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E. Do pelleted catalyst produce particulate matter due to attrition and

do they emit carcinogenic matter?

ANSWER: In four (4) 50,000 mile tests of pelleted catalyst, which have previously been reported to the EPA, we found that an average loss of the Noble Metal was 0.6 micro-grams per mile. In all of these tests the weight of the catalyst after the test was more than the weight of catalyst going into the test. From this it is apparent that the emission of particulate matter due to attrition is practically non-existent. It is interesting to note that lead emissions from a vehicle using ordinary leaded fuel at 3 grams per gallon emit 50,000 times the weight of lead as we would expect converters to emit platinum. Even when the lead level in the fuel is reduced to .05 grams per gallon, lead emissions will still be 500 times greater than platinum emissions. Both lead metal and lead salts are known to have toxic effects whereas platinum metal is not known to have toxic effects.

With regard to the second part of the question, catalytic converters have been found to be 95% effective in removing polynuclear aromatic hydrocarbon (PNAH) tars from automobile exhausts. Typical automobile exhaust emits about ten milligrams of these tars in one hour. This compares to eighteen milligrams contained in the smoke from one cigarette. After passing through a catalytic converter, the same amount of exhaust would contain only 0.5 milligrams of tar. This means that all of the exhaust from a vehicle equipped with a catalytic converter would

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have to be inhaled for 36 hours before exposing the body to the

same amount of tar contained in one cigarette.

F. What is the effectiveness of a catalytic converter with regard to reduction

of emissions and odor from a diesel engine?

ANSWER: Our tests have shown that a pelleted catalyst system will reduce

diesel engine emissions of hydrocarbons and carbon monoxide about 70%. With regard to odor emissions, tests have indicated that the catalyst is very effective in reducing odors to a level where they are non-existent or very faint. Supporting data for the above statements are contained in Exhibits A and B attached hereto.

What is the energy loss in producing sufficient quantities of lead-free fuel to run catalyst supplied vehicles?

ANSWER: Catalytic systems have been proven to increase the performance

and efficiency of vehicles which previously had been tuned for maximum pollution control. This increase in performance and gas mileage is due to several factors among which are the modifications of the air/fuel mixture and spark advance. Attached to this statement as Exhibit C is a statement prepared by Dr. Vlalimir Haensel, Vice President Science and Technology and Mr. Melvin J. Sterba, Assistant to the Vice President of Development Process Division, of Universal Oil Products Company. This statement focuses attention to the energy problem with regard to emission control.

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H.

Does UOP's pelleted alumina base catalyst shrink?

ANSWER: About two years ago our platinum bearing catalyst (PZ-195) was exhibiting a fair amount of shrinkage and subsequent attrition.

A study was made to see at what temperature this occurred and what could be done about it. Exhibit D attached hereto shows the data for that catalyst and shows that at 1600° F bed temperatures there was a 25% catalyst loss with only 51 cycles of operation. A new catalyst was developed (PZ-216) and at tests run at the same temperature it ran twice as long with no catalyst loss. The exhibit also shows that the stabilized catalyst at 1900° F showed only a 3% loss as compared to the previous 25%.

The stabilization technique used for this catalyst (PZ-216) was
one that was brought about by the incorporation of a compound in
the catalyst which prevents the shift from gamma alumina to alpha.
This is the shift in alumina structure which brings about shrinkage,
smaller surface area and less strength.

The above cited data were collated on a single cylinder engine.
The credibility of that data was improved by running durability
tests on the stabilized (PZ-216) and unstabilized (PZ-195) catalyst
in a 1971 vehicle to determine catalyst loss. Exhibit E sets
forth these tests and verifies the single cylinder data showing a
strong improvement in reducing catalyst loss due to shrinkage.

W. R. Price, Jr.
July 10, 1973

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If combustion of the air-fuel mixture in the cylinder were complete, the

products of combustion would be primarily carbon dioxide and

water

vapor,

with

oxygen and nitrogen remaining from the ingested air. The diesel engine does not produce complete combustion. Because of this, the engine becomes a source of air pollution by emitting exhaust gas products such as carbon monoxide, unburned hydrocarbons, hydrogen and oxygenates. The carbon monoxide concentration varies with air-fuel ratio; values from 0.05% at lean air-fuel ratios to 0.5% at stoichiometric have been experienced. Hydrocarbon concentrations do not depend on air-fuel ratio and will vary from 50 to 200 ppm depending on such factors as cylinder surface to volume ratio, combustion chamber deposits and mode of operation. Although the concentration of the pollutants is low, the mass emissions from diesel engines can easily be above the Federal standards of 1970 for passenger cars because of the higher volume of exhaust gas emitted per engine.

Past methods of treatment for the pollutants emitted are filtration, absorption on a material such as activated charcoal; the use of masking agents, or methods to chemically change these compounds such that they are converted to less noxious compounds. Physical removal by filtration or adsorption has the disadvantage of limited capacity and frequent servicing. Masking the odor is no solution. Exhaust

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