Hemp’s New Friends
Continued from: Hemp and The New Energy Technologies, Part One
The fulminating debate over the Hemp Question has polarized between those traditionalists (like the DEA) who maintain that the weed exists exclusively to poison children, and revisionists (like Jack Herer in The Emperor Wears No Clothes), who prophesy that hemp will be the salvation of humanity in the 21st century’s ecological crises. Jon Gettman, in his ongoing series on the practical economics and geopolitics of hemp’s irresistible industrial development, cleaves to a middle view: Money will be made from this plant in the near future, big money, legal money, and here’s exactly how it will come to pass.
In 1927, journalist Wheeler McMillen prophesied in Farm And Fireside magazine: “Perhaps already you button your shirt and comb your hair with milk from your own cows. Some of these days — not yet, but in time — you may run your tractor and automobile with your own grain and potatoes, paint your buildings with your own soybeans, read magazines and newspapers printed on your own cornstalks and straw and listen through radio horns and telephone receivers made out of your own corncobs and oat hulls.”
McMillen was a pioneer in advancing utilization research in the United States in the 20th century. Currently we are fortunate enough to be living in an era in which his vision is taking shape before our very eyes, as our country develops brilliant new industrial uses for both traditional and novel planetary resources. The development of these resources as ‘feedstocks’ for industry and commerce — for new textiles, fuels, nontoxic industrial agents, foods and medicines — is proceeding apace, and as we showed here in Part One of this series, cannabis hemp will inevitably be recognized as a major element in this 21st-century industrial revolution.
The United States is committed to developing several agricultural sources for industrial raw materials, and any hope of reintroducing hemp here rests with the success of this broad program. First, let’s look at several novel plants currently in development for industrial uses, and see how they stack up next to hemp.
The alternative crops now in development fall into three categories: seed-oil, rubber and fiber crops. Vegetable seed-oils contain triglycerides, a chemical combination of glycerol and fatty acids, which are industrially transformed into thousands of products. The oils that dominate world trade contain palmitic (16:0), stearic (18:0), oleic (18:1) and linoleum acids (18:2). The numbering system designates the number of carbon atoms, followed by the number of double bonds in the molecular organization. Hemp oil, it turns out, contains high concentrations of linoleic acid (18:2) and linolenic acid (18:3) — the two most prevalent polyunsaturated fatty acids used in industry.
Jojoba, lesquerella, rapeseed and crambe are occasionally described as oils with superior characteristics to hempseed oil, and consequently as reasons why there is no need to encourage hemp cultivation as a seed-oil feedstock. But these oils have different compositions from hempseed oil, which is primarily composed of polyunsaturated fatty acids. Each of these oils has individual strengths revealed through basic and applied research. Lesquerella is a source of ricinoleic acid, rapeseed a source for erucic acid and jojoba a replacement for sperm-whale oil. Vegetable oils consist of various combinations of all three types of fatty acids. Soybean oil consists of 55 percent linoleic acid and 7 percent linolenic acid; rapeseed oil is 20 percent linoleic and 55 percent linolenic acid. Hempseed oil is 43 percent linoleic and 21 percent linolenic acid.
The economics of the seed-oil market will be influenced by the baseline value of any seed oil as a biodiesel source and/or the value of other specific byproducts. Castor oil, for example, when used as a lubricant, is unaffected by petroleum solvents and remains stable under extremes of heat, cold and pressure. Its key ingredients, ricinoleic and sebacic acids, have been classified as strategic materials by the Department of Defense.
The United States imports 75 million pounds of castor oil annually from Brazil and India. Therefore, the Department of Agriculture is supporting attempts to grow castor-bean plants and a new crop, lesquerella, in the Southwest. Lesquerella oil contains fatty acids similar but not identical to the ricinoleic acid in castor oil. Like castor oil, it has use as a feedstock for nylon, plastics, soaps and detergents.
Rapeseed oil is currently imported from Canada and Eastern Europe. The USA spends $10 million annually on 40 million pounds of rapeseed oil used in plastic film, as an automotive and industrial lubricant and as cutting oils. The food-use version is produced by the crambe plant and is known as canola oil.
Industrial rapeseed and crambe oil contain large amounts of a long-carbon-chain erucic acid that is used in plastic trash bags, zip-lock sandwich bags and transmission-fluid additives. In addition to use as a feedstock for biodiesel fuel, new uses for rapeseed oil include paints and coatings, nylon-1313, plastics and hard waxes.
The meal produced from rapeseed-oil extraction, like castor meal, contains unhealthy glucosinolates. While these natural pesticides make it useful as a fertilizer, commercial development requires further research to make it a healthy feed for livestock. Detoxification technologies are being tested on both castor and lesquerella meal, and will enable other protein-rich oil byproducts (like hemp’s) to compete in the feed-meal market.
