Kinetic Study of the Thermo-Oxidative Degradation of Squalane (C30H62) Modeling the Base Oil of Engine Lubricants

2009 ◽  
Vol 132 (3) ◽  
Author(s):  
Moussa Diaby ◽  
Michel Sablier ◽  
Anthony Le Negrate ◽  
Mehdi El Fassi
Keyword(s):  
Oxidative Degradation ◽  
Engine Oil ◽  
Ongoing Research ◽  
Base Oil ◽  
Rate Law ◽  
Tert Butyl ◽  
Oxidation Rates ◽  
Base Oils ◽  
Wide Range ◽  
Thermo Oxidative Degradation

On the basis of ongoing research conducted on the clarification of processes responsible for lubricant degradation in the environment of piston grooves in exhaust gas recirculation (EGR) diesel engines, an experimental investigation was aimed to develop a kinetic model, which can be used for the prediction of lubricant oxidative degradation correlated with endurance test conducted on engines. Knowing that base oils are a complex blend of paraffins and naphthenes with a wide range of sizes and structures, their chemistry analysis during the oxidation process can be highly convoluted. In the present work, investigations were carried out with the squalane (C30H62) chosen for its physical and chemical similarities with the lubricant base oils used during the investigations. Thermo-oxidative degradation of this hydrocarbon was conducted at atmospheric pressure in a tubular furnace, while varying temperature and duration of the tests in order to establish an oxidation reaction rate law. The same experimental procedures were applied to squalane doped with two different phenolic antioxidants usually present in engine oil composition: 2,6-di-tert-butyl-4-methylphenol and octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate. Thus, the effect of both antioxidants on the oxidation rate law was investigated. Data analysis of the oxidized samples (Fourier transform infrared spectroscopy and gas chromatography/mass spectrometry) allowed rationalization of the thermo-oxidative degradation of squalane. The resulting kinetic modeling provides a practical analytical tool to follow the thermal degradation processes, which can be used for prediction of base oil hydrocarbon aging. If experiments confirmed the role of phenolic additives as an effective agent to lower oxidation rates, the main results lie in the observation of a threshold temperature where a reversed activity of these additives was observed.

Kinetic Study of the Thermo-Oxidative Degradation of Squalane (C30H62) Modelling the Base Oil of Engine Lubricants

2009 ◽  
Author(s):  
Moussa Diaby ◽  
Michel Sablier ◽  
Anthony Le Negrate ◽  
Mehdi El Fassi
Keyword(s):  
Oxidative Degradation ◽  
Engine Oil ◽  
Ongoing Research ◽  
Base Oil ◽  
Rate Law ◽  
Tert Butyl ◽  
Oxidation Rates ◽  
Base Oils ◽  
Wide Range ◽  
Thermo Oxidative Degradation

On the basis of ongoing research conducted on the clarification of processes responsible for lubricant degradation in the environment of piston grooves in EGR diesel engines, an experimental investigation was aimed to develop a kinetic model which can be used for the prediction of lubricant oxidative degradation correlated to endurance test conducted on engines. Knowing that base oils are a complex blend of paraffins and naphtenes with a wide range of sizes and structures, their chemistry analysis during the oxidation process can be highly convoluted. In the present work, investigations were carried out with the squalane (C30H62) chosen for its physical and chemical similarities with the lubricant base oils used during the investigations. Thermo-oxidative degradation of this hydrocarbon was conducted at atmospheric pressure in a tubular furnace, while varying temperature and duration of the tests in order to establish an oxidation reaction rate law. The same experimental procedures was applied to squalane doped with two different phenolic antioxidants usually present in engine oil composition: 2,6-di-tert-butyl-4-methylphenol (BHT), and octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate (OBHP). Thus, the effect of both antioxidants on the oxidation rate law was investigated. Data analysis of the oxidized samples (FTIR spectroscopy, gas chromatography/mass spectrometry GC/MS) allowed to rationalize the thermo-oxidative degradation of squalane. The resulting kinetic modelling provides a practical analytical tool to follow the thermal degradation processes, which can be used for prediction of base oil hydrocarbon ageing. If experiments confirmed the role of phenolic additives as an affective agent to lower oxidation rates, the main results lay in the observation of a threshold temperature where a reversed activity of these additives was observed.

