dedicated to innovative catalyst research equipment that saves resources and expenditure
Introduction Dr Andrew Woods (CEO of Catagen Ltd) A Queen s University, Belfast Spin Out Business (Based in Northern Ireland) SAE Snowmobile Chalk Talk: Aging and Characterisation of Catalytic Converters 2
Contents Meeting the Challenge Emissions Standards Worldwide History of Catalytic Converters and Government Legislation Emissions Durability in Recreational Vehicles Mechanisms of Catalyst Deactivation History of Demonstrating Durability of Emission Systems Recreating Engine out Conditions Cost Effectively Catagen Performance Testing/Characterization of Catalysts Conclusion 3
Meeting the Challenge To Meet Emissions Standards Worldwide Requires effective after-treatment (Catalytic Converter Systems) with reductions of : 95% for US LEV 1 96% for Euro 4 98% for US ULEV 2 >99% for US SULEV Durability of Emissions Applied LEV & ULEV at 50,000 miles U.S. Tier2 = LEV2 and ULEV2 at 120,000 miles SULEV at 120,000 miles (PZEV at 150,000 miles) SULEV & PZEV are toughest worldwide 4
HC (g/mi) Emissions History 2.5 2.0 US 1979 1.5 Engine Out 2005 1.0 EU 1993 0.5 US 1991 0.0 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 Euro 3 NOx (g/mi) 5
HC (g/mi) A Closer Look 0.6 0.5 0.4 US 1991 0.3 Euro 3 0.2 Euro 4 ULEV-2 0.1 LEV-1 0.0 0.0 0.2 0.4 0.6 0.8 1.0 1.2 SULEV NOx (g/mi) 6
The Basics - TWC Equation 1.3 Basic Global Reactions in a TWC NO Re duction N Pt& Rh X 2 Other SlowHC Oxidation Pt& Pd xco 2 yh 2 O CO Oxidation PdPt& Rh CO 2 FastHC Oxidation Pt& Pd xco 2 yh 2 O Figure 3: Three-Way Catalytic Converter in Open Can With Matting 7
Fresh Catalyst Figure 4: Conceptual Model of Catalytic Sites on Washcoat Bonded to a Monolith Figure 5: SEM Micrograph of Fresh Catalyst 8
Catalyst Deactivation Factors Affecting Catalyst Deactivation: Temperature effects on catalyst Thermal Deactivation US-EPA Recognise this contributing 95% of total degradation Poisoning of Catalyst (Contaminants in Fuel) Fouling of Catalyst (Combustion Related Contaminants Soot/Oil) Structural breakdown of catalyst (Mechanical Shock) 9
Thermal Effects Figure 6: Conceptual - Phase Changes in Washcoat Thermal Effects Figure 7: SEM Micrograph Alpha Alumina, α-al2o3 10
Thermal Effects Figure 8: Conceptual -Thermal Sintering of Precious Metal Figure 9: TEM Micrograph of PM Sintering 11
Fouling of Catalyst Figure 10: Conceptual Fouling /Masking of Precious Metal Heavy Contaminants Unburnt Oil Etc 12
Catalyst Poisoning Trace Contaminants Found in Fuel Cause Alloying and Poisoning of Precious Metals: Phosphorous (P) Sulphur (S) Chlorine (Cl) Arsenic (As) Selenium (Se) Tellerium (Te) Sodium (Na) Calcium (Ca) Lead (Pb) Tin (Sn) Antimony (Sb) Mercury (Hg) Cadmium (Cd) 13
Fleet Data Equating Fleet Data to Demonstrate Catalyst Durability for Legislation Vehicle Fleet Histogram Data Catalyst Temperatures Equated to High Temperature Engine Test Cell Aging Typically 800-1100C USING US-EPA BAT EQUATION 14
Application of BAT Basic Integral Equation Where t h is the time at temperature T v This can be applied to any drive cycle or other test t I is then the temperature time integral characteristic of aging From this a new aging time t e can be calculated at reference temp T r This can also be used to match a specific bench ageing profile where Equivalent Bench Time For example 2500 hrs of FTP drive cycle on a PZEV vehicle matches to 80hrs of bench ageing at 800ºC 15
Snowmobile Emissions Phase Model year Phase-in Emission Maximum (percent) standards limits HC CO HC CO Phase 1 2006 50 100 275 Phase 1 2007 2009 100 100 275 Phase 2 2010 and 2011 100 75 275 Phase 3 2012 and later 100 see equation 150 400 From Regs Or more simply Total Total Emissions Emissions 1 HC 150 100 HC CO 150 400 CO 1 400 100 % 100 100 EPA Title 40 Part 1051: Control of Emissions from Recreational Engines and Vehicles EPA: 40 CFR Parts 60, 63, et al. Control of Emissions from Nonroad Spark-Ignition Engines and Equipment; Proposed Rule 2007 - Emissions Durability Proposal 16
The Problem The Issues: To Meet Ever Increasing Global Endurance Emissions Targets Catalysts need to be Constantly Improved Understanding of Deactivation Important to Assess And Improve Catalyst Formulations In House Endurance Testing Difficult and Costly On Road Catalyst Ageing Dependant heavily on driving traits Dynamometer Ageing Useful but Expensive! 17
