsorptive steps. Different zeolite topologies were examined for their ability to conduct this separation based on adsorption equilibrium and kinetics.