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The major downfalls of vegetable oils, namely soybean oil in this research, are very detrimental to engine lubricant performance. A unique - out of the box- additive package is needed to compensate for the lubricant deficiencies. This research searched for unique additive solutions to the problems of oxidation and heat stability, low temperature pumpability, and fluid corrosiveness. The additive solutions were then tested in preliminary engine tests. In this research, several formulations were developed that passed the main engine oil low temperature test, the mini rotary viscometer. The lubricants met the passing viscosity requirements of 60,000 centipoise and exhibited no yield stress. The formulation was tested using ASTM D 6594[1], hot tube corrosion bench test, and Sequence VIII corrosion engine test. Acceptable results were seen in both tests. Oxidation bench tests were used to examine soybean engine oil stability. Several antioxidants showed improved performance in the TFOUT oxidation induction time bench test. A mixture of those antioxidants was tested in the Sequence IIIG engine test. All of the formulas failed the Sequence IIIG tests. However, improved test results were seen when the soybean oil was decreased from 15 wt % to 5 wt % in the formulations.

The ability of a lubricating oil to reduce friction in mechanical surfaces which are in relative sliding motion depends on the base oil behaviour. Previous studies have demonstrated that temperature has a significant influence on the friction behaviour of mineral and synthetic base oils by using a laboratory based friction testing machine. However, the effect of a constantly changing load under different temperature conditions has not been explored fully. In this study, the effect of an increasing load on the friction behaviour of four six different mineral base oils and a polyalphaolefin (PAO) base oil were studied using the SRV4® tribometer. The sliding surfaces were AISI 52100 steel ball and disc. The average loads (range: 50 – 250 N), temperatures (range: 40 – 120 oC), relative humidity of 20 % and a sliding speed of 0.2 m.s-1 were selected as the test conditions. The seven base oils were selected from four API base oil groups. Stribeck curves were used as a tool to characterize the friction behaviour of the base oils. The results show that for all the base oils, the coefficient of friction and the Stribeck parameter decrease gradually with the increase in applied normal load under constant temperature conditions. The increase in temperature increased the coefficient of friction and decreased the Stribeck parameter at each load stage. The external friction mechanisms dominated the friction behaviour under all test conditions. Viscosity showed a strong influence on the film forming characteristics of the seven base oils only at 40 and 60 oC. Between 80 and 120 oC, the oil-surface interactions were predominant. The results further demonstrated that effect of an increasing temperature on the coefficient of friction was bigger between 80 and 100 oC for all Group III base oils and was consistent between 40 and 120 oC for the Group III+ and PAO base oil. The highly saturated (PAO and Group III+) base oils have demonstrated good thermal stability and less reactivity compared to the less saturated base oils (GI and GIII) under all test conditions. The friction behaviour of the PAO base oil was the most affected by the presence of dissolved water. The presence of water proved to increase the friction at the sliding steel interfaces. / Dissertation (MEng)--University of Pretoria, 2018. / Chemical Engineering / MEng / Unrestricted

Nynas AB is a company that refines oil  for different applications such as insulating oils  for the electrical industry and base oils for both the lubricant and chemical industry. Different types of base oils are produced for the lubricant industry in order to provide required properties such as good viscosity, solvency, volatility, etc. But sometimes, the oils produced in the refineries (known as “straight cut” oils) do not have the all properties required by a customer, and a way for achieving those properties is to blend different straight cut base oils. To save money and time, empirical correlations are used to facilitate the prediction of the properties of those blends.Those correlations are adapted to products from a single site produced from certain crude oils. The company has recently decided to introduce a new stream of products with different characteristics, which means that the new properties of the products and blends can not be predicted by using the existing empirical correlations. The objective of this project was to analyze blends containing these new products and find the new correlations. The names of the oils are classified information and were renamed in the report and also number of the tables with result in appendices has been reduced to protect Nynas AB.  The correlations were surprisingly good for most of the blends. The differences between the values obtained by the blending program (which was calculating the properties) and the experimental values were very small. But the calculated values for properties such as flash point and pour point, were quite different from the experimental ones for some of the samples. Finally, there was one type of blends, between the Naphthenic oil 2 (N 2) and Paraffinic oil B (P (B)), were it was not possible to get any results with the blending program, because the viscosities at 40 °C of those oils (N 2 and P(B)) were too similar. As mentioned before, the property that was most difficult to predict was the pour point, specially for blends containing paraffinic oil blend with a naphtenic oil. However, suggestions were made based on the experimental values of how to get correlations based on. Anyhow, empirical correlations were developed based on the experimental data.

