CATALYST ASSESSMENT
![Slide 1](http://www.dcl-europe.com/images/catalyst-assessment/slide1.jpg)
DCL carefully considers all mechanisms involved in catalyst deterioration, to ensure the long-term performance of target emissions. DCL maintains a large database of model gas, test cell, and in-field catalyst aging data.
Ideal Surface
- Good adhesion
- Well-dispersed particles
- Similar thermal expansion coefficients of substrate and washcoat
Chemical Deterioration
![Sulphur poisoning (reversible, greater than 600<sup>o</sup>C / 1110<sup>o</sup>F caused by ZDDP (zinc dialkyl dithio phosphate) Lube oil poisoning - Phosphorus poisoning (irreversible)](http://www.dcl-europe.com/images/catalyst-assessment/t/chemical-deterioration.jpg)
- Sulphur poisoning reversible at greater than 600oC / 1110oF, caused by ZDDP (zinc dialkyl dithio phosphate)
- Lube oil poisoning by phosphorus additives (irreversible)
- Poisoning; irreversible adsorption or reaction on/with the surface
- Inhibition; competitive reversible
- adsorption of the poison precursors
Thermal Deterioration
- Sintering (re-dispersion)
- Alloying
- Support changes
- Noble metal-base metal interactions
Fouling
Mechanical Deterioration