Synthesis and Evaluation of Some Detergent/Dispersant Additives for Lube Oil

With increasing demands being placed on lubricants for automotive engines and transmissions, it has been necessary to work to improve the function of these lubricants. Modern lubricants are formulated from a range of base fluids and chemical additives to enhance their actions or to add new properties. In this study we have confined ourselves to the study of the detergent/dispersant type of additives based on preparation of polyisobutylene succinic anhydride (PIBSA) and then the reaction of PIBSA with different polyethylene glycols and the amination of the products by different polyamines. The compositions of the prepared compounds were determined by molecular weight, I.R. and H-NMR spectroscopy. The efficiency of the prepared compounds as antioxidants and detergents/dispersants was investigated. It was found that the prepared compounds have very good dispersancy power and the efficiency increases by increasing the number of –NH groups in the prepared compounds and by increasing the molecular weight of the polyethylene glycols.     

Preparation and Evaluation of Some Lube Oil Additives Based on Polyethylene Glycol

Among the various additives employed in modern engine oils, one of the most important is the type that acts to prevent an accumulation of sludge in the crankcase and on the cylinder walls, thereby preventing sticking of piston rings and the formation of varnish-like coatings on the pistons and cylinder walls. Because of their general function of maintaining a clean engine, additives of this nature are termed detergents although it is now understood that they have little utility in cleaning a dirty engine, but by virtue of dispersing activity, prevent engine fouling. A main source of deposits is the oxidation of oil in high temperature, which can be reduced by using antioxidants. This work was limited to the preparation and characterization of different types of polyethylene glycol palmitate with different molecular weights and amination of the prepared esters with tetraethylenepentamine. The efficiency of the prepared compounds as detergents/dispersants and antioxidants was investigated and the effect of the prepared additives on other properties of lube oil was also studied. It was found that all the prepared compounds act as detergents/dispersants and antioxidant additives with no effect on the viscosity index and pour point of the lube oil.     

Effect of oil type on stability of high internal phase water-in-oil emulsions with super-cooled internal phase

This study considered the stability and rheology of a type of high internal phase water-in-oil emulsions (W/O) emulsion. The aqueous phase of the emulsions is a super-cooled inorganic salt solution. The oil phase is a mixture of industrial grade oils and stabilizer. Instability of these systems manifests as crystallization of the metastable dispersed droplets with time. This work focused on the effects of oil polarity and oil viscosity on the stability of these emulsions. Ten types of industrial oils, covering the viscosity range 1.4–53.2?cP, and with varying polarity, were used in combination with polymeric poly(isobutylene) succinic anhydride (PIBSA) and sorbitan monooleate (SMO)-based surfactants. The effect of oil relative polarity on rheological parameters of the emulsion was evident mainly in the emulsions stabilized using polymeric surfactant, whereas the oil viscosity did not show any significant effect. The optimum stability of the emulsions stabilized with SMO was achieved using high polar oils with a viscosity of 3?±?0.5?cP. However, when using the PIBSA surfactant, the best emulsion stability was achieved with low polar, high viscosity oils.     

Lubricating Oil Additives Based on Polyalkylpolyamines

This work is confined to the preparation and characterization of additives. These additives are based on the reaction of polyisobutylene with different ethanolamine and then amination with tetraethylenepentamine. The molecular weights of the prepared compounds were determined by gel permeation chromatography (GPC). The efficiency of the prepared compounds as antioxidant and detergent/dispersantadditives for lube oil was studied. It was found that the efficiency increases with increasing the molecular weight and -NH- group of the prepared compounds.     

The effects of metallic catalysts on light crude oil oxidation in limestone medium

In this study, 28 experiments were performed to study the effects of metallic additives on light crude oil oxidation in limestone medium. Karakuş and Beykan crude oils from Turkish oil fields were used. The metallic additives were ferric chloride (FeCl₃), copper chloride (CuCl) and magnesium chloride (MgCl₂·6H₂O). The mixture of aqueous solutions of three metallic salts with limestone and the crude oils was subjected to a controlled heating schedule under a constant flow rate of air. The produced gas was analysed for its oxygen and carbon oxides contents.The results of reaction kinetics showed that the molar CO₂/CO ratio values of fuel combustion increased when additives were added. A decrease in the atomic H/C ratio with an increase in temperature was observed for all runs. The reaction order, m in Arrhenius equation increases as concentration of copper and magnesium chloride additive increases but decreases as ferric chloride additive increases in both crude oils. It is observed that the metallic additives except ferric chloride decreased the Arrhenius constant, Ar, for both crude oils.As concentration of ferric chloride increases the activation energy of Karakuş crude oil increases while activation energy of Beykan crude oil decreases. The copper chloride additive shows same trend for both crude oils. The 1.0 mol% concentration decreases the activation energies. The 2.0 mol% magnesium chloride increases the activation energy of Karakuş crude oil while decreases the activation energy of Beykan crude oil more than 1.0 mol% does.For Karakuş crude oil, the oxygen consumption curves of 2.0 mol% of metallic additives show one peak. There is similar behavior between runs with 1.0 mol% of ferric chloride and magnesium chloride and runs with no additive, but the oxidation reaction peaks with metallic salts at both concentrations occurs at lower temperatures. For Beykan crude oil, all the additives lower the peak temperature when they are compared to standard run. The trends of the curves are actually the same. Copper chloride shows one peak with the 1.0 and 2.0 mol% runs for both crude oils.     