Thermo Oxidative Degradation Behavior of Jatropha Curcass L. Oil in the Presence of Antioxidant

2013 ◽  
Vol 393 ◽  
pp. 893-898
Author(s):  
Abdul Munir Hidayat Syah Lubis ◽  
Bambang Ari-Wahjoedi ◽  
Mustafar Sudin ◽  
Parman Setyamartana
Keyword(s):  
Thermo Gravimetric Analysis ◽  
Oxidative Degradation ◽  
Gravimetric Analysis ◽  
Jatropha Oil ◽  
Base Oil ◽  
Long Time ◽  
First Onset ◽  
Lower Temperature ◽  
Oxidative Behavior ◽  
Thermo Oxidative Degradation

Seed oils were used as base oil since long time ago. However their usage is limited due to its thermo oxidative and cold flow properties. Chemical modification and addition of proper additives are known to be able to improve these limitations. In this work, the effect of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate as potential hindered phenol antioxidant (HPAO) on thermo-oxidative degradation of jatropha oil was investigated. 1, 3, 5 wt% of antioxidant was dissolved into jatropha oil and their thermo-oxidative behavior was studied by using thermo-gravimetric analysis method under oxidative environment. The addition of the HPAO was found to accelerate the occurrence of thermal degradation first onset of jatropha oil. This factor corresponds to reaction of the compound during heating that reduces the peroxides formation to a less-reactive alcohol which is more volatile, thus making the first onset temperature occurred at a lower temperature.

Influence of thermo-oxidative degradation on the biodegradability of lubricant base oils

2008 ◽  
Vol 25 (2) ◽  
pp. 75-83 ◽  
Author(s):  
Elżbieta Beran ◽  
Magdalena Łoś ◽  
Aleksandra Kmiecik
Keyword(s):  
Oxidative Degradation ◽  
Base Oils ◽  
Thermo Oxidative Degradation

scholarly journals Thermogravimetric analysis in the synthetic engine oil 5W-30

2017 ◽  
Vol 170 (3) ◽  
pp. 188-192
Author(s):  
Ewa ROSTEK ◽  
Maciej BABIAK
Keyword(s):  
Thermogravimetric Analysis ◽  
Temperature Regime ◽  
Ir Spectrum ◽  
Oxidative Degradation ◽  
Engine Oil ◽  
Flow Rates ◽  
Engine Oils ◽  
Different Temperatures ◽  
Ftir Spectrometer ◽  
Thermo Oxidative Degradation

Engine oils undergo oxidative degradation and wears out during service. Hence it is important to characterize ageing of engine oils at different simulated conditions to evaluate the performance of existing oils and also design new formulations. This work focuses on characterizing the thermo-oxidative degradation of synthetic engine oils 5W-30. Thermogravimetric analysis of fresh and degraded oil samples at different temperatures and ageing intervals was performed in STA 449 F3 Jupiter® coupled with the FTIR spectrometer. The temperature regime provided that the samples were heated to the temperature of 600°C at the heating rate of 10 K/min. Gases (nitrogen, argon) were used with flow rates of 60 mL/min. The results, along with discussion, are presented in graphs – TG curves and IR spectrum

Study on the Effect of Hydrogenated Lubricant Base Oil Composition to Its Oxidation Stability

2005 ◽  
Author(s):  
Xiao Li Hu ◽  
Hui Dong Wang
Keyword(s):  
High Temperature ◽  
High Temperature Oxidation ◽  
Oxidation Stability ◽  
Engine Oil ◽  
Oil Composition ◽  
Temperature Oxidation ◽  
Base Oil ◽  
Base Oils ◽  
Thermo Stability ◽  
Model Oil

In this paper, we studied the high temperature oxidation stability of hydrogenated lubricant base oils used in automobile engine oil formations. Different oil from Daqing, Lanzhou and Kelamayi were investigated, and a hydro-isomerised poly alpha olefin oil PAO-6 produced by Mobile company was used as model oil. The influence of aromatic hydrocarbon, sulfur and nitrogen content of the base oils to their oxidation stability was investigated. The result indicated that, the high temperature oxidation stability of all these base oil was not good, but their thermo-stability was very good.

Vegetable Oils as Base Oil for Industrial Lubricants: Evaluation Oxidative and Low Temperature Properties Using TGA, DTA and DSC

2005 ◽  
Author(s):  
N. H. Jayadas ◽  
K. Prabhakaran Nair ◽  
G. Ajithkumar
Keyword(s):  
Low Temperature ◽  
Vegetable Oils ◽  
Thermo Gravimetric Analysis ◽  
Oxidative Degradation ◽  
Gravimetric Analysis ◽  
Scanning Calorimetry ◽  
Thermo Gravimetric ◽  
Thermal Stabilities ◽  
Base Oil ◽  
Base Oils

