User talk:Hist406-11Hdoukmaj/catalyticconverter

Michel Frenkel, a French chemist, provided the first account of the catalytic converter in 1909. Frenkels’ invention was a device that used china clay with platinum as the active catalytic material. Krenkel’s version had exhaust gasses being blown by a fan into the device. At this time, the catalytic converter really had no use and was nothing besides an idea. The next report of the catalytic converter was in the 1920’s by a German inventor (unknown). This device used a collection of wires and beads that were coated with platinum. It failed because the catalyst would burn up and fall off within seconds. (2) Eugene Houdry, considered as a crucial contributor in the 1920’s and 30’s had started his innovation of the catalytic. (3) The first company that focused on the catalytic converter was formed in 1948 by Houdry called “Oxy-catalyst.” (4) In 1959, Houdry had developed the first catalytic converter onto the exhaust system of an automobile. (5) His system contained a rectangular box which had 71 porcelain rods placed in rows and staggered. The rods were coated with aluminum and platinum which is what acted as the active catalyst. It functioned by having exhaust gasses from the combustion enter into the can, and pass through the rows and rods that were within it. (6) Before the catalytic converter was commercialized for the automobile, it was innovated for industrial processes. (7) In the 1960’s the catalytic converter was being developed for forklifts’ need to decrease emissions in warehouses, by Carl Keith of Engelhard Industries. (8) The porcelain rods of Houdry’s device were exchanged with zirconia-mullite blend. (9) The honeycomb design, covered by a layer of high surface area aluminum and platinum was also implemented by Carl Keith. The honeycomb was placed in a cylinder and showed successful results of reducing the carbon monoxide in the exhaust. (10) The catalytic converter lacked real interest and demand and was not close to being commercialized, until the passing of laws requiring reduced emissions. (11)

U.S Clean Air Act 1970

The passing of the Clean Air Act (CAA) by Richard Nixon, (12) accelerated the rapidity of innovation for the catalytic converter. (13) The CAA of 1970 demanded automobiles reduce 90 percent of emissions of hydrocarbons and carbon monoxide in exhaust gasses of cars of 1975. (14) All automobile companies were forced to comply or face a possible shut down. This lead to widespread and frantic research of the catalytic converter because the government showed it was no longer taking emissions lightly. ( 15)

Innovations of the Catalytic Converter

The pelletized catalytic converter was invented by GM automotive company. The pellet system was a container that housed many pellets which served as the catalyst to the exhaust gasses passing through. (16) The pellet system was deemed unsuccessful at the time because of the high amount of backpressure it had exerted on the engine, and because of the thermal expansion between the pellets and the container it was housed in. (17, 18) The innovation of extrusion by Rodney Bagley, an engineer at Corning Glass Works was key to our modern catalytic converter. (19) He wanted to introduce honeycombs with the method of extrusion which made the honeycomb out of a single cellular piece, this was a major breakthrough. This method is what the current catalytic converter of today is now using. Research was done at Corning to try to use cheaper metals that were not as expensive as platinum and palladium. (20) The cheaper materials failed the tests because of their inability to remove sulfur from the exhaust gasses. (21, 22) This led Corning to stick with more precious metals even though it would prove to be a bit more costly. The amount of platinum in the composition of the honeycombs was reduced to only being 0.15 percent of the material. With innovative ways, the less amount of platinum was spread more strategically throughout the honeycomb in order to achieve the same results. (23) The next big innovation to the development of the catalytic converter was the use of cordierite to withstand the high temperatures and prevent melting. It also helped improve the thermal shock resistance. This step finally solved the problems of melting catalytic converters. (24)

Commercialization of the catalytic converter

The first car that passed the 1975 standards of emissions was the Chrysler Avenger. The catalytic converter used on the Chrysler was equipped with rhodium promoted platinum oxidation catalyst that was developed by Johnson Matthey. (25) This early version of the catalytic converter, used an air pump in order to better complete the combustion of o2. This early system of the catalytic converter was called the oxidation catalyst concept. This concept successfully met the standards of controlling CO and HC of the Clean Air Act. (26) These two stipulations were the main things that the government wanted to focus on with the Clean Air act of 1975, but after these two were met, stricter rules were passed on emissions. The EPA then added on to their Clean Air Act of 1975 by demanding a reduction in NO and NO2 gasses along with the CO and HC. (27) The Engelhard company was able to accomplish this difficult feat by adding another catalytic converter to the exhaust system which strictly dealt with reducing NO and NO2. The first catalytic converter was to reduce NO2 in the exhaust, while the second catalytic converter served to reduce CO and HC. This system came to be known as the Dual Catalytic Converter Concept. (28) The dual catalytic converter system satisfied the requirements of the extended Clean Air Act, but it did not help with costs of manufacturing. The dual converter system was deemed expensive and costly to manufacture. (29) Further research continued to meet the standards of the EPA, at the same time reducing costs. John Mooney had tested with different materials and different ways to try to get all aspects of filtering the exhaust gases into one catalytic converter. (30) Thus, the three way catalytic converter was developed which treats all three components required by the EPA. (CO, HC, and NOx) The three way system is still used today, and always ever improving. (31)