Additives from aromatic extracts

Aromatic extract residues, as by-products, are accumulated in local refineries through the refining of lubricating oils. These residues are dealt with as low economic value products, even their disposal imposes serious problems to the refineries. Therefore, the present work is aimed at upgrading these residues by using them to synthesis some different petroleum additives, e. g. antioxidants, ashless dispersant additives, pour point depressants and flow improvers for crankcase lubricating oils and fuels. Antioxidants are synthesised by reacting mono-aromatics with phosphorus pentasulphide (P₂S₅) in the presence of zince oxide (ZnO). Ashless dispersant additives are synthesised by reacting alkylated mono-aromatics (using chlorinated paraffin wax as alkylating agent) with formaldehyde solution (37%) in the presence of polyisobutylene succinimide. Pour point depressants and flow improvers are synthesised by acylating di-aromatics via a Friedel-Crafts' reaction. Comparative evaluation of the performance of the synthesised products with commercial additives showed their good efficiency.     

Performance of higher poly(alkyl lactate acrylate)s as viscosity modifiers in vegetable oils

Recently, bio-derived materials such as vegetable oils are significantly employed in lubricating oil formulations due to its high flash point, high lubricity, low evaporation loss, renewability, biodegradability, and eco-friendliness when compared to mineral oil. We investigated the performance of seven poly(alkyl lactate acrylate)s as viscosity modifiers in two vegetable oils, namely, coconut oil and sunflower oil, which differ in the percentage of polar compounds and degree of unsaturation. Poly(alkyl lactate acrylate)s having alkyl as hexyl to dodecyl group in different concentrations between 1 and 2 wt% were added to coconut and sunflower oil and parameters such as thickening power or Q factor, kinematic viscosity (μ), and viscosity index (VI) were calculated. The μ values at 40°C and 100°C of vegetable oils studied were lower than commercially available SAE20W40 engine oil, but the VI of coconut and sunflower oil was higher by about 22%. Value of Q factor higher than 1, indicated that these poly(alkyl lactate acrylate)s were VI improvers. VI increased with increase in the polymer concentration in both the vegetable oils. The length of the alkyl side chain of these polymers and the polarity of vegetable oil had predominant effect in determining the values of VI of vegetable oils. By using these polymer additives, VI was improved by 85.5% in coconut oil and by 61.7% in sunflower oil. Varying the concentration and alkyl group of these additives, one can largely modify the viscosity ranges enabling them to be used in different lubricating applications.     

A Search for Ecofriendly Detergent/Dispersant Additives for Vegetable-Oil Based Lubricants

Carbonaceous deposits in automotive engines are the major problems associated with oil aging. Efficient detergents and dispersants have been used for several decades to solve this problem particularly in petroleum oils. But future lubricants and new engine hardware require development of new nontoxic detergent/dispersant additive technologies. Environmental concerns limit the formulation of the future lubricants. It requires not only the base oil to be ecofriendly but the additives also. In the present work, some of the potential ecofriendly chemical??s molecules were identified. Specific detergents applications along with effects of chemical modifications were evaluated by Blotters Spot and Panel Coker Tests. Among the studied compounds, the PIB (polyisobutylene) succinimides are showing promising results at lower temperature, while at higher temperature piperazine derivatives citrate and oleate have the best potential to be develop as ecofriendly detergent/dispersant additives.     

