Sodium Soaps Research Articles

Study on small molecular organic compounds pyrolysed from rubber seed oil and its sodium soap.

Rubber seed oil (RSO) and its sodium soap were pyrolysed in a batch reactor to obtain low molar mass organic substances. The pyrolitic oil of RSO was redistilled and the distillates were characterized by GC–MS and FTIR. Density, acid value, saponification value and ester values were also measured according to the ASTM standard methods. A similar analysis was done for samples taken out at different time intervals from the reaction mixture. Industrially important low molar mass alkanes, alkenes, aromatics, cyclic compounds and carboxylic acids were identified in the pyrolysis process of rubber seed oil. However, pyrolysis of the sodium soap of rubber seed oil gave a mixture of hydrocarbons in the range of C14–C17 and hence it has more applications as a fuel.

Perfectly Wetting Mixtures of Surfactants from Renewable Resources: The Interaction and Synergistic Effects on Adsorption and Micellization.

This paper presents a study of the surface properties of mixtures of surfactants originating from renewable sources, i.e., alkylpolyglucoside (APG), ethoxylated fatty alcohol (AE), and sodium soap (Na soap). The main objective was to optimize the surfactant ratio which produces the highest wetting properties during the analysis of the solution of the individual surfactants, two- and three-component mixtures, and at different pH values. The results showed the existence of a synergistic effect in lowering the interfacial tension, critical micelle concentration and the formation of mixed micelles in selected solutions. We found that best wetting properties were measured for the binary AE:APG mixtures. It has been demonstrated that slightly lower contact angles values were observed on Teflon and glass surfaces for the AE:APG:soap mixtures but the results were obtained for higher concentration of the components. In addition, all studied solutions have very good surface properties in acidic, basic and neural media. However, the AE:soap (molar ratio of 1:2), AE:APG (2:1) and AE:APG:soap (1:1:1) compositions improved their wetting power at pH 7 on the aluminium and glass surfaces, as compared to solutions at other pH values tested (selected Θ values close to zero—perfectly wetting liquids). All described effects detected would allow less surfactant to be used to achieve the maximum capacity of washing, wetting or solubilizing while minimizing costs and demonstrating environmental care.

Self-Assembly of Bilayer Vesicles Made of Saturated Long Chain Fatty Acids.

Saturated long chain fatty acids (sLCFA, e.g., C14:0, C16:0, and C18:0) are potentially the greenest and cheapest surfactants naturally available. However, because aqueous sodium soaps of sLCFA are known to crystallize, the self-assembly of stable bilayer vesicles has not been reported yet. Here, by using such soaps in combination with guanidine hydrochloride (GuHCl), which has been shown recently to prevent crystallization, we were capable of producing stable bilayer vesicles made of sLCFA. The phase diagrams were established for a variety of systems showing that vesicles can form in a broad range of composition and pH. Both solid state NMR and small-angle neutron scattering allowed demonstrating that in such vesicles sLCFA are arranged in a bilayer structure which exhibits similar dynamic and structural properties as those of phospholipid membranes. We expect these vesicles to be of interest as model systems of protocells and minimal cells but also for various applications since fatty acids are potentially substitutes to phospholipids, synthetic surfactants, and polymers.

Lubrication properties of modified lard and rapeseed oil greases with sodium and lithium thickeners