[pt] A constante procura por desenvolvimento sustentável tem originado a criação de novas técnicas de avaliação dos custos ambientais nos sistemas de produção. Atualmente a produção de óleos lubrificantes está sendo ambientalmente avaliada devido aos grandes impactos ambientais gerados pela produção, utilização e disposição final dos óleos de base mineral. Como alternativa para os óleos de bases minerais vem-se estudando a substituição por óleos oriundos de bases animais e vegetais, os quais apresentam melhores características ambientais. Este trabalho teve por objetivo realizar uma análise de ciclo de vida simplificada (berço-porta) das fases de produção de 1 kg de óleo de base mineral e 1 kg de óleo de base de óleo de jatropha com a utilização de uma análise de sensibilidade. A comparação para a obtenção dos dados foi realizada nos mesmos cenários de produção tanto para os óleos lubrificantes de base de jatropha quanto para os óleos lubrificantes de base mineral. Os resultados nestes cenários indicaram que na produção do óleo de jatropha, o potencial de aquecimento global foi 1,01 kg maior do que o cenário base da produção do óleo mineral; o potencial de eutrofização de água foi 2,06E-04 kg maior do que o cenário base da produção do óleo mineral; o potencial de toxicidade humana foi 0,08 kg maior do que o cenário base da produção do óleo mineral e o potencial de depleção de água foi 1,33E-01 kg maior do que o cenário base da produção do óleo mineral. No cenário base da produção do óleo mineral, o potencial de depleção de combustíveis fósseis foi 0,70 kg maior do que o cenário base da produção do óleo de jatropha. Entretanto, no contexto desta modelagem deve-se ainda levar em consideração outros parâmetros, como os relacionados às limitações geográficas, pois algumas discrepâncias nas análises do ciclo de vida dos óleos podem ocorrer. / [en] The continuously effort to reach the sustainable development has led to the creation of new techniques for assess environmental costs of the production systems. Nowadays the production of mineral oil base lubricants is assessed due to the large environmental impacts generated in their production, use and final disposal. As alternatives to the substitution of mineral oil base lubricants, vegetable oil base lubricants have been studied and used because their environmental characteristics. Hence, this study focused on execute a simplified LCA (cradle-to-gate analysis) for the production phase of 1 kg of mineral base oil and 1 kg of jatropha base oil trough a sensitivity analysis. The comparison for both oil bases was performed under the same production scenarios. Results shown that the jatropha base oil production scenario presented 1,01 kg more than the base mineral oil production scenario; the fresh water eutrophication potential had 2,06E-04 kg more than the base mineral oil scenario; the human toxicity potential presented 0,08 kg more than the base mineral oil scenario; the water depletion potential showed 1,33E-01 kg more than the base mineral oil scenario. On the mineral base oil production scenario, the fossil depletion potential shown 0,70 kg more than the base jatropha oil production scenario. However, it had to still take in consideration parameters such as geographic limitations, due to some discrepancies in the life cycle assessment of oils can occur.

other / no / The effect of sulphuric acid on the chemical and physical behaviour of the piston ring lubricant in a marine engine cylinder was investigated. To reveal the basic influence of H2SO4 on the lubricant film, the saturated hydrocarbon Squalane (C30H62) was chosen as a simple model oil. The interfacial tension between aqueous H2SO4 (0-98% w/w) and C30H62 was measured between -3 and 165 degrees C to understand droplet formation in the lubricant. Interfacial tension decreases with increasing acid concentration and is temperature dependent. / The wettability of engine parts with corrosive sulphuric acid was characterised by the contact angle. The contact angle of H2SO4 (0-98% w/w) on a grey cast iron cylinder liner material (Wartsila, RT84) and a piston ring chrome-ceramic coating (Federal Mogul Goetze, CKS, empty set960 mm) immersed in C30H62 was measured over a temperature range from 20 to 165 degrees C. In general, larger contact angles were measured under higher temperature conditions and on chrome surfaces. / In addition to the physical measurements, chemical reaction between H2SO4 and C30H62 was observed which influenced the interfacial tension, visual appearance, phase separation and formation of solid matter. The reaction time was found to be faster than the neutralisation times of commercially formulated lubricants. The reaction products were analysed using FTIR spectroscopy and EDX to find oxidation and sulphonation.

