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This study explores the degradation mechanisms of hydrocarbon base fluids at high temperatures, focusing on chemical reactions, viscosity modeling, and oxidation products. It provides insights into the impacts of oxidation on viscosity and the formation of polar and volatile compounds.
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The Degradation of Hydrocarbons Base Fluids at Elevated Temperatures STLE 2006: Calgary 7th- 11th May 2006 Moray S. Stark,* John R. Lindsay Smith, Julian J. Wilkinson Department of Chemistry, University of York, York YO10 5DD, UK Department of Chemistry
The Degradation of Hydrocarbons Base Fluids at Elevated Temperatures STLE 2006: Calgary 7th- 11th May 2006 Moray S. Stark,* John R. Lindsay Smith, Julian J. Wilkinson Department of Chemistry, University of York, York YO10 5DD, UK mss1@york.ac.uk www.york.ac.uk/res/gkg
The Degradation of Hydrocarbons Base Fluids at Elevated Temperatures • Chemical Mechanisms of Base Fluid Oxidation • Viscosity Modelling of Oxidised Base Fluid Department of Chemistry
Models of Hydrocarbon Base-Fluids No. of Carbons XHVI™ 8.2 (average)39 (random example) Department of Chemistry
Models of Hydrocarbon Base-Fluids No. of Carbons XHVI™ 8.2 (average)39 Hexadecane 16 (random example) Department of Chemistry
Traditional Alkane Oxidation Mechanism Department of Chemistry
Traditional Alkane Oxidation Mechanism Department of Chemistry
Traditional Alkane Oxidation Mechanism Department of Chemistry
Traditional Alkane Oxidation Mechanism Department of Chemistry
Traditional Alkane Oxidation Mechanism Department of Chemistry
Traditional Alkane Oxidation Mechanism Department of Chemistry
Models of Hydrocarbon Base-Fluids No. of Carbons XHVI™ 8.2 (average)39 Hexadecane 16 (random example) Department of Chemistry
Models of Hydrocarbon Base-Fluids No. of Carbons XHVI™ 8.2 (average)39 Hexadecane 16 Pristane 19 (random example) Department of Chemistry
Models of Hydrocarbon Base-Fluids No. of Carbons XHVI™ 8.2 (average)39 Hexadecane 16 Pristane 19 Squalane 30 (random example) Department of Chemistry
Tertiary Carbons in Base-Fluids S. McKenna, M. Casserino, K. Ratliff, Comparing the Tertiary Carbon Content of PAO’s and Mineral Oils Presentation, STLE Annual Meeting, Houston, 2002
Tertiary Carbons in Base-Fluids S. McKenna, M. Casserino, K. Ratliff, Comparing the Tertiary Carbon Content of PAOs and Mineral Oils Presentation, STLE Annual Meeting, Houston, 2002
Bench-Top Reactors Department of Chemistry
Oxidation of Branched Alkanes : GC Analysis Pristane Oxidation: 1000 mbar O2, 170 ºC, 20 minutes GC conditions: ZB-5 column, 50-340 ºC, 6 ºC min-1 Product Identification: EI-MS and CI-MS time (min) Department of Chemistry
Oxidation of Branched Alkanes : Alcohols e.g. { Department of Chemistry
Oxidation of Pristane : Tertiary Alcohols Department of Chemistry
Oxidation of Pristane : Secondary Alcohols e.g. { Department of Chemistry
Oxidation Products : Alcohols, Pristan-2-ol Department of Chemistry
Oxidation Products : Alcohols, Pristan-6-ol Department of Chemistry
Oxidation Products : Secondary Alcohols e.g. Department of Chemistry
Oxidation Products : Ratio of Alcohols e.g. Department of Chemistry
Oxidation Products : Ratio of Alcohols e.g. Department of Chemistry
Formation of Alcohols Department of Chemistry
Formation of Alcohols Department of Chemistry
Formation of Volatile Products Department of Chemistry
Formation of Volatile Products + + RH Department of Chemistry
Formation of Volatile Products + + RH Department of Chemistry
Formation of Volatile Products + + RH Department of Chemistry
Oxidation of Branched Alkanes : Pristanones e.g. { Department of Chemistry
Formation of Volatile Ketones and Alkanes Department of Chemistry
Formation of Volatile Ketones and Alkanes Department of Chemistry
Formation of Volatile Ketones and Alkanes + Department of Chemistry
Reactions of Alkyl Radicals Department of Chemistry
Reactions of Alkyl Radicals Department of Chemistry
Reactions of Alkyl Radicals Department of Chemistry
Reactions of Alkyl Radicals Department of Chemistry
Reactions of Alkyl Radicals Department of Chemistry
Formation of Volatiles : Lactones { Department of Chemistry
Formation of Volatiles : Lactones { Department of Chemistry
Lubricant Viscosity Increase During Use Paris Taxis Department of Chemistry
Viscosity Increase due to Lubricant Degradation Due to Formation of: • Polar Products Alcohols, Carboxylic Acids, etc. • Polymeric Products Dimers, Trimers, etc. of Base Fluid • Insoluble Products Aggregating Particles e.g. Soot, Micelles of Highly Polar Products Department of Chemistry
Viscosity Increase due to Lubricant Degradation Conditions : Pristane (tetramethylpentadecane) Oxidation in Flow Reactor Continuous O2 flow, Sampling at 6 minutes, 150 - 210 ºC Department of Chemistry
Viscosity Modelling : Effect of Polar Products • dodecane - docecanol model mixtures + Department of Chemistry
Viscosity Modelling : Effect of Polar Products • dodecane - docecanol model mixtures + Department of Chemistry
Viscosity Modelling: Effect of Polar Products • dodecane - docecanol model mixtures + Department of Chemistry
Conclusions • Chemical Mechanisms for Formation of • Polar Products • Volatile Products • Viscosity Increase during Lubricant Oxidation NOT due to Polar Oxidation Products Future Work • Quantify Polymeric Products • Examine Consequent Viscosity Change Department of Chemistry