Purpose – The purpose of this paper is to conduct research on the possibility of improving the tribological and utilization properties of lard and rapeseed oil bio-based greases by mixing it with ethanol and selection of thickener and modification with special biological additives. Design/methodology/approach – Rapeseed oil- and lard-based greases with sodium and lithium soap thickeners were mixed with either water or ethanol and modified with a special biological anti-wear additive. Tribological properties of modified lubricants evaluated on a four-ball machine. Findings – Rapeseed oil- and lard-based greases suspended in ethanol and modified with bio-additive have the same wear resistance as the industrial non-biological lubrication grease and much higher wear resistance as bio-based reference grease. The tribological efficiency of the additives is higher in greases of rapeseed oil and less efficient in lard-based greases. Oxidation and wear tests show that investigated bio-based greases have comparatively stable tribological properties also after their aging. Modified greases have sufficient consistence according penetration measurements and high thermal resistance according drop-point temperature measurements. All produced experimental greases pass within the category of the easily degradable materials. Originality/value – The greases mixed with the ethanol make possible to form more homogeneous and stable grease mixture. Modified bio-based greases have significantly higher wear resistance as bio-based reference grease, their lubrication properties are stable also after the aging and are categorized as easily degradable materials.

Removal of direct Yellow 27 dye using animal fat and vegetable oil-based surfactant

The textile industry uses large amounts of water in its processes. Such water ends up contaminated by a number of substances, including dyes, creating an environmental challenge. The present study aims at removing dye by applying the precipitation process using a sodium soap (anionic surfactant), derived from animal fat and vegetable oil, promoting dye decontamination using biodegradable materials. Sodium soap, in the presence of calcium ions, forms another insoluble surfactant. This new surfactant, under stirring, aggregates and forms hydrophobic flocs that are capable of adsorbing organic materials dissolved in aqueous solutions, including dyes. Dye removal was assessed considering the influence of initial surfactant concentration, temperature, pH, presence of electrolyte, equilibrium time, and stirring rate. Dye removal efficiency reached 97.6%.

Selective flotation of scheelite from calcite and fluorite using a collector mixture

Collector 733, a sodium soap (C12–16COONa) is widely used industrially for scheelite flotation. Low selectivity of 733 collector is always observed. In this study, a collector mixture of 733 and MES (sodium fatty acid methyl ester sulfonate) demonstrated a high selectivity for the flotation of scheelite from calcite and fluorite. An optimal mass ratio 4:1 of 733:MES was found, producing a 65.76% WO3 concentrate grade with a recovery of 66.04% from a feed material containing only 0.57% WO3. In addition, the effect of water hardness and water glass addition were studied. The results indicated that the presence of Ca2+ or Mg2+ had little effect on the adsorption of the collector mixture at the scheelite surface. Addition of water glass for depressing calcite and fluorite had no significant effect on the adsorption of the collector mixture on the scheelite surface. The advantages of this new collector mixture (733+MES) include lower cost, low dosage, high tolerance against water hardness and high selectivity, and this collector mixture has great potential for industrial application.

Water-free process for eco-friendly purification of biodiesel obtained using a heterogeneous Ca-based catalyst

The technologies conventionally used for biodiesel purification imply high consumptions of both energy and water. In the present work, biodiesel was produced by transesterification using a very active calcium glyceroxide catalyst and purified using water-free processes. The study focused on soaps removal that was the main product impurity. The best results were obtained when the crude biodiesel (methyl ester content of 90.2–91.2wt.% and calcium content of 372–393ppm) was pretreated with Na2CO3 and afterward treated by an ion-exchange resin (6wt.%) or a ceramic membrane (0.1μm). The purification was effective using biodiesel produced from both soybean oil and waste frying oil and the quality of the product agreed with the one obtained using the conventional water washing process. The effectiveness of the treatment could be explained by calcium elimination through precipitation as CaCO3 during pretreatment and sodium soaps removal by absorption into the resin or filtration by the ceramic membrane, according to the micelle formation mechanism. The studied process presents a high potential to remove calcium soaps from biodiesel.