Lubricant is a common name for a large group of products that are essential for almost every engine or other machinery equipment that include mechanical part movements. Their main application is reduction of the friction between two rubbing surfaces by interposing a lubricating film between them. Other important functions of lubricants beside lubrication are; heat transfer, energy efficiency enhancement, corrosion and oxidation protection. All types of lubricants mainly consist of base oil and additives. Base oils are mainly hydrocarbon compounds, while additives are various chemical compounds added to the base oil to enhance some of the already existing properties, or to impose new properties that are beneficial for application purposes. During the storage period, where different storage conditions can occur, many of the requirements for lubricants chemical and physical stability needs to be fulfilled. Inappropriate storage conditions can cause physical and chemical changes in lubricants, which can make them unusable for the intended application. The effects of different storage conditions on lubricants stability were investigated in this work. The experimental part of this project was conducted at Fuchs Lubricants Sweden AB. At the beginning of the experiment, twelve 2L high density polyethylene bottles (HDPE) filled with the lubricant, were divided into three groups. The first group consisted of four closed HDPE bottles previously filled with the lubricant that were stored at 9 °C, 22 °C, 45 °C and 80 °C. The second and the third group consisted also of four open bottles and four bottles with added distilled water stored at the same storage temperatures. The amount of lubricant was approximately the same in all bottles. At different time intervals sample aliquots from the top, middle and the bottom layer were taken from these bottles and analyzed. The effects of different storage conditions on the lubricant’s stability and homogeneity were acquired by two distinctive spectroscopic methods. Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES) was used for elemental composition analysis, while the Fourier Transform Infrared (FTIR) Spectroscopy was used for evaluation of chemical changes on molecular level. Results from ICP-AES analyses showed almost homogeneous elemental distribution, virtually unaffected by different storage conditions in all sample bottles. Results from FTIR analyses showed that observed changes in absorption peaks (673, 863, 972. and 1267 cm-1) took place almost simultaneously at all three layers in all bottles stored at four different temperatures. These results suggest that the analyzed lubricant was stable and homogeneous for the observed period. The lowest storage temperature caused minimal changes in the lubricant and can be considered as optimal storage temperature for this product. It was also observed that increased temperature, direct exposure to oxygen and presence of water catalytically affected the rate of these changes. A part of this project was to validate the method used for ICP analysis. For this purpose, the following method performance parameters were investigated: linearity, precision, accuracy, Limit of detection (LOD) and Limit of quantification (LOQ). The obtained results showed that linearity of the method for all elements, in the used standard, was confirmed based on the set criteria. Precision and accuracy were tested in repeatability conditions and at four different concentration levels. The obtained results showed that accuracy of the method increased with concentration, and was highest for 50 ppm, for almost all elements. The highest precision (< 2 % RSD), for almost all elements was obtained for the concentration of 25 ppm. The LOD values were between 0.01 and 1.42 ppm while calculated LOQ values were between 0.04 and 4.73 ppm. / Smörjmedel är det gemensamma namnet för en stor produktgrupp som är nödvändig för nästan alla motorer eller annan maskinutrustning som inkluderar mekaniska delrörelser. Deras huvudsakliga tillämpning är att minska friktionen mellan två ytor i rörelse genom att införa en smörjfilm mellan dem. Andra viktiga funktioner förutom smörjning är; värmeöverföring, energieffektivisering, korrosion-och oxidationsskydd. Alla typer av smörjmedel består huvudsakligen av basolja och tillsatser. Basoljor är huvudsakligen kolväteföreningar medan tillsatser är olika kemiska föreningar som läggs till basoljan för att förbättra några av de befintliga egenskaperna eller att införa nya egenskaper som är fördelaktiga för applikationsändamål. Under lagringsperioden, där olika lagringsförhållanden kan uppstå, måste många av kraven på smörjmedlens kemiska och fysikaliska stabilitet uppfyllas. Olämpliga lagringsförhållanden kan orsaka fysiska och kemiska förändringar i smörjmedlen som kan göra dem oanvändbara för avsedd användning. Effekterna av olika lagringsförhållanden på smörjmedelstabilitet undersöktes i detta arbete. Experimentell del av detta projekt genomfördes hos Fuchs Lubricants Sweden AB. I början av experimentet, tolv 2L högdensitetspolyetenflaskor (HDPE) fyllda med smörjmedlet, uppdelades i tre grupper. Den första gruppen bestod av fyra slutna HDPE-flaskor som ifylldes med smörjmedlet och som lagrades vid 9 ° C, 22 ° C, 45 ° C och 80 ° C. Den andra och den tredje gruppen bestod också av fyra öppna flaskor och fyra flaskor med tillsatt destillerat vatten lagrat vid samma lagringstemperaturer. Mängden av smörjmedel var ungefär lika i alla flaskor. Vid olika tidpunkter togs prov från topp-mitten-och bottenskiktet från dessa flaskor och analyserades. Effekterna av olika lagringsförhållanden för smörjmedelsstabiliteten och homogeniteten förvärvades genom två distinkta spektroskopiska metoder. Induktivt kopplad plasma atomemissions-spektroskopi (ICP-AES) användes för elementsammansättningsanalys medan Fourier transform infraröd spektroskopi (FTIR) användes för utvärdering av kemiska förändringar på molekylär nivå. Resultat från ICP-AES-analyser visade nästan homogen fördelning av element, opåverkad av olika lagringsförhållanden i alla provflaskor. Resultat från FTIR-analyser visade att observerade förändringar i absorptionstoppar (673, 863, 972 och 1267 cm-1) inträffade nästan samtidigt i alla tre skikten i flaskorna lagrade vid fyra olika temperaturer. Dessa resultat tyder på att det analyserade smörjmedlet var stabilt och homogent under den observerade perioden. Den lägsta lagringstemperaturen orsakade minimala förändringar i smörjmedlet och kan betraktas som den optimala lagringstemperaturen för denna produkt. Resultatet visade också att ökad temperatur, direkt exponering för syre och närvaro av vatten hade katalytiskt påverkat graden av dessa förändringar. En del av detta projekt var att validera metoden som används för ICP-analys. För detta ändamål undersöktes följande metodprestanda-parametrar: linjäritet, precision, noggrannhet, detektionsgräns (LOD) och kvantifieringsgräns (LOQ). De erhållna resultaten visade att linjäriteten för metoden, för alla element, i den använda standarden bekräftades baserat på uppsatta kriterier. Precision och noggrannhet testades i repeterbarhetsförhållanden och vid fyra olika koncentrationsnivåer. De erhållna resultaten visade att metodens noggrannhet ökade med koncentration och var högst för 50 ppm, för nästan alla element. Den högsta precisionen (<2% RSD), för nästan alla element, erhölls för koncentrationen av 25 ppm. LOD-värdena var mellan 0.01 och 1.42 ppm medan beräknade LOQ-värden var mellan 0.04 och 4.73 ppm.

