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.

Screening Monoethanolamine As Solvent to Extract Phenols from Alkane

Abstract: Coal tar is a byproduct of low temperature coal carbonization. The separation of the compounds has great significance since its main component is the mixture of phenols and hydrocarbons. In this paper, the separation of specific phenolic compounds from model coal tar (phenols + hexane) was studied. The solvent was screened by empirical analysis, the universal quasichemical functional group activity coefficient (UNIFAC), and conductor-like screening model COSMO-SAC (segment activity coefficient). COSMO-SAC was used to calculate the capacity, selectivity, and performance index of solvents. Finally, the monoethanolamine (MEA) was selected as the solvent to extract the phenols. The liquid–liquid equilibrium for the ternary mixture of phenols + hexane + MEA was measured at 303.15 K and 323.15 K under atmospheric pressure, and the results showed that MEA provided a high distribution coefficient, efficiency, and selectivity for phenols. Meanwhile, the extraction process of phenols was simulated based on the nonr...

Engineering molecular recognition in alkane oxidation catalysed by cytochrome P450cam

Abstract: The activity, selectivity and coupling efficiency of alkane oxidation by the monooxygenase enzyme cytochrome P450cam can be enhanced by engineering the active site topology to accommodate different alkanes: reducing the active site volume by the Y96F–V247L double mutations resulted in four-fold higher activity for the oxidation of hexane (1) than 3-methylpentane (2) while the larger active site of the Y96A–V247A double mutant gave rise to a two-fold preference for 2 over 1.

Oil recovery and lecithin production using water degumming sludge of crude soybean oils

Abstract: BACKGROUND: Wet gums produced during aqueous degumming of crude soybean oils are currently processed to produce lecithin or added to meals to increase their nutritive value for animal feed. Oils occluded in these gums are generally not recovered or processed. In this work, three methods to recover occluded oil and obtain lecithin from wet gums were assayed: direct extraction of oil with cold acetone (Method I), extraction after water elimination under vacuum (Method II) and by solvent partition with hexane/ethanol (Method III). RESULTS: Higher oil yields (up to 588 g kg−1 of occluded oil) were obtained when water was eliminated before extraction (Methods II and III). No significant differences were observed in lecithin yields between three methods (720–807 g kg−1 of dried gums). Recovered oils had acidity = 16.7–21.7 g kg−1 as oleic acid, TOTOX (total oxidation) values ≤ 8.82, unsaponifiable matter = 9.0–12.1 g kg−1, and Phosphorus = 87–330 mg kg−1. Lecithins obtained by Methods I, II and III hexane phase had the same purity level (610–691 g of total measured phospholipids kg−1). CONCLUSIONS: The occluded oil in soybean wet gums can be recovered, with quality and stability indexes compatible with their reinsertion in the productive process, by water elimination and extraction with acetone. Lecithins can be obtained with different phospholipid composition and diverse application fields. Copyright © 2008 Society of Chemical Industry

Densities, viscosities, and refractive indices of the binary liquid systems n-alkanes + isomers of hexane at 298.15 K

Abstract: In this paper the viscosities, densities, and refractive indices of nine binary liquid systems containing n-alkane + isomers of hexane have been determined at 298.15 K. The viscosity values were fitted to the McAllister three-body model and the Redlich-Kister-type equation. The results with these models agree with experimental data with an average absolute deviation of less than 0.6%. The nine binary liquid systems studied were hexadecane with 2-methylpentane, 3-methylpentane, 2,2-dimethylbutane, and 2,3-dimethylbutane; dodecane with 2-methylpentane, 2,2-dimethylbutane, and 2,3-dimethylbutane; and tetradecane with 2-methylpentane and 2,3-dimethylbutane.

Allium Chemistry: Structure, Synthesis, Natural Occurrence in Onion (Allium cepa), and Reactions of 2,3-Dimethyl-5,6-dithiabicyclo[2.1.1]hexane S-Oxides

Abstract: Peracetic acid oxidation of di-1-propenyl disulfide (8) gives (±)-(1α,2α,3β,4α,5β)-2,3-dimethyl-5,6-dithiabicyclo[2.1.1]hexane 5-oxide (10a; 10%) and (1α,2α,3α,4α,5β)-2,3-dimethyl-5,6-dithiabicyclo[2.1.1]hexane 5-oxide (11a; 11%), both also isolated from extracts of homogenized onion. Compound 10a could be converted into bissulfoxides (±)-(1α,2α,3β,4α,5α,6α)-2,3-dimethyl-5,6-dithiabicyclo[2.1.1]hexane 5,6-dioxide (16) and (±)-(1α,2α,3β,4α,5β,6α)-2,3-dimethyl-5,6-dithiabicyclo[2.1.1]hexane 5,6-dioxide (17a); these could be oxidized further to (±)-(1α,2α,3β,4α,5α,5β,6α)-2,3-dimethyl-5,6-dithiabicyclo[2.1.1]hexane 5,5,6-trioxide (18a) and (±)-(1α,2α,3β,4α,5α,5β,6β)-2,3-dimethyl-5,6-dithiabicyclo[2.1.1]hexane 5,5,6-trioxide (18b) from 16 and 18a from 17a. Extended oxidation of 10a gave (±)-trans-2,3-dimethyl-5,6-dithiabicyclo[2.1.1]hexane 5,5,6,6-tetraoxide (19). Oxidation of 11a gave (1α,2α,3α,4α,5β,6β)-2,3-dimethyl-5,6-dithiabicyclo[2.1.1]hexane 5,6-dioxide (21a) which was further oxidized to trioxides (1α,...