Preparation and Optimization of Biodiesel Production from Mixed Feedstock Oil

In this paper, production of biodiesel from mixed feedstock oil (MFO) by three-step method and optimization of the process were studied by using regressive analysis. The random mixer of different oil was used for biodiesel preparation. The MFO contains 12 wt% free fatty acid (FFA) and its viscosity was 67.5 mm2/s. Because of higher FFA content transesterification method can’t be applied, so three-step method was conducted for biodiesel preparation. In the three-step method, the first step was saponification of the oil followed by acidification to produce FFA and finally esterification of FFA to produce biodiesel. In the saponification reaction, various reaction parameters such as oil to sodium hydroxide molar ratio and reaction time were optimized. Produced sodium soap was acidified with excess molar ratio of HCl to produced FFA. In the esterification reaction, produced FFA was reacted with methanol in presence of acid catalyst and the FFA content was reduced to 0.98wt%. A factorial design was studied based on viscosity for esterification reaction and developed to obtain the higher yield of biodiesel. Finally various properties of biodiesel such as FFA content, viscosity, specific gravity, cetane index, pour point etc. were measured and compared with biodiesel and petro-diesel standard.

Rolling Bearing Performance and Film Formation Behavior of Four Multiply Alkylated Cyclopentane (MAC) Base Greases for Space Applications

Four multiply alkylated cyclopentane (MAC)-based greases, used for space applications, were used for rolling contact fatigue tests employing thrust ball bearings. These greases were R2000, ML, MU, and 5200 and were made from the same base oil 2001A. Each grease had a different thickener, which were sodium soap, Li soap, urea, and polytetrafluoroethylene (PTFE), respectively. The effect of the grease thickener on the ball bearings' fatigue life in vacuum and atmospheric environments was investigated via testing. For the greases R2000, MU, and ML it was found that the oil film formation in the experiments performed under vacuum conditions declined remarkably in comparison to under atmospheric conditions. For the 5200 grease, the oil film formation was almost the same as under atmospheric conditions. These results were supported by the occurrence of cage wear in the ball bearing fatigue tests. In the absence of sufficient films, high wear rates were measured.

Emulsifiers from renewable materials: an eco-friendly synthesis and properties

The focus of this study was the preparation of novel bio based polyglycerol emulsifiers characterized by a one pot synthesis, thus by modified properties with respect to interfacial activity and effectiveness as emulsion stabilizers. The final products of the esterification process, carried out in the presence of carboxylates were used directly as emulsifiers (without purification or fractionation). Polyglycerol emulsifiers obtained in proposed conditions can be tailored to stabilize the defined emulsion system. The modification of the surface activity of emulsifiers may be obtained by programming the fatty acid acyl group in the polyglycerol ester as well as the hydrocarbon chain length in sodium soap and concentration of this compound in the reaction mixture.

Pengembangan Membran Magnesol untuk Pemurnian Biodiesel

Magnesol membrane has been prepared by mixing chitosan polymer with magnesol particles via phase inversion method. The optimum compositions of adsorptive membranes were 3% chitosan, 15% DMF and 60% loading adsorbent. The porosity of these membranes was 34,17% and swelling degree was 51,91%. The membrane clean water flux was 224,4 Lm‑2h‑1 at a transmembrane pressure of 2.5 bar. The adsorptive membrane possesses an open and interconnected porous structure with a large surface area available for biodiesel purities adsorption. The results showed that after contacting in 60 minutes, numbers of acid value was reduced as 81,12% which is in accordance with value of SNI quality standards. In addition, the soap content adsorbed was 86,74% as potassium soap and 86,73% as sodium soap. The regenerated membrane can be reused with mantaining the high adsorption capacity. The methanol was better than ethanol to regenerate the magnesol membrane. The Magnesol membrane will be a new alternative method for biodiesel purification.Keywords: biodiesel, membrane adsorption, chitosan, magnesol, acid number, soap

Biodegradability and cytotoxicity of choline soaps on human cell lines: effects of chain length and the cation