Synthesis of polymeric pour point depressants for Nada crude oil (Gujarat,India) and its impact on oil rheology

Five flow improvers have been synthesized to study rheological properties of Nada crude oil (Gujarat, India). Anhydride copolymers were prepared making use of the copolymerization of acrylates of different alkyls with maleic anhydride and the Poly (n-alkyl acrylates-co-N-hexadecylmaleimide) were prepared by the reaction of copolymer with hexadecylamine. The additives were purified and characterized by FTIR, GPC. The prepared polymeric additives shows dual function both as wax dispersants and flow improvers and all of them acts as good pour point depressants. Yield stress and the viscosity of the crude oil at different temperatures and concentrations of additives were evaluated by zero friction advanced rheometer AR-500 of TA instrument. Comparison of morphologies and structures of wax crystals or aggregates in waxy crude oils beneficiated with and without a PPD was also done by micro photographic studies which show the modification in wax crystal morphology due to additives.     

Effect of the doses and nature of vegetable oil on carbon black/rubber interactions: Studies on castor oil and other vegetable oils

The effects of additives in various vegetable oils on the physical, mechanical, and adhesion properties of carbon black/rubber compounds were studied. Various doses of castor oil and some other oils such as paraffin oil, vegetable oil 1, and cashew nut shell liquid (CNSL) at a fixed dose (1 phr) were used. With an increase in the castor oil content, the modulus, tear strength, and tensile strength increased, whereas the hardness and adhesive strength exhibited little variation up to 1 phr. Beyond 1 phr castor oil, the modulus, tear strength, and hardness decreased, whereas the adhesive and tensile strengths increased up to 2.5–3 phr and then decreased. Therefore, castor oil seemed to behave as a coupling agent up to 1 phr and as a coupling agent and a plasticizer in the range of 1–3 phr; beyond that, the main role of castor oil was plasticization. When various oils at a fixed dose (1 phr) were compared, it was found that the vegetable oils exhibited enhanced properties in comparison with those of paraffin oil. In addition, both of the unsaturated oils (castor oil and vegetable oil 1) enhanced physical and mechanical properties in comparison with saturated paraffin oil. CNSL exhibited the best adhesion properties against mild steel and galvanized iron substrates. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1574–1578, 2003     

Stability of a phenol‐enriched olive oil during storage

The use of an emulsifier to stabilize the phenolic compounds added in the preparation of an enriched olive oil was evaluated. Two emulsifiers, lecithin and monoglyceride, were studied. The results showed lecithin to be the most convenient, due to the increase in the value of the oxidative stability of the phenol‐enriched oils in relation to the enrichments prepared with monoglycerides. After that, the shelf life of the prepared oils was evaluated during a period of 256 days of storage at 25°C in the dark. Oil quality parameters, total phenolic content, bitterness index and oxidative stability were studied during the storage period. Additionally, the phenolic composition and antioxidant capacity (by using the ORAC assay) were evaluated at the end of the storage. The phenolic enrichment of the oils allowed the shelf life of the oils to be extended compared with the control (virgin olive oil without phenol addition), delaying the appearance of peroxides and improving their oxidative stability. In addition, the higher content of phenolic compounds in the oils at all stages of storage is desirable in order to increase the intake of these beneficial compounds. Practical applications : The preparation of phenol‐enriched olive oils with a higher phenolic content than the commercial virgin olive oils is of special interest to increase the ingestion of these healthy compounds the daily intake of which is limited due to the high caloric value of olive oil. There are two key points in the development of this product: (i) the dispersion and stabilization of the phenol extract in the oil matrix and (ii) the stability of the phenols in the prepared oils to guarantee the phenol concentration during their shelf life. It is important to study the use of emulsifiers to determine if they allow an improvement in the dispersion of the phenolic extract, and their stabilization in the final product. In addition, the emulsifiers could mask the bitter taste of the enriched oils, which is desirable to increase consumer acceptance of the enriched oil.     

Differences in Oxidative Stability,Sensory Properties,and Volatile Compounds of Pepper Aromatized Sunflower Oils Prepared by Different Methods during Accelerated Storage

The study aims to compare the differences in the oxidative stability, sensory properties, and volatile compounds during accelerated storage of pepper aromatized sunflower oil (PASO) samples prepared by maceration method (PASO-M), co-pressing method (PASO-C), and direct addition method (PASO-A), respectively. The results exhibit that their oxidative stability is in the relative order: PASO-A > PASO-C > PASO-M. Meanwhile, the PASO-A sample is the most preferable aromatized sunflower oil by consumers according to sensory analysis. In addition, a total of 83 volatile compounds are identified in the three PASO samples during the storage, and the principal component analysis (PCA) shows that their volatile compounds are quite different at the initial stage of the storage. Still, they are similar among each other from the middle of storage period. As consequence, the aromatized sunflower oil sample prepared by the direct-addition method during the storage possesses better oxidative stability and sensory attributes, and there is not much difference among their volatile compounds, indicating that the aromatized sunflower oil prepared by direct-addition method can be developed as promising aromatized sunflower oil. Practical applications: This study shows that aromatization increases oxidative stability and sensory properties of sunflower oil. By this way some sunflower oils with special sensory properties are obtained: special smell and taste, special color, etc. These peppers aromatized sunflower oils can be used to increase taste and smell in some dishes. For example, they can be used in some salads and some roast meats to give more taste and color.     

