Houdry, Eugène Jules

views updated


(b. Domont, France, 18 April, 1892; d. Upper Darby, Pennsylvania, 18 July 1962),

chemical engineering, catalytic cracking of petroleum, catalysis.

In the 1930s, Houdry became a successful inventor in the field of oil refining, an industry dominated by large firms with their own research laboratories. Houdry pioneered in the use of catalysts to “crack” the large hydrocarbon molecules in petroleum into smaller ones that could be used in gasoline. Not only did Houdry’s process increase the quantity of gasoline, but in addition its quality was superior to all existing gasolines. By 1942, fourteen Houdry units were operating to provide 100-octane aviation fuel for the Allied war effort in World War II. In many of its aspects, Houdry’s approach to research resembled that of Thomas Edison. His major area of concentration, catalysts—he became known as Mr. Catalysis—was a field that lacked useful scientific theory to guide research. Therefore, his approach was largely empirical, involving large numbers of experiments. Like Edison, Houdry combined intense labor, often going for days without sleep, with his experience and intuition to develop catalysts and processes that employed them. He surrounded himself with outstanding assistants whom he exhorted to maintain their focus on the goal and to overcome apparent roadblocks. As one longtime associate put it, “Houdry had one remarkable characteristic, and it was not inventiveness, it was the courage to make a total commitment to his convictions” (Mills, 1986, p. 75). In a forty-year research career, he obtained more than one hundred patents, including one for an automobile catalytic converter shortly before his death.

Childhood and Education . Houdry was born in the Paris suburb of Domont, France, on 18 April 1892, the only son of Jules Houdry, owner of a successful structural steel business, and Émilie Thias Jule Lemaire. To prepare himself to join his father’s firm, he studied mechanical engineering at the École des arts et métiers (School of arts and engineering) at Châlons-sur-Marne. He was a halfback and captain of the soccer team that won the French national championship in 1910. A year later he graduated first in his class and went to work as an engineer in his father’s plant. With the outbreak of World War I three years later, Houdry joined the French army as a lieutenant in the field artillery but was later transferred into the new secret tank corps. He took part in the first battle that used tanks as an assault weapon. At the battle of Juvincourt in 1917, he was wounded and awarded the Croix de Guerre for having organized the repair of disabled vehicles under heavy fire.

After rejoining the family business after the war, Houdry became increasingly interested in automobiles and served on the board of several automotive companies. His association with one parts manufacturer brought him into contact with engineers who were attempting to improve the performance of automobile engines. One limiting factor was engine knock, a phenomenon he had personally experienced while driving his Bugatti. In 1922 he attended the Indianapolis 500 and toured the Ford assembly plant in Detroit. Upon his return to France, he married Geneviève Marie Quilleret with whom he would have two children.

Petroleum from Coal . In 1922 Houdry combined his passion for automobiles and his French patriotism by becoming involved in developing processes for making gasoline from coal, an abundant resource in petroleum poor France. Houdry learned that in Nice, Eugene A. Prudhomme was generating carbon monoxide and hydrogen from lignite and then using a series of catalyzed and uncatalyzed reactions to create gasoline. After an initial visit to Prudhomme’s laboratory, Houdry invested in the enterprise and organized a group of experts to investigate the process. In spite of its many shortcomings, especially a low yield of gasoline and a general lack of understanding of the chemical reactions that were occurring, Houdry decided to form a company to continue the development of the process. He began to study the chemistry of hydrocarbons and set up a laboratory at Beauchamp, near Paris. Within a few months Houdry, assisted by several engineers, built a larger unit that, however, refused to yield any gasoline. Word soon came of similar results obtained by an Italian group. At this point Houdry made a fundamental change to the process: He distilled the lignite to create tars that were upgraded to gasoline using the same hydrotreating steps employed in the Prudhomme process. After months of intense effort, gasoline was obtained. Particularly encouraging was its quality, because at this point in automotive history engine knock was becoming a major problem that limited engine performance.

In 1924 Houdry incorporated what would become the Houdry Process Company of France (Société Anonyme Française pour la Fabrication d’Essences et Pétroles). Over the next three years he continued to improve his process, although much of his time was spent as a promoter rather than as an experimenter. In 1927 it was officially recognized (i.e., sanctioned) by the French government, which directed that a larger pilot plant be constructed (though no subsidies were provided). This plant, which processed sixty tons of lignite per day, started up in June 1929; the gasoline output, however, was 30 percent lower than expected. Although the plant worked, and produced high quality gasoline, the cost was high and the French government decided not to continue the expensive development effort. After a year of operation the plant shut down. By this time, though, Houdry’s efforts had shifted to a new area—catalytic cracking of heavy petroleum fractions.