Using choline as a counterion in fatty acid surfactants substantially increases their water solubility as compared to classical sodium and potassium soaps, and thereby enables the application of desirable longer-chain derivatives at ambient temperature. Since choline can be decomposed both physiologically and environmentally, corresponding fatty acid soaps are considered to be highly biocompatible. Recent toxicity and biodegradability studies of choline ionic liquids, including anions such as short- and middle-chain alkanoates, have verified the expected low toxic impact. However, according to the European Cosmetic Directive 76/768/EEC, all salts of choline are forbidden in cosmetic products, mainly just due to its classification as a quaternary ammonium ion. In order to facilitate their application in the future, we have investigated the biodegradability of choline soaps (ChCm) with alkyl chain lengths of m = 12–18 according to the OCDE 301F standard. Further, the cytotoxicity of ChCm surfactants with m = 8–16 was determined, both for odd- and even-numbered fatty acids. Studies were carried out using two different human cell lines, namely cervix carcinoma cells (HeLa) and keratinocytes (SK-Mel-28). For a better comparability to common soaps and to shed light on the influence of the cation, sodium and potassium homologues were also investigated. Results reveal an unexpected non-linear relationship between the hydrophobic chain length and the IC50 value. Most importantly, the presented data show that IC50 values of ChCm surfactants coincide with those of the widely applied sodium and potassium soaps. This demonstrates that choline carboxylate surfactants are harmless and thus strongly supports their applicability in customer end products.

The correlation of microstructure morphology with gelation mechanism for sodium soaps in organic solvents

Using sodium caprylate as a model molecule, in the present work, we unraveled the gelation mechanism of sodium soaps in organic solvents from its correlation with the microstructure morphology. It is interesting to find that both the formation of organogels and radiation-like gel fibers are controlled by Na+ concentration in the system. As the gel-activator, the sodium ions not only accelerate the gelation process and enhance the gel networks, but also induce the morphology transformation from fibers to radiative nanoribbons. TEM and XRD characterization reveals that the Na+ enhanced effect should be ascribed to the structure transformation of sodium caprylate from layers to hexagonal packing, due to its reduced inter-separation after the addition of Na+. Based on these results, the gelation mechanism of sodium soaps has been also proposed.

Reducing Oil Losses in Alkali Refining

AbstractNeutralization is an important step in the chemical refining of edible oils. Free fatty acids (FFA) are generally removed in neutralization as sodium soaps but neutral oil is also entrapped in the emulsion and removed with the soap during centrifugation. Thus, alkali neutralization causes a major loss of neutral oil in the chemical refining of edible oils. The effects of demulsifiers (NaCl, KCl, Na2SO4 and tannic acid) on reducing alkali refining losses of refined palm, soybean, and sunflower oils (used as model oils) incorporated with FFA from rice bran oil were investigated. Adding small amounts of demulsifiers to the alkali neutralization step significantly reduced neutral oil loss of these model oils. All demulsifiers except for tannic acid had similar effects on refining losses in all oil model systems. The optimum demulsifier content was 1.0 % (w/w of oil).

Tratamentos dos efluentes gerados na produção de biodiesel

The wastewaters from biodiesel production contain as primarily wastes sodium or potassium soaps, fatty acids, glycerin, alcohol and other contaminants. In general, these waters are chemically unsuitable for release to any water body, so, it is necessary the adoption of techniques for the treatment of this effluent. In this review, electrochemical, biological, physicochemical, and combined treatments reported for the removal of the wastewater containing pollutants come from biodiesel production have been summarized. In addition, the recovery, the reuse, the energy production and the synthesis of new compounds from the organic matter contained in this kind of effluent are also reviewed.

Les lubrifiants secs pour le tréfilage

The wire drawing process consists in reducing the diameter of a metallic wire by traction through a die. Wire drawing dry lubricant is a complex product not only considering the selection of raw materials, theirs formulation but also the manufacturing process. It can be assimilated to an elaborate mixture of mainly sodium and calcium soaps with mineral elements (fillers) and additives. The composition and the association of these elements allow the control of thickness and consistence of the lubricant film through the dies. Fatty matters mainly used for the manufacturing of these soaps are tallow and stearic acid extracted from tallow. Initially considered as a waste and questioned during the BSE crisis, tallow is nowadays on demand especially on the biofuels market.

