Squeezing oil from acres of milkweed in Utah
They are growing petroleum in Utah. Chemists at Salt Lake City's Plant Resources Institute have extracted petroleum and synthetic fuels from the harvest of a half-acre lot plot of common milkweed plant using a simple solvent process.
Work began two years ago with a $100,000 grant from a regional representative of the Department of Commerce. The project's success has since attracted the attention of the US Department of Energy (DOE). An 18-month contract that calls for a substantial increase in research is pending between the institute and the DOE. At least one major oil company is said to be "intensely interested" in the current findings, and is exploring the possibilities of large-scale production.
Milkweed plants convert light energy from the sun into hydrocarbons (the organic compound that occurs in petroleum) through photosynthesis. The petroleum is contained largely in the white fluid of the plant's stem. A sizable portion of the world's supply of crude oil comes from vegetation trapped underground for millions of years and liquefied under intense pressure. using modern but uncomplicated laboratory techniques, researchers at the Plant Resources Institute are bypassing this natural process and exploring directly the organic origins of petroleum.
Milkweed-derived petroleum can be produced with already existing equipment, both in the lab and on the farm. According to Mike Adler, president of Plant Resources Institute, "slightly modified alfalfa machinery" is all that is needed to seed and harvest the milkweed. In the lab, a solvent commonly used to extract soybean oil is needed to the dried and pulverized milkweed. The petroleum is separated and the solvent can be used again.
The yield for one acre includes 200 gallons of oil, 300 gallons of ethanol, and500 gallons of methanol, As a bonus, the process also separates small amounts of natural rubber and resins, wax, and a high protein residue for livestock feed. The chemical compounds in the milkweed oil make it highly adaptive for use in plastic and other synthetic products. The value of the various derivatives has been estimated to be $1,000 per acre.
A main concern of the forthcoming contract between the DOE and the Plant Resources Institute is the economic feasibility of large-scale milkweed production. Under terms of the agreement, the size of the crop will be increased to 10 acres, and concern will be given to further refining laboratory techniques.
Research in the field of hydrocarbon producing plants was pioneered by Melvin Calvin at the University of California, Berkeley. Mr. Calvin is a proponent of milkweed petroleum production for the purpose of fueling automobiles, and first advised the Plant Resources Institute to take up the study of milkweed. Other research is being done at universities and companies in Arizona and Texas, and at the USDA's Norther Research Laboratories in Peoria, Ill. The Utah institute, though, is the first to actually conduct a farming demonstration.
Northern Research Laboratories is currently setting priorities for the renewble resource capability of some 265 varieties of hydrocarbon-producing plants to determine which one will achieve the highest yield on a long-term basis. Plants similar to milkweed grow all over the country, and other research is concentrating on finding the species best suited for particular environments.
After the original planting, milkweed continues to grow season after season. The Plant Resources Institute obtained two cuttings the first summer, and three this past season on a plot in norther Utah. It is believed that yields will continue to increase for several more seasons as the plants further mature.
Originally, it was hoped that the milkweed could be planted on arid land not under cultivation. While the stress of a harsh environment "is what produces the hydrocarbos," Mr. Adler admits "some water" is needed for proper growth. If milkweed is limited to land normally reserved for other crops, it may make growing the plant unprofitable. Sarah Srague of the DOE says some researchers have already concluded that the only economically viable byproducts from milkweed are the synthetic fuels and the livestock feed.