The paper describes the comparison and the difference of modern hydraulic fluids compared to conventional hydraulic fluids. A comparison of different base oil groups, solvent neutrals, group I and comparison with hydrotreated/hydroprocessed group II and/or group III base oils is presented. The influence on oxidation stability, elastomer compatibility, carbon distribution and physical properties is outlined.

The paper describes the comparison and the difference of modern hydraulic fluids compared to conventional hydraulic fluids. A comparison of different base oil groups, solvent neutrals, group I and comparison with hydrotreated/hydroprocessed group II and/or group III base oils is presented. The influence on oxidation stability, elastomer compatibility, carbon distribution and physical properties is outlined.

Environmentally friendly lubricants are in demand in response to the rising concerns and restrictive legislation that surround the use of mineral oil lubricants. One area of importance is understanding the service life of the environmentally friendly base oils of these non-toxic, biodegradable and renewable alternatives. The service life of a lubricant is directly influenced by its degradation behavior, especially oxidation.  In this research, selected environmentally friendly base oils; Glycerol, Rapeseed oil, Polypropylene glycol, Polyethylene glycol, Bis(di-2-ethyl hexyl) sebacate, Squalene and reference mineral oil; paraffin,  were subjected to thermo-oxidative ageing at 150oC. The changes in the chemical structures of the samples were followed using Spectroscopic, chromatographic, rheological and corrosivity studies. Tribological tests were also carried out to quantify the changes in these lubricants. The results obtained showed that the thermal oxidation affected the physicochemical properties and the lubricating ability of the base oils. However, each base oil degraded distinctly to the accelerated ageing conditions.