The Problem From: Emissions and Health Unit Institute of Environment and Sustainability EC-JRC Ispra 18
Alternative Solutions Chamber Furnace Ageing: Thermal Ageing Very Difficult to Equate to Road Ageing No Flow of Gases Mostly carried out in air causes high degradation Low Cost Examples: QUB Chamber Furnace Ageing 19
Alternative Solutions Total Synthetic Gas Ageing: Typical Synthetic Gas Reactors Gas Exhausts to Vent Very Costly Examples: Published work shows Ford, GM, JM and Research Institutions have all experimented with this SAE 960795 20
Alternative Solutions FOCAS Burner Based Ageing: Spin Out Technology from SWRI Texas Commercially Available Cost Saving Benefits http://www.swri.org/4org/d03/engres/focas/aging/default.htm 21
Alternative Solutions Other Burner Examples FEV (Germany), Ford (US), and Schenck (Now Horiba) have all experimented with Burner Technology Schenck had offered it as a product in the past Queen s University, Belfast Experimented with Burners in Late 90 s Control Issues (MSc Degree) Thermal Control Issue Decided to Go Down another Research Route 22
Making economic and environmental sense of catalyst ageing 23
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Labcat Aging Cat 25
Volume Concentration (%) RAT Cycle Propane and Oxygen Concentrations 3 Oxygen Propane 2 1 0 0 20 40 60 80 100 120 Time for Two Cycles (Seconds) 26
AFR AFR RAT Cycle Air Fuel Ratio at At Catalyst Inlet 1.2 1 0.8 0.6 0.4 0.2 0 LEAN RICH 0 20 40 60 80 100 120 Time for Two Cycles (Seconds) 27
Temperature C Aging Results 1000 RAT Aging Example B 950 900 850 Bed Inlet Outlet 800 750 700 0 50 100 150 200 250 300 350 400 450 500 Time s 28
Temperature C Aging Results 1000 Simulating Fuel Cut Portion of ZDAKW Cycle 980 960 940 920 900 880 Bed Inlet Outlet 860 840 820 800 0 50 100 150 200 250 300 350 400 450 500 Time s 29
AFR Temperature C Aging Results 18 Fuel Cut AFR ZDAKW Cycle 17 16 15 Outlet Inlet 14 13 12 0 50 100 150 200 250 300 350 400 450 500 Time S 30
Catalyst Manifold Temps Thermal Shock 900 850 Catalyst Thermal Shock Test Bed Temp 1 Inlet Temp 1 Bed Temp 2 Inlet Temp 2 Outlet Temp 800 750 700 650 600 Catalyst Inlet Ramp Rate = 170 o C/Second 550 500 450 400 0 20 40 60 80 100 120 140 160 180 200 Time (s) 31
Performance Testing 32
Conversion (%) Sweep Test Sample 100 Conversion - Lambda - Sample 6 90 80 70 60 50 40 30 20 10 Conv % CO Conv % HC Conv % NO 0 0.90 0.95 1.00 1.05 1.10 1.15 1.20 Lambda 33
Conversion (%) CO Lightoff Sample 100 CO Conversion - Cat In - Sample 6 90 80 70 60 50 40 CO LIghtoff @ 221 C 30 20 Conv % CO 10 Conv % NO 0 150.00 170.00 190.00 210.00 230.00 250.00 270.00 Cat Inlet Temp (C) 34
Conversion (%) C3H8 Lightoff Sample 100 C3H8 Conversion - Cat In - Sample 4 90 80 70 60 50 40 HC Lightoff @ 439 C 30 20 10 Conv % HC 0 150.00 200.00 250.00 300.00 350.00 400.00 450.00 500.00 550.00 600.00 Cat Inlet Temp (C) 35
Lambda OSC Test Sample 1.40 Lambda Comparison 1.30 1.20 1.10 1.00 0.90 0.80 0 100 200 300 400 500 600 700 Mexa 7170 Lambda Time (s) Labcat Lambda In Labcat Lambda Out 36
Lambda OSC Test Sample 1.30 Lambda Comparison 1.25 1.20 1.15 1.10 1.05 1.00 0.95 0.90 0 100 200 300 400 500 600 700 800 900 1000 Mexa 7170 Lambda Time (s) Labcat Lambda In Labcat Lambda Out 37
PRODUCT RANGE MAXCAT 200g/sec TESTCAT 50g/sec LABCAT 20g/sec Flow 38
MAXCAT EXAMPLE Removes the need for Gasoline & Energy Efficient! ENERGY Coolant Heat Useful Work Exhaust Heat Gasoline Energy 95% Electrical 5% Propane Catagen systems require 80% less energy = Cost Savings! Typical Reduction in Operating Cost 70-85% 39
OTHER BENIFITS No Need for Engine Test Bed Facilities Laboratory Environment (Cost) Estimated 1 Technician to Operate 3 Catagen Machines Personnel Reduction Remote monitoring facilities/ipad Applications/Remote Alarms SMS/Email Aging and Performance Carried out on Same System Highly Repeatable Tests, Easy Experimentation & Analysis 98% CO 2 Reduction at Source Safety TUV Certification, CE Marking, NFPA 79 40
SUMMARY Catalyst Durability a Key Component Global Air Quality Legislation: Faster Light-off Requirements Lower Emissions Levels Longer Durability Requirements Expanding into New Geographical Territories Expanding into Other Engine Applications (Beyond Auto) In Catagen Developed a tool to aid the industry 41
Thanks For Listening And Good Luck to All the Teams Participating in SAE 2011 42