Density F and viscosity η were measured for binary mixtures of cotton seed + babassu and soybean + babassu biodiesel over the composition range at several temperatures of (293.15, 313.15, 333.15, 353.15, and 373.15) K and atmospheric pressure. The viscosity deviation (∆η) was determined and fitted by a Redlich-Kister type function in terms of mass fraction (w). The Joback's method combined with Lee-Kesler and Rackett equations were used to calculate the densities of the binary mixtures of cotton seed + babassu and soybean + babassu biodiesel. The experimental and estimated density values gave almost identical values with a relative differences of less than 0.21 %. The Ceriani's group contribution method was used to predict the viscosity, with a maximum relative deviation of 31 %.

Viscosity η and density ρ of binary mixtures of coconut + colza and coconut + soybean biodiesel have been measured over the whole composition range at T = (293.15, 313.15, 333.15, 353.15, and 373.15) K and at atmospheric pressure. Densities and viscosities data were correlated with R-square adjustment and the Andrade equation, respectively, with good agreement. The deviations of viscosities (Δη) have been calculated from the experimental data. To predict the density and viscosity we have used Joback’s method and a group contribution model proposed by Ceriani et al. (J. Chem. Eng. Data 2008, 53, 877−880), respectively.

Biodiesel has many advantages because it is a biodegradable, nontoxic fuel and its production results in less particulate matter. For this reason it has been studied in many fields of science as a substitute for mineral fuels. Short chain alcohols such as ethanol have been used for extraction of soybean and sunflower biodiesel in the literature. The present paper reports liquid–liquid equilibrium data for systems containing soybean biodiesel + glycerol + ethanol at (293.15 and 323.15) K and sunflower biodiesel + glycerol + ethanol at (298.15 and 313.15) K. Binodal curves were obtained by the cloud-point method, while tie-line compositions were obtained by density measurements. The values of distribution coefficients and selectivities indicate that the ethanol is a good solvent for the extraction of soybean biodiesel and sunflower biodiesel from glycerol. The reliability of experimentally measured tie-line data can be ascertained by applying the Othmer–Tobias equation. The experimental data were correlated by the nonrandom two-liquid (NRTL) model, using the simplex minimization method with a composition-based objective function. The results found in this work were considered satisfactory, by analyzing statistical parameters using root-mean-square deviations.

-In this study, the phase behaviour of emulsified systems (oil + biosurfactant + water) was analyzed. The biosurfactant was produced in a 4-L batch bioreactor by Bacillus subtilis LAMI005, using residual glycerine from biodiesel production as a carbon source. Fourier Transform Infrared Spectroscopy (FT-IR), Nuclear Magnetic Resonance (NMR), and High Performance Liquid Chromatography (HPLC) analyses demonstrated that the biosurfactant produced by Bacillus subtilis (LAMI005) consists of a lipopeptide similar to surfactin. The influences of temperature and the composition of oil + biosurfactant + water were determined by using phase diagrams. Three types of oil were used, namely: motor oil, hydrogenated naphthenic oil (NH140) and castor bean oil. The emulsified systems were analyzed using optical micrography. The results presented here indicated that the biosurfactant produced in this work presents a potential use as stabilizing agent for oil-in-water emulsions.

No abstract