Mixed Aqueous Surfactants Solution for Rapid Oil Extraction from Palm Kernel Seed

Adverse effects associated with the use of hexane or other similar organic extraction solvents for extracting oil from oilseeds have been a drive for alternative less toxic oil extracting solvents. This research focuses on oil extraction from grinded palm kernel using solution of mixed aqueous polyoxythylene (23) lauryl ether (BRIJ-35) and sodium dodecyl sulphate (SDS) surfactants and sodium chloride (NaCl) as the electrolyte. Grinded Biomass was agitated in the solution of the mixed surfactant, allowing the extracted oil to be liberated from the seeds as separate phase from the aqueous phase. The effect of SDS concentration, NaCl concentration, contact time and liquid/seed ratio on oil yield was studied. The extracted oil was subjected to Fourier Transform Infrared Spectroscope (FT-IR) characterization to determine the functional groups present in the oil. At optimum conditions for the mixed aqueous surfactant extraction (0.2379 wt.% SDS, 0.5995 wt.% BRIJ-35, 0.3wt.% NaCl, 10 ml/g liquid/solid ratio, 25 min contact time at 25oC), an optimum 78% oil yield was obtained. In contrast, at 50oC for 24hr, an optimum of 81% and 82% oil yield were obtained respectively when hexane and petroleum ether were used as oil extracting solvents. Addition of BRIJ-35 and NaCl to the SDS solution improved the oil yield. Oil extracted using mixed aqueous surfactants, petroleum ether and hexane have the same functional groups indicating the surfactant does not affect the quality of the oil extracted.

Computational Investigations of a pH-Induced Structural Transition in a CTAB Solution with Toluic Acid

In this work, molecular dynamics simulations were performed to study the pH-induced structural transitions for a CTAB/p-toluic acid solution. Spherical and cylindrical micelles were obtained for aqueous surfactants at pH 2 and 7, respectively, which agrees well with the experimental observations. The structural properties of two different micelles were analyzed through the density distributions of components and the molecular orientations of CTA+ and toluic acid inside the micelles. It was found that the bonding interactions between CTA+ and toluic in spherical and cylindrical micelles are very different. Almost all the ionized toluic acid (PTA−) in the solution at pH 7 was solubilized into the micelles, and it was located in the CTA+ headgroups region. Additionally, the bonding between surfactant CTA+ and PTA− was very tight due to the electrostatic interactions. The PTA− that penetrated into the micelles effectively screened the electrostatic repulsion among the cationic headgroups, which is considered to be crucial for maintaining the cylindrical micellar shape. As the pH decreased, the carboxyl groups were protonated. The hydration ability of neutral carboxyl groups weakened, resulting in deeper penetration into the micelles. Meanwhile, their bonding interactions with surfactant headgroups also weakened. Accompanied by the strengthen of electrostatic repulsion among the positive headgroups, the cylindrical micelle was broken into spherical micelles. Our work provided an atomic-level insights into the mechanism of pH-induced structural transitions of a CTAB/p-toluic solution, which is expected to be useful for further understanding the aggregate behavior of mixed cationic surfactants and aromatic acids.

Wetting and Spreading of Commercially Available Aqueous Surfactants on Porous Materials

The wetting properties of aqueous solutions of a commercially available surfactant at various concentrations on porous media are investigated using the KRUSS DSA100 shape analyzer and the ADVANCED software to process the data. Time evolution of both the contact angle and drop base diameter at each surfactant concentration after deposition were monitored. Three different porous substrates (sponges) were examined. The sponges used were a car sponge, dish sponge and audio sponge. The sponges were investigated both dry and at different degrees of saturation, that is, the amount of water absorbed into the sponge. It was found that pure distilled water droplets deposited on the dry porous media showed non-wetting. However, if droplets of surfactant solutions were deposited, then a change to a complete wetting case was found at all surfactant concentrations used. It has been observed that for all sponges, no matter the degree of saturation, they display a minimum contact angle after which the droplet is rapidly absorbed into the porous media.

Intestinal Lymphatic Delivery of Praziquantel by Solid Lipid Nanoparticles: Formulation Design,In VitroandIn VivoStudies

The aim of the present work was to design and develop Praziquantal (PZQ) loaded solid lipid nanoparticles (PZQ-SLN) to improve the oral bioavailability by targeting intestinal lymphatic system. PZQ is practically insoluble in water and exhibits extensive hepatic first-pass metabolism. PZQ SLN were composed of triglycerides, lecithin and various aqueous surfactants; were optimized using hot homogenization followed by ultrasonication method. The optimized SLN had particle size of123±3.41 nm, EE of86.6±5.72%. The drug release of PZQ-SLN showed initial burst release followed by the sustained release. Inspite of zeta potential being around −10 mV, the optimized SLN were stable at storage conditions (5±3°C and25±2°C/60±5% RH) for six months. TEM study confirmed the almost spherical shape similar to the control formulations. Solid state characterization using differential scanning calorimeter (DSC) and powder X-ray diffraction (PXRD) analysis confirmed the homogeneous distribution of PZQ within the lipid matrix. The 5.81-fold increase inAUC0→∞, after intraduodenal administration of PZQ-SLN in rats treated with saline in comparison to rats treated with cycloheximide (a blocker of intestinal lymphatic pathway), confirmed its intestinal lymphatic delivery. The experimental results indicate that SLN may offer a promising strategy for improving the therapeutic efficacy and reducing the dose.

Lubrication Properties of Aqueous Solutions with Polyethoxylated Ether (PEOE) Added

Aqueous solutions have found broad usages as lubricants, in conjunction with other possible utilizations, such as in metal working and other industries. Due to the inferior lubricity, functional additives are needed to improve their tribological performances among which aqueous surfactants are exclusively included. The film forming property of aqueous solution with polyethoxylated ether added (PEOE) is measured, taking consideration of the influences of the temperature and the concentration. The addition of PEOEs into aqueous solutions will largely increase the film forming capacity. But the concentration has only a minor influence on the lubrication property of the aqueous solutions with PEOEs. The cloud point will strongly alter the film forming characteristics.

Dynamic Viscosity Variation of Aqueous Solutions with Polyethoxylated Ether (PEOE) Added

Aqueous solutions have found broad usages as lubricants, in conjunction with other possible utilizations, in metal working and other industries. Due to the inferior lubricity, functional additives are needed to improve their tribological performances, including oil-in-water (O/W) emulsions or aqueous surfactants. The rheology of aqueous solution with polyethoxylated ether added (PEOE) is measured, including the influences of the temperature and the concentration on dynamic viscosity variation. The dynamic viscosity of PEOE aqueous solutions increases with PEOE concentration. The dynamic viscosity of PEOE aqueous solutions decreases with the rise of temperature up to cloud points. If the temperature is higher than cloud points, however, the dynamic viscosity will increase, through which a non Newtonian characteristic, i.e., the shear thinning, is expressed.