Micellization in aqueous solutions of mixed surfactants containing alkylpolyglucosides

Tensometry is used to find the dependences of critical micelle concentration in aqueous solutions on the composition of mixed systems comprising anionic surfactants (alkyl sulfates and individual sodium soaps) and alkylpolyglucosides. Mixed micellization is revealed and the compositions of micelles and the parameters of intermolecular interaction are calculated. The average hydrodynamic diameter of micelles is measured by dynamic light scattering.

Production of High Heat Value Fuels by Microwave Pyrolysis of Microalgae Oil Soap under Nitrogen Environments

The purpose of this study is to preparing high heat value fuels. In present investigation, sodium soap made from microalgae oil was used as the experimental material with significant molecular polarity, then by using microwave heating technology, which may preferentially activate the polar molecule and functional groups of the soap molecular, leading to the high selectivity of decarboxylation. The hydrocarbon content arrived maximum in 900W, when was investigated in different microwave radiation power, obtained pyrolysis liquid similar with high heat value fuel. The hydrocarbon content were usually above 70%. In addition, its density and dynamic viscosity are 0.845-0.870g/cm3 and 2.15-2.70mm2/s.

Fibrillar films obtained from sodium soap fibers and polyelectrolyte multilayers

An objective of tissue engineering is to create synthetic polymer scaffolds with a fibrillar microstructure similar to the extracellular matrix. Here, we present a novel method for creating polymer fibers using the layer-by-layer method and sacrificial templates composed of sodium soap fibers. Soap fibers were prepared from neutralized fatty acids using a sodium chloride crystal dissolution method. Polyelectrolyte multilayers (PEMs) of polystyrene sulfonate and polyallylamine hydrochloride were deposited onto the soap fibers, crosslinked with glutaraldehyde, and then the soap fibers were leached with warm water and ethanol. The morphology of the resulting PEM structures was a dense network of fibers surrounded by a nonfibrillar matrix. Microscopy revealed that the PEM fibers were solid structures, presumably composed of polyelectrolytes complexed with residual fatty acids. These fibrillar PEM films were found to support the attachment of human dermal fibroblasts.

Thermal behaviour of metal soaps from biodegradable rubber seed oil

Soaps are a class of surface active compounds derived from natural oils and fats. Double decomposition reactions permit the synthesis of metallic soaps, which are long-chain carboxylates of metal ions, from alkaline ones such as sodium, potassium or ammonium soaps. Metallic soaps are commercially important as they find use in diverse applications such as driers in paints or inks, components of lubricating greases, heat stabilizers for plastics (especially PVC), catalysts and water proofing agents, fuel additives and cosmetic products amongst others. Many of these applications are related to the thermal properties of these compounds and the thermal behaviour of metal soaps in terms of decomposition processes is of great importance. Rubber seed oil (RSO) which is an unsaturated triglyceride abundantly available in Nigeria, India and Australia is an excellent starting material for metal soaps. In this study rubber seed oil having 2.2% myristic acid, 7.6% palmitic acid, 10.7% stearic acid, 20.61% oleic acid, 36.62% linoleic acid, 22.5% linolenic acid was used in making barium, calcium, cadmium and zinc soaps. The thermal behaviour of soaps (Ba, Ca, Cd and Zn) of rubber seed oil for use as additives in the processing of poly(vinyl chloride) (PVC) was investigated by thermal gravimetry and differential scanning calorimetry. The stability of the soaps was examined by thermogravimetry up to 873 K at a constant heating rate of 10 °C min−1. The soaps were found to be thermally stable up to 473 K as they recorded less than 5% mass loss at this temperature with values of apparent activation energy for decomposition varying from 52 to 96 kJ mol−1. Differential scanning calorimetric studies of the soaps revealed melting and decomposition behaviour of metal soaps.