Catalytic Cracking . As the number of automobiles increased rapidly in the 1920s, there was widespread concern about the future supply of gasoline. One response to this expected crisis was the development of processes to make gasoline from coal, especially in countries such as Great Britain, France, and Germany that did not have major domestic sources of petroleum. Another approach was to get more gasoline out of a barrel of crude oil. Crude oil is a mixture of hydrocarbon molecules containing from five to forty carbon atoms. Gasoline consists of relatively volatile or “light” hydrocarbons containing from five to twelve carbon atoms. The gasoline fraction accounts for only about 20 percent of crude oil. More gasoline could be produced if some way could be found to break up, or crack, the larger hydrocarbon molecules. Particularly amenable to cracking were the thirteen to twenty-three carbon atom-range molecules, constituting gas oil that accounted for 40 percent of crude oil. In 1913 William Burton, at Standard Oil of Indiana, developed a process that cracked nearly half of gas oil into gasoline using high temperature and high pressure. During the 1920s so-called thermal cracking had spread throughout the U.S. refining industry.

While he was working on lignite tars, Houdry realized that his process might also work on heavy petroleum fractions. His research focused on finding an efficient catalyst, which required careful experiment design to give meaningful comparisons among catalytic materials. At the time the conventional catalyst was a metal supported by porous materials such as kaolin, fuller’s earth, and clays. He had learned earlier, when working with lignite tars, that a major problem with catalytic cracking was that a carbon or coke layer quickly coated the catalyst surface, thereby greatly reducing its effectiveness. What Houdry was looking for was an effective catalyst that would not be destroyed by burning off the coke, a process he called regeneration. After many unsatisfactory experiments with metals, he decided to try the support material without the metal. The results were encouraging and led to a systematic canvassing of claylike materials. In April 1927 he tried an activated clay, used as an adsorbent to purify lubricating oils, which worked well. To test this gasoline cracked from a heavy crude, he tried it out in his Bugatti racer. When his speedometer hit 90 miles (145 km) per hour with the engine still running smoothly, he realized that he had succeeded in turning low-grade crude oil into high-quality gasoline. Just how good the gasoline was could not be determined for a few more years, until the modern octane-rating system was developed.

Houdry realized that commercial development would require large sums of money and specialized engineering expertise, so he sought to interest oil companies in his process. He publicized his findings and as early as November 1928 began to demonstrate it for companies such as the Anglo-Iranian Oil Company (now British Petroleum), Royal Dutch Shell, and Standard Oil of New Jersey. However, these companies did not show much interest in the process because many new and difficult engineering problems would have to be solved to make a commercial-scale facility, and the companies were more interested in a competing technology, hydrogenation, which had been developed by the giant German chemical company I. G. Farben.

In 1930 Houdry made contact with the Paris office of Vacuum Oil Company and arranged for the company’s European representative, Harold F. Sheets, to visit his laboratory. After seeing Houdry’s operation and examining his portfolio of more than fifty patents, Sheets proposed that Vacuum construct a pilot plant if Houdry would bring his apparatus to the United States and operate it continuously for fifteen days. In the fall of 1930, Houdry came to Vacuum’s refinery on the Delaware River in Paulsboro, New Jersey, and successfully demonstrated his process. Analysis of the gasoline showed that it was of high quality and had good stability. By May 1931 Vacuum had constructed a sixty-barrel-per-day pilot plant to crack gas oil. About this time the Houdry Process Corporation was organized, with Vacuum having one-third interest and Houdry and his associates the other two-thirds. Soon afterwards, though, the project lost considerable momentum, a victim of the deepening economic depression, and Vacuum’s merger with Socony Oil Company. In the spring of 1933, Socony-Vacuum decided to discontinue its support of the project.

The Houdry Process . Houdry next looked across the Delaware River to the Sun Oil Company, whose refinery was located at Marcus Hook, Pennsylvania. He was able to convince Arthur E. Pew Jr. (son of the founder and brother of the president) and chief engineer Clarence H. Thayer to take half of Houdry’s interest, making Vacuum, Houdry, and Sun equal partners. Sun had been a lubricating oil company that moved into gasoline during the automobile boom of the 1920s. Sun produced a high quality gasoline that did not need tetraethyllead (TEL) to boost its anti-knock capability. TEL had been commercialized in the late 1920s by General Motors and Standard Oil of New Jersey. Sun was looking for ways to stay ahead in the octane race without having to pay royalties to these corporate giants.