In this paper oxidative degradation of saturated and unsaturated vegetable oils is studied by thermo gravimetric analysis (TGA) and differential thermal analysis (DTA) and their low temperature properties are studied by differential scanning calorimetry (DSC). Both non-isothermal and isothermal thermo gravimetric analysis procedures are used for the study. The onset temperatures of oxidative degradation and weight gain in isothermal TGA are taken as measures of oxidative and thermal stabilities. Three vegetable oils namely coconut oil, sesame oil and sunflower oil with varying degree of un-saturation are selected for the study. The results are found to agree with reported results obtained by conventional methods. Several standard methods are currently available for determining the oxidative and low temperature properties of base oils. These methods are extremely time-consuming and data reproducibility between laboratories is poor. TGA, DTA and DSC are excellent tools to evaluate base oils in respect of their oxidative and low temperature behavior in that they produce results quickly, reproducibly and the sample requirement is very low.

Synthesis and evaluation of amines/phenolics antioxidant for TMPTO base oil

2019 ◽  
Vol 72 (1) ◽  
pp. 46-53 ◽  
Author(s):  
Wen Zhan ◽  
Dan Jia ◽  
YongLiang Jin ◽  
HaiTao Duan ◽  
Jian Li ◽  
...  
Keyword(s):  
Design Methodology ◽  
Early Stage ◽  
Oxidative Degradation ◽  
Basic Structure ◽  
Phenolic Antioxidants ◽  
Total Acid ◽  
Scanning Calorimetry ◽  
Content Type ◽  
Base Oil ◽  
Thermo Oxidative Degradation

Purpose The purpose of this paper is to synthesize amines/phenolic antioxidants by a new method and to characterize the influence of antioxidants on thermo-oxidative degradation in trimethylolpropane trioleate (TMPTO) base oil. Design/methodology/approach The molecule structures of antioxidants and lubricants were confirmed using Fourier transform infrared spectroscopy (FTIR). The oxidative stability of antioxidants and lubricants was evaluated by pressurized differential scanning calorimetry (PDSC). Findings These findings suggested that butyl-octyl-diphenylamine has obvious advantage on kinematic viscosity inhibition, and amine-phenol combination antioxidant has a slightly better suppression of total acid in TMPTO under thermal oxidation at 200°C for 96 h. The FTIR characterizations showed that all antioxidants could protect the basic structure of TMPTO in the early stage of thermal degradation. Originality/value Under the action of butyl-octyl-diphenylamine, the dehydrogenation of TMPTO is easily met with the alkenyl hydrogen = C–H bond in the unsaturated C = C. Meanwhile, as octadecyl 3-(3, 5-di-tert-butyl-4-hydroxyphenyl)propionate protects TMPTO, the unsaturated C = C bond in the base oil molecule easily breaks down during transition.

The Influence of Ultra-Low Concentrations of Potassium Anphen on the Bioenergetic Characteristics of Mitochondria

2020 ◽  
Vol 16 (4) ◽  
pp. 537-542
Author(s):  
Zhigacheva Irina ◽  
Volodkin Aleksandr ◽  
Rasulov Maksud
Keyword(s):  
Functional State ◽  
Membrane Lipids ◽  
Biological Effects ◽  
Dose Dependence ◽  
Stress Factors ◽  
Mitochondrial Membranes ◽  
Oxidation Rates ◽  
Pea Seedlings ◽  
Low Concentrations ◽  
Wide Range

Background: One of the main sources of ROS in stress conditions is the mitochondria. Excessive generation of ROS leads to oxidation of thiol groups of proteins, peroxidation of membrane lipids and swelling of the mitochondria. In this regard, there is a need to search for preparationsadaptogens that increase the body's resistance to stress factors. Perhaps, antioxidants can serve as such adaptogens. This work aims at studying the effect of antioxidant; the potassium anphen in a wide range of concentrations on the functional state of 6 day etiolated pea seedlings mitochondria (Pisum sativum L). Methods: The functional state of mitochondria was studied per rates of mitochondria respiration, by the level of lipid peroxidation and study of fatty acid composition of mitochondrial membranes by chromatography technique. Results: Potassium anphen in concentrations of 10-5 - 10-8 M and 10-13-10-16 prevented the activation of LPO in the mitochondrial membranes of pea seedlings, increased the oxidation rates of NAD-dependent substrates and succinate in the respiratory chain of mitochondria that probably pointed to the anti-stress properties of the drug. Indeed, the treatment of pea seeds with the preparation in concentrations of 10-13 M prevented the inhibition of growth of seedlings in conditions of water deficiency. Conclusion: It is assumed that the dose dependence of the biological effects of potassium anphen and the manifestation of these effects in ultra-low concentrations are due to its ability in water solutions to form a hydrate containing molecular ensembles (structures).

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