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Afton Catalyst Test Update. Report to ILSAC/OIL ESCIT Panel May 4, 2006. Primary Goal of Afton Test Development. To determine the relevance of PEI 250 on phosphorus throughput and the impact, if any, on catalyst poisoning. Testing Conditions Update.
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Afton Catalyst Test Update Report to ILSAC/OIL ESCIT Panel May 4, 2006
Primary Goal of Afton Test Development • To determine the relevance of PEI250 on phosphorus throughput and the impact, if any, on catalyst poisoning
Testing Conditions Update • Version II of ACT has been in-use since 01/06 • Conditions were adjusted to increase impact of phosphorus volatility and throughput • Higher speed • 1800 rpm to 2000 rpm • Higher oil temp • 120°C to 150°C • Higher coolant temp • 100°C to 122°C • Larger oil charge • 3015 gm to 4500 gm
Summary of Afton Catalyst Test, V2 • 240-hours • 10 oil changes (every 24-hours) • Steady-state • Catalyst inlet temp: ~ 550°C • Oil temperature: 150°C • Coolant temperature: 122°C • Engine Speed: 2000 rpm • Engine Map: 65.5 kPa • Oil Charge: 4500 grams • Single Ford Light-off Catalyst mounted on Y-pipe • Pre and post-test emissions performed on engine using slight-rich AFR (0.005 offset)
Example showing new catalyst conversion efficiency curves “T50” Temp where 50% CE occurs
Test Design • Two pairs of oils • GF-4 chemistry with same phos concentration • ZDDP “A” (PEI250=90) • ZDDP “B” (PEI250=11) • GF-2 chemistry from Afton/Ford/Delphi field test – SAE 2002-01-2680 • Same ZDDP additive • Fully formulated oil (PEI250 =15) – “Oil 32” • Oil without detergent (PEI250 =45) – “Oil 33”
New and Aged Oil ICP Analyses FT Oil 32 FT Oil 33 NEW AGED
Percent Change in Elemental Concentration and Oil Consumption Oil Consumption Note: Avg. OC for 21NOACK oils is ~50% greater.
Calculated Phosphorus Depletion From SAE 2002-01-2680 Calculation for % phos depletion: Phosnew/ ((Znhrx/Znnew)xPhosnew)-Phoshrx Calculated phosphorus depletion*
Loss of Conversion Efficiency (T50) Increase in temperature where 50% conversion efficiency occurs GF-2-Style FT Oils GF-4-Style PEI Comparison Oils • Oil 33 (RB10358) had worse overall performance • High PEI RB10331 was not appreciably different from low PEI RB10332
Analysis of Blowby Volatile Organic Matter • Oil RB10331 with high PEI250 carried over more calcium-based detergent. • SAE 920654 speaks to inhibition of phosphorus deposition resulting from use of alkaline-earth metal detergents.
Phosphorus Depletion Mechanisms • Analysis of blowby condensate suggests at least three mechanisms for phosphorus depletion occurring in the engine • Volatilization of phosphorus from bulk oil • Volatilization of phosphorus from cylinder wall oil film • Consumption of oil mist • Phosphorus throughput to the catalyst is a complicated mechanism not easily simulated
Conclusions • No strong evidence that PEI250 relates to increased phosphorus throughput and resulting catalyst poisoning • Blowby from the engine contains other additive elements in addition to phosphorus • Alkaline-earth metal detergents are carried out with blowby in high PEI250 oil and perhaps have an impact on depostion within the catalyst. • Observation in SAE 2002-01-2680 about elevated PEI250 leading to increased catalyst poisoning is most likely related to lack of detergent.