Although the Houdry process produced high quality gasoline, the process was complex and cumbersome. The main problem was the buildup of coke on the catalyst that eventually stopped it from functioning. Houdry’s solution to this problem was to burn the coke off the catalyst with air. This required that the process include three reactors, only one of which would be making gasoline. A second would be vacuum purging residual oil vapors from the reactor, which was necessary to avoid an explosion during the third step, burning coke off the catalyst. In April 1936 a two-thousand-barrel-per-day semi-commercial unit was started up at Paulsboro. A year later a much larger, fifteen-thousand-barrel-per-day unit, began operation at Marcus Hook. Size was not the only difference between the plants: Whereas the first plant cracked the relatively light gas oil, the later one attacked very heavy crude oil, a cheaper but more difficult to process feedstock. Also, Sun had made some major modifications to the process. Studies of the cracking process revealed that coke built up so rapidly on the catalyst that after fifteen minutes of operation, little additional gasoline was produced. At this time the plants had been running on cycles that were hours long. Switching to very short cycles created a number of challenging engineering problems. First, they required automated process control, a relatively new technology in the 1930s, to switch the functions of the three reactors. To burn off coke quickly, Sun engineers had to use a turbo-compressor to supply the large volume of air required. Removing the tremendous amount of heat generated during regeneration led to the substitution of molten salt heat transfer agents for water.

While Sun engineers worked out the process, Houdry spent much of his time working on improving the catalyst that had to meet activity, selectivity, and life specifications and needed to be mechanically strong and survive under process conditions. To supply catalyst materials, Houdry relied on the Filtrol Corporation, which used a wide variety of clays for the purification of oils, fats, and waxes. After extensive experimentation, a bentonite-type clay consisting of silica and alumina was chosen. In 1940 Houdry shifted over to a synthetic silica-alumina catalyst that eliminated the variability inherent in natural materials.

Commercial Success . Arthur Pew Jr. announced the commercialization of the Houdry process at an American Petroleum Institute meeting in November 1938. Although the Houdry process generated about as much gasoline as did existing thermal cracking units, the catalytic product had a octane number of 88 compared to 72 for the noncatalytic product. In addition, the Houdry process created higher value by-products that could be burned as fuel oil. In the next few years, Socony-Vacuum and Sun, along with a few other oil companies, made major investments in Houdry units. By 1944, twenty-four units had been built, accounting for 10 percent of the nation’s cracking capacity. No new fixed-bed Houdry units were built after that date as catalytic cracking shifted to continuous processes that moved the catalyst through the reactor with the petroleum gases. After exiting the reactor, the catalyst was separated from the gases and sent to a separate regeneration reactor. Early-moving catalyst processes, including one developed by the Houdry organization, used mechanical means to convey the catalyst, but the eventually dominant process, developed by Warren K. Lewis and his co-workers at the Massachusetts Institute of Technology in Cambridge, Massachusetts, and Standard Oil of New Jersey was based on fluidized bed technology. In this process, the catalyst particles are fluidized by the petroleum gases and move through the reactor either upward with the gases or downward by gravity.

The Houdry process, though short-lived, played a critical role in contributing high-octane gasoline that could serve as the base for 100-octane aviation fuel. During World War II this fuel helped give the Allies the edge in the air because the Germans could not get their octane number above 90. During the war’s first two years, Houdry units produced 90 percent of the catalytically cracked gasoline.

During the 1930s the Germans tried to get access to Houdry’s process, but concerns over Nazi intentions led Houdry to break off negotiations in 1937. Two years later he visited France to advise the government on gasoline issues but could not get much support for his process. After the fall of France in June 1940, Houdry helped to organize the committee France Forever to support the Free French in their efforts to defeat the Nazis. He later became president of that organization and in 1943 had to defend it from charges that it was committed to supporting Charles de Gaulle as the leader of postwar France. In 1942 Houdry became an American citizen.

Butadiene and Catalytic Theory . Eugene Houdry continued to work on the improvement of his process until 1941, when he shifted over to working on catalytic methods to make butadiene, one of the two chemicals needed to produce synthetic rubber—Japanese expansion into Southeast Asia late that year cut off the United States from is sole source of natural rubber. Houdry developed a catalyst that would convert a widely available refinery byproduct, butane, into butadiene in one reaction step. The process was similar in design to the original Houdry process, requiring three reactors simultaneously reacting, purging, and regenerating. Two rather small plants used this process during World War II, but it did not become a major process for butadiene manufacture.

