Eugène Jules Houdry (Domont, France, April 18, 1892 – Upper Darby Township, Pennsylvania, July 18, 1962)[1] was a mechanical engineer who graduated from École Nationale Supérieure d'Arts et Métiers in 1911.

[6] [4] Houdry studied mechanical engineering at the École des arts et métiers in the Paris suburb of Chalons-sur-Marne.

Recognizing that the key to better performance of automobiles and airplanes was the improvement of fuels, he became interested in the catalytic processes used to convert coal and lignite to gasoline.

[15][3][4][6] In 1922, Houdry visited the United States, where he saw the Indianapolis 500, and toured a Ford Motor plant in Detroit, Michigan.

In Italy, a French pharmacist named E. A. Prudhomme was the principal scientist of a group experimenting with promising techniques for water-gas synthesis.

[19] "During the lignite-to-gasoline process, the solid lignite was initially broken down by heat to produce viscous hydrocarbon oil and tars, then the oil was further converted by an added catalyst to produce lower-boiling hydrocarbons similar to the gasoline fraction derived from petroleum.

[15][13][3] During World War II, Houdry strongly opposed the government of Vichy France under Marshal Philippe Pétain and its collaboration with Germany.

As president of the U.S. chapter of France Forever (where his brother-in-law, Pierre Quilleret,[27] was also one of the founders), Houdry vocally and publicly criticized Petain, stating that he did not speak for the French people.

[28] Houdry supported General Charles de Gaulle, leader of the provisional French government in exile.

[5][2] Both of Houdry's sons, Jacques and Pierre, served in World War II as part of the United States Army.

[18] Houdry originally focused on using lignite (brown coal) as a feedstock, but switched to using heavy liquid tars.

[11] The process was further developed by two MIT engineers, Warren K. Lewis and Edwin R. Gilliland, under contract to Standard Oil of New Jersey, now ExxonMobil.

[22][31] Houdry also invented a catalytic process to produce butadiene from butane gas, which was formed during crude oil production.

He built a generic catalytic converter capable of reducing carbon monoxide and unburned hydrocarbons from automobile exhausts.

[2][13][32] Catalytic converters eventually became standard equipment in American cars, following passage of the Clean Air Act, introduced by Edmund S. Muskie in 1970.

[33] Houdry's contributions to catalytic technology were recognized by numerous awards, including the Potts Medal of the Franklin Institute in 1948,[34][35] the Perkin Medal of the Society of Chemical Industry (American Section) in 1959,[30] the E. V. Murphree Award in Industrial and Engineering Chemistry of the American Chemical Society in 1962,[36] and posthumous election to the National Inventors Hall of Fame in 1990.