Real World Evidence of mmt® Compatibility with
Modern Vehicle Technology

Vehicle sales in China have developed during the past decade such that China is now the larget single market for new vehicle sales in the world. With this rapid sales growth, roughly 70% of China’s total passenger car parc is now comprised of vehicles 5 years old or less. This represents one of the highest proportions of advanced vehicle technology of any market in the world.

Nearly 80% of China’s vehicles are gasoline powered. The compilation of studies below shows that advanced vehicle technologies continue to produce low emissions and protect the environment when using gasoline produced to Chinese fuel standards, which includes the use of the octane enhancer, mmt®.

Influence of Gasoline Fuel with mmt® on Catalyst Performance

• Exploratory investigation by the Laboratory of Automotive Safety and Energy at Tsinghua University into the interaction of combustion products from mmt®-containing gasoline with high cell density (600 cpsi) catalysts during severe operating conditions, typical of those used for accelerated catalyst aging during the vehicle durability demonstration process
• Use of high temperature, steady-state aging cycles is not representative of deposition phenomena that occurs during real-world operating conditions
• Results from additional catalyst characterization experiments showed that there was no substantial correlation between catalyst conversion efficiency performance and the presence of manganese oxide deposits on the catalyst face

(Source: Experimental Study of Influence of Gasoline Fuel with MMT on Aging Performance of Three-way Catalyst, 3rd Annual Conference of Oil Products and Clean Fuels Branch of Chinese Society for Internal Combustion Engines, May 2011)

Study of China Automotive Technology and Research Center (CATARC)

• Investigation into the durability of modern vehicle emission control systems in China during real-world use
• Results support the conclusion that emission systems deterioration is caused by thermal catalyst degradation and engine oil poisoning related to vehicle use
• Emission system deterioration was not associated with catalyst manganese concentration
• Vehicles, including high-mileage vehicles that fail to meet the in-use emission standard do so because of vehicle use that causes thermal degradation and engine-oil derived poisoning of catalyst systems. These failures are not related to fuel quality

(Source: 16th Annual Fuels & Lubes Asia Conference, March 4-5, 2010, Singapore)

Ministry of Environmental Protection (Previously known as SEPA)

• Comprehensive field trial with Euro IV vehicles conducted by the State Environment Protection Agency (now Ministry of Environmental Protection)
• Final report confirms compatibility of mmt® at 18mgMn/l to Euro IV durability and emission requirements

(Source: Yan, Z., et al, Research of Environmental Sciences Vol. 19 No. 5, 2006)

The Interaction of mmt® Combustion Products with the
Exhaust Catalyst Face

SAE 2007-01-1078

Overview:

Afton Chemical technology helps fuels burn cleaner, engines run smoother and machines last longer. We are committed to ensuring our products are environmentally safe and fully compatible with consumer expectations. In SAE paper 2007-01-1078, Afton Chemical presents results from testing the fundamental mechanisms that govern interactions between engine combustion products and exhaust catalysts. These studies address the impact of exhaust temperature, engine transients, use of HiTEC 3000 Series of mmt® fuel additive and catalyst cell density on the accumulation of combustion products on the catalyst.

These studies provide the following significant information:

• The experimental test procedures used nearly 30 years ago that explained catalyst plugging mechanisms can be used to the same effect in modern vehicles fitted with close coupled high cell density catalysts;
• When the experimental test procedure includes operating conditions associated with normal consumer driving, particle detachment forces are introduced and catalyst plugging is not measured; 
• Real world evidence supports mmt® compatibility with modern vehicle technology.

Conclusions:

The experimental test procedures used nearly 30 years ago that explained catalyst plugging mechanisms can be used to the same effect in modern vehicles fitted with close coupled high cell density catalysts

• In a 1978 SAE paper, Furey and Summers demonstrated that by eliminating the normal variability vehicles and engines experience in the real world, catalysts can plug.
• Under these experimental conditions, the rate of particle adhesion to the catalyst is a function of exhaust temperature
• A recent paper, SAE 2007-01-1070, Honda researchers showed that under the same controlled conditions, the rate of particle adhesion to the catalyst is also a function of catalyst cell density

When the experimental test procedure includes conditions that exist under actual driving conditions, particle detachment forces are introduced and catalyst plugging is not measured

• Afton’s study was designed to specifically include particle detachment forces. A simple periodic transient, of the type observed when a vehicle slows down, during otherwise steady state engine operation resulted in significant detachment forces.
• Increased pressure drop is not measured when particle “detachment” or “release” mechanisms such as those associated with an exhaust temperature transient are incorporated.
• The introduction of detachment forces to prevent increased catalyst pressure drop in lower cell density catalysts was shown to have the identical effect on high cell density catalysts
• During typical consumer vehicle use, additional particle detachment forces are encountered that were not considered in this series of experiments and would be expected to further increase particle removal rates. 

For copies of the above referenced papers, please Contact us.