A research tool has been developed that utilizes the Thermo-Oxidation Engine Oil Simulation Test (TEOST) MHT-4 to collect information on engine oil oxidation and deposit formation. The technique capitalizes on the t...A research tool has been developed that utilizes the Thermo-Oxidation Engine Oil Simulation Test (TEOST) MHT-4 to collect information on engine oil oxidation and deposit formation. The technique capitalizes on the traditional TEOST features as a deposit formation test, but also generates additional oxidation information by monitoring peak increase in the carbonyl region of the Fourier Transform Infrared Spectrum (FT-IR) of TEOST used oils and volatiles. The data on overall oxidation and deposit formation is used to generate a "robustness" model for modern engine oil degradation. The tool is used to study low phosphorus Group Ⅱ passenger car engine oils formulated with different types of antioxidants and a molybdenum dithiocarbamate (MoDTC). The model shows that improved oxidation and deposit control can be achieved by formulating with the molybdenum compound, and that the most effective stabilization system is composed of the organo-molybdenum compound,an alkylated diphenylamine (NDPA), and the hindered phenolic antioxidant 4,4′-methylenebis(2,6-di-tert-butylphenol) (MBDTBP).展开更多
Phosphorus is known to poison the exhaust gas catalysts used to control emissions in modern gasoline-fueled passenger car vehicles.Phosphorus volatility has been studied by others as a potential issue related to the c...Phosphorus is known to poison the exhaust gas catalysts used to control emissions in modern gasoline-fueled passenger car vehicles.Phosphorus volatility has been studied by others as a potential issue related to the compatibility of modern engine oils with exhaust gas catalysts using a modified version of the ASTM D5800(Noack) test as well as the Sequence ⅢG engine test(ASTM D7320).The level of phosphorus volatility in these tests has been shown to be strongly affected by the chemistry of the zinc dialkyldithiophosphate(ZDDP) used in the engine oil formulation.The TEOST MHT-4 test(ASTM D7097) is a high temperature deposit test currently included in the ILSAC GF-4 specification.This bench test simulates the oxidation and deposit-forming characteristics of engine oils in the hot zones of modern high-performance engines and,therefore,was chosen by the author(s) as a tool to investigate differences in phosphorus volatility of modern engine oils.Our investigations demonstrate that the TEOST MHT-4 test is capable of measuring phosphorus volatility of engine oils with very good discrimination and precision;it may be considered for use in future ILSAC standards(e.g.GF-5).展开更多
文摘A research tool has been developed that utilizes the Thermo-Oxidation Engine Oil Simulation Test (TEOST) MHT-4 to collect information on engine oil oxidation and deposit formation. The technique capitalizes on the traditional TEOST features as a deposit formation test, but also generates additional oxidation information by monitoring peak increase in the carbonyl region of the Fourier Transform Infrared Spectrum (FT-IR) of TEOST used oils and volatiles. The data on overall oxidation and deposit formation is used to generate a "robustness" model for modern engine oil degradation. The tool is used to study low phosphorus Group Ⅱ passenger car engine oils formulated with different types of antioxidants and a molybdenum dithiocarbamate (MoDTC). The model shows that improved oxidation and deposit control can be achieved by formulating with the molybdenum compound, and that the most effective stabilization system is composed of the organo-molybdenum compound,an alkylated diphenylamine (NDPA), and the hindered phenolic antioxidant 4,4′-methylenebis(2,6-di-tert-butylphenol) (MBDTBP).
文摘Phosphorus is known to poison the exhaust gas catalysts used to control emissions in modern gasoline-fueled passenger car vehicles.Phosphorus volatility has been studied by others as a potential issue related to the compatibility of modern engine oils with exhaust gas catalysts using a modified version of the ASTM D5800(Noack) test as well as the Sequence ⅢG engine test(ASTM D7320).The level of phosphorus volatility in these tests has been shown to be strongly affected by the chemistry of the zinc dialkyldithiophosphate(ZDDP) used in the engine oil formulation.The TEOST MHT-4 test(ASTM D7097) is a high temperature deposit test currently included in the ILSAC GF-4 specification.This bench test simulates the oxidation and deposit-forming characteristics of engine oils in the hot zones of modern high-performance engines and,therefore,was chosen by the author(s) as a tool to investigate differences in phosphorus volatility of modern engine oils.Our investigations demonstrate that the TEOST MHT-4 test is capable of measuring phosphorus volatility of engine oils with very good discrimination and precision;it may be considered for use in future ILSAC standards(e.g.GF-5).