Between 1944 and 1948 Houdry, while president of the Houdry Process Corporation, directed special research and development projects primarily for Sun. In 1948 he left the active management of his company and returned to independent investigation, using a stable behind his home in Ardmore, Pennsylvania, as his laboratory. Houdry had developed some general ideas about catalysis that served as the basis for his research. He asserted that catalysis was the fundamental mechanism of life, referring to humans as catalytic machines. He thought that industrial catalysts could be improved by studying enzymes and that industrial catalytic concepts could be applied to medicine. As an example of the latter, he speculated that cancer was caused by catalyst malfunction in cells and that a cure might come from either regenerating or replacing cellular catalysts. Another, more specific, project was using catalysts to promote flameless combustion in applications from extracting heat from waste gases to flameless cooking devices. He organized a new company, Oxy-Catalyst, in 1950 to develop applications of oxidizing catalysts. Several of his ideas coalesced into Houdry’s development of an automobile catalytic converter in the 1950s.

In the late 1940s, air pollution in cities such as Los Angeles was becoming worse and scientists connected it with smog caused in part by automobile emissions. At the same time the incidence of lung cancer was rising. Houdry became convinced that the two were causally linked. He pointed out that since 1915 the amount of gasoline burned in the United States had increased twenty-five times, exactly the multiple of lung cancer cases. Cigarette consumption, another suspected cause, had only increased three times over the same time span. Publicly connecting automobile exhaust with lung cancer must not have made him very popular with the oil and automobile companies. In the early 1950s he developed a catalytic converter that consisted of porcelain rods coated with a film of alumina and platinum. The major challenges he faced were those that would confront future designers of catalytic converters. One was that the devices had to operate effectively over a wide range of operating conditions, from starting on cold days to rapid acceleration at high temperatures. Another big problem was the poisoning of the catalyst by the lead in the gasoline. Houdry never completely solved these problems, but he did put his converters on forklift trucks that operated indoors and on unleaded gasoline.

In the postwar decades, numerous catalyst innovations revolutionized the chemical processing industries, but most of these developments came from well-funded laboratories staffed with PhD scientists and engineers. In recognition of his pioneering efforts in the field, Houdry was awarded the Howard N. Potts Medal of the Franklin Institute in 1948, the Perkin Medal of the Society of Chemical Industry in 1959, and the Industrial Engineering Award of the American Chemical Society in 1962. Posthumously—he died after a short illness on July 18, 1962—he was inducted into the National Inventors Hall of Fame in 1990.


There are materials relating to Houdry and his process in the Sun Oil Company papers (accession 1317) at the Hagley Museum and Library, Wilmington, Delaware. There are two other small collections of Houdry materials: the Eugene Jules Houdry Collection, 1938–1996, at the Chemical Heritage Foundation in Philadelphia and the papers of Eugene Jules Houdry, 1931–1980, in the Library of Congress manuscript collection.


With Wilber F. Burt, Arthur E. Pew Jr., and W. A. Peters Jr. “Catalytic Processing of Petroleum Hydrocarbons by the Houdry Process.” Proceedings of the American Petroleum Institute 19, no. 3 (1938): 133–148.

“Practical Catalysis and Its Impact on Our Generation.” In Advances in Catalysis, vol. 9, edited by Adalbert Farkas. New York: Academic Press, 1957.

“Développements et Tendances de la Catalyse Industrielle.” In Actes du Deuxième Congres International de Catalyse. Paris: Technip, 1960.


Enos, John Lawrence. Petroleum Progress and Profits: A History of Process Innovation. Cambridge, MA: MIT Press, 1962. See chapter 4.

McEvoy, James E. “Citizen Houdry.” CHEMTECH 26 (February 1996): 6–10.

Mills, G. Alex. “Catalysis: The Craft according to Houdry.” CHEMTECH 16 (February 1986): 72–75.

Moseley, Charles G. “Eugene Houdry, Catalytic Cracking, and World War II Aviation Gasoline.” Journal of Chemical Education 61 (August 1984): 65–66.

Oblad, Alex G. “The Contributions of Eugene J. Houdry to the Development of Catalytic Cracking.” In Heterogeneous Catalysis: Selected American Histories, edited by Burton H. Davis and William P. Hettinger Jr. Washington, DC: American Chemical Society, 1983.

Spitz, Peter H. Petrochemicals: The Rise of an Industry. New York: Wiley, 1988.

John K. Smith

About this article

Houdry, Eugène Jules

Updated About encyclopedia.com content Print Article