Detection of adulteration of sesame and peanut oils via volatiles by GC × GC–TOF/MS coupled with principal components analysis and cluster analysis

The method of headspace coupled with comprehensive two‐dimensional GC–time‐of‐flight MS (HS‐GC × GC–TOF/MS) was applied to differentiate the volatile flavor compounds of three types of pure vegetable oils (sesame oils, peanut oils, and soybean oils) and two types of adulterated oils (sesame oils and peanut oils adulterated with soybean oils). Thirty common volatiles, 14 particular flavors and two particular flavors were identified from the three types of pure oils, from the sesame oils, and from the soybean oils, respectively. Thirty‐one potential markers (variables), which are crucial to the forming of different vegetable oil flavors, were selected from volatiles in different pure and adulterated oils, and they were analyzed using the principal component analysis (PCA) and cluster analysis (CA) approaches. The samples of three types of pure vegetable oil were completely classified using the PCA and CA. In addition, minimum adulteration levels of 5 and 10% can be differentiated in the adulteration of peanut oils and sesame oils with soybean oils, respectively. Practical applications: The objective was to develop one kind of potential differentiated method to distinguish high cost vegetable oils from lower grade and cheaper oils of poorer quality such as soybean oils. The test result in this article is satisfactory in discriminating adulterated oils from pure vegetable oils, and the test method is proved to be effective in analyzing different compounds. Furthermore, the method can also be used to detect other adulterants such as hazelnut oil and rapeseed oil. The method is an important technical support for public health against profit‐driven illegal activities.     

Supplementation of oils with oleanolic acid from the olive leaf (olea europaea)

A method was studied for utilization of olive leaf, which is a byproduct of olive tree pruning and olive oil production. Our strategy involves two stages. The first is a simple procedure for isolating oleanolic acid, a compound with known biological activity. The second stage involves supplementation of different types of oil with this triterpenic acid. Two protocols were used for incorporating this acid into oils, either as a solid or as a solution, at concentrations from 200 to 1000 ppm. Oleanolic acid in the prepared oils was quantified by gas liquid chromatography. At the concentrations analyzed, the oleanolic acid content measured in all oil samples was equal to the amount added (p <0.05). No significant difference was observed (p <0.05) between the two supplementation procedures in any of the oils.     

Superlow friction and diffusion behaviors of a steel-related system in the presence of nano lubricant additive in PFPE oil

The lubrication performances of diamond like carbon (DLC) films were investigated by a ball-on-disc tribometer under perfluoropolyether (PFPE) oil lubrications. The influence of nano lubricant additives in PFPE oil on the tribological properties of DLC films was evaluated. The experimental results show that the solid-liquid synergy lubrication is beneficial to improve the tribological properties of the steel-related friction system and the tribological properties of the friction pair are significantly influenced by lubrication modes and the types and contents of nano lubricant additives under PFPE oil lubrication. The friction system exhibits super low friction behaviors under PFPE oil with nano MoS₂ lubricant additive lubrication due to the excellent compatibility of nano MoS₂ additives with PFPE oil. Coefficient of friction (CoF) of the friction system is as super low as 0.02 under PFPE oil with 0.2?wt.% nano MoS₂ additive lubrication. Superlow friction mechanism is attributed to the pointlike contact of nano MoS₂ additive as soft phase and the excellent diffusion behaviors of nano MoS₂ additives in PFPE oil. The potential usefulness of nano MoS₂ particles as the lubricant additives in PFPE oil for the steel/DLC films has been demonstrated.     

Sperm oil replacements: Synthetic wax esters from selectively hydrogenated soybean and linseed oils

Synthetic wax esters with properties similar to those of sperm whale oil have been prepared entirely from soybean and linseed oils. the synthesis required: (a) selective hydrogenation of the oils with copper-on-silica gel catalyst, (b) hydrogenolysis of fatty acids to fatty alcohols with copper-cadmiumchromium catalyst, and (c) esterification of hydrogenolysis products to yield predominantly long chain fatty esters which contained unsaturation in both the alcohol and acid moieties. Similarity of physical and chemical properties indicate that these wax esters are possible replacements for sperm oil. After sulfurization, the wax esters also have potential as extreme pressure lubricant additives.     

高分散稳定纳米金刚石润滑油的制备及其摩擦学性能

为了改善纳米金刚石颗粒(NDPs)在抗磨液压油(AHO)中的分散性,制备了酸氧化?高温热处理的NDPs (T-NDPs),将其与添加剂(油胺、聚异丁烯丁二酰亚胺T154和高碱值合成磺酸钙T106)混合后加入AHO中,制得含T-NDPs的AHO。用FESEM及Zeta电位仪、FT-IR和静态沉降法对其分散性进行表征,用四球摩擦磨损试验机、3D激光扫描显微镜和SEM/EDS对含T-NDPs的AHO的摩擦学性能和磨痕区域进行了分析。结果表明,酸氧化?高温热处理后,NDPs的平均粒径从270.2 nm降至153.5 nm,吸附添加剂后的T-NDPs的平均粒径为101.5 nm,添加剂可提高T-NDPs的油溶性并抑制其团聚,因而含T-NDPs的AHO具有良好的分散稳定性;T-NDPs含量为0.04wt%时,AHO的摩擦系数和磨斑直径比不加T-NDPs时分别降低13.2%和17.8%;T-NDPs作为润滑添加剂的减摩抗磨功效归因于其在摩擦界面起到支撑和滚动轴承的作用及在摩擦副表面参与润滑膜形成。     

Lubricants and lubricant additives: III. Performance characteristics of some thioacetate,phosphorodithioate, and hexachlorocyclopentadiene derivatives of stearic acid amides and esters

A number of N-mono, N,N-disubstitured amides, and esters of substituted fatty acids have been prepared and evaluated as base lubricants and lubricant additives for paraffin (S-105) or diester (DOS) base oils. The effect of acetylthio, phosphorodithio, thio, chloro, and bromotrichloromethyl substituents, as well as hexachlorocyclopentadiene adducts upon performance as antiwear and extreme-pressure lubricants was investigated. Sulfurized 1,4-bis(pentachlorostearoyloxy)-2-butene was most effective in extreme-pressure (EP) tests, both neat and as an additive for S-105 and DOS base oils. Several of the phosphorodithio derivatives have good antiwear properties when formulated in one or both of the base oils, and were also fair EP additives. Of the addition compounds evaluated in this study, the phosphorodithio derivatives offer the most promise for development as antiwear additives for both paraffin and diester base oils. The sulfurized products offer the most promise as EP additives.     

Alterations in picual extra virgin olive oils under different storage conditions

Storage conditions can affect the stability of extra virgin olive oil, with adverse results on quality. The aim of this study is to examine changes in the chemical composition and sensory characteristics of the oil resulting from prolonged storage at different temperatures and depending on the type of container. The influence on the quality of the oil was also considered, based on the analysis of quality parameters, the total phenol contents, changes in minority compounds, the variation of the trolox equivalent antioxidant capacity values (TEAC) and sensory features. At both room temperature (RT) and refrigerated temperature, all container types had the same surface area of exposure to light and air. All the oils stored showed losses in both qualitative properties and minor components, as well as antioxidant capacity and sensory features. This was especially true for oils stored in polyethylene terephthalate and glass, but less so for those stored in Tetra‐Brik®.     

Structural Assignment of Commercial Polyisobutylene Succinic Anhydride-based Surfactants

Concentration of the surface active agents in industrial products is a common source of error. In order to compare the efficiency of a number of polyisobutylene succinic anhydride (PIBSA) based surfactants, their concentration needs to be determined with a fair degree of accuracy. Industrial samples of the monoethanolamine adduct of PIBSA (PIBSA-MEA) concentrate were used for chromatographic separation of the functionalized surfactant from the sample matrix. Complete spectroscopic assignments were based on detailed analysis of all the precursors and of the purified mixture of structural isomers. The structures of the double bond isomers were consistent with the expected addition products of the classic Alder-ene reaction-derived PIBSA. The carbon–carbon connectivity of the succinamide head group to the bulky polymer tail of PIBSA-MEA was more complicated than previously thought, pointing towards regioselectivity in the nucleophilic substitution of PIBSA. By analogy, further structural assignments of two other surfactants, branded as PIBSA-IMIDE and PIBSA-UREA were made from the spectroscopic data recorded on crude industrial samples. Detailed nuclear magnetic resonance (NMR) assignments for all three surfactants reported here were utilized to develop a semi-quantitative ¹³C-NMR based method for the estimation of the amount of the functionalized surfactant relative to the total PIB content in the industrial concentrates. The results highlight common sources of structure- and concentration-dependent errors in high internal phase emulsion formulations.