Jojoba (pronounced “ho-ho-ba”) oil, derived from the jojoba bean, is a substitute for sperm-whale oil, as both are natural liquid oils with similar properties, though jojoba oil has greater purity. Cosmetics and toiletries account for 90 percent of jojoba-oil use today. A perennial evergreen with a life expectancy of 40 years, jojoba does well in the arid Southwest, though it takes three to five years to mature before the first harvest. The current US production of jojoba is 2,500 tons of seed from 15,000 acres of bushes. The seeds are 50 percent oil, and eight-year-old plants yield 1,200 pounds per acre. The USA exports 70 percent of the jojoba oil produced in each year.
The potential uses of jojoba oil include pharmaceuticals, cosmetics, lubricants, wax replacements, printing inks, paint, linoleum, varnishes and antifoam agents. Competitors for the USA include jojoba producers in Argentina, Australia, Brazil, Israel, Paraguay and Peru.
Kenaf, an annual hibiscus fiber-plant grown in the Southwest as a source of newsprint pulp (and also for rope, twine, sackage and poultry litter), has also been held out as superior to hemp in terms of biomass and fiber. Kenaf yields six to eight tons of pulp per acre, and could replace $6 billion in newsprint imports. Current acreage is 4,100 acres, and this could grow to 5,000,000 acres over the next 20 years. A kenaf harvester has been designed, and other advances in processing this bast-fiber plant could aid in the processing of hemp. It is also grown in the former Soviet Union, in India, China, Taiwan, Iran, Nigeria, Thailand and elsewhere.
Gayule (pronounced “gwa-yoo-le”), a perennial shrub fond of the Southwest, is a source of natural rubber. The United States imports $1 billion of natural rubber from Southeast Asia annually for a lot of products, including high-performance tires for military aircraft. Forecasters expect a rubber shortage over the next 10 years as plantations in Southeast Asia switch to coconut and oil-palm crops.
Forty years ago, many believed that synthetic rubber would replace the need for natural rubber completely. They were wrong. Natural rubber is better, and so are many of the products derived from renewable agricultural crops. The benefits derived from these renewable crops, including hemp, depend on emerging technologies that enhance their value.
New Uses for Old Crops
The introduction of new crops as industrial feedstocks should not be viewed as reasons to neglect development of hemp for these purposes, any more than new methods of exploiting traditional crops should be regarded as unusable for the exploitation of hemp. Indeed, the historical experience of many of these crops virtually ordains the resumption of hemp development in the immediate future to exploit its unique, and uniquely varied, industrial potential.
Soybeans represent one of American agriculture’s major success stories. Before World War II, the USA imported 40 percent of the fats and oils it used. Having planted 15.6 million acres of soybeans in 1950, the nation now grows 58 million acres of soybeans a year, producing 91 billion pounds of soybean meal and 21 billion pounds of vegetable oil. An acre of soybeans produces about 33 bushels, which provide 350 pounds of oil per acre.
Soybean oil is high in linoleic acid, as is hemp oil, providing a feedstock for the production of plasticizers (for pliability), stabilizers (to resist chemical change), emulsifiers (to help mix unmixable liquids), surfactants (to reduce surface tension of liquids and metals) and other fundamental industrial products. Enzymes and microorganisms can be used to convert the fatty acids in soybean oil to other valuable acids, such as ricinoleic acid, previously available only in imported castor oil.
Soy-based ink is rapidly gaining use as an alternative to petroleum-based inks. The US government announced plans in 1994 to use soy-based inks for most of its own considerable printing operations. Economics make soybean the oil of choice at the present time, but many soy-related products can be derived from other seed-oil sources, like hemp.
Corn is 72 percent carbohydrates. Most corn is grown as feed grain for livestock and to provide byproducts such as corn oil and cornstarch. An acre of corn yields an average of 113 bushels, and every bushel of corn contains 40 pounds of cornstarch. The starch is used for corn syrup and ethanol. Like cellulose, starch is composed of natural sugars. These sugars are absorbent, and research is under way to maximize this absorbency potential in diapers, filters and batteries. Corn oil is a feedstock for plastics and other products.
The corn stalk is 47 percent crude fiber, the cobs are 37 percent fiber and corn stover (leaves) are 37 percent fiber. Research is under way at Department of Energy laboratories to develop microoganisms that will detach crude cellulosic fibers from the lignin, or natural glue, which holds the plant together; this will enable more of the entire plant to be used as biomass for energy production.
The purpose of new uses for corn and corn products is to provide long-term stability for corn prices by increasing demand. Yet if demand for corn is increased too much, it could increase other food prices. (Corn is used to feed livestock, and so rising corn prices will increase the cost of meat.) New technologies for corn products provide new uses for corn, but more important, they provide new uses for raw materials that are derived from corn — natural sugars and fibers — which can also be derived from hemp.
Starch from any source can be used to create biodegradable plastics and ethanol. Carbonless paper relies on encapsulated ink made from wheat starch. Recently, scientists have been able to separate wheat starch into large and small component starch granules. Upon separation, the small granules can be used as a feedstock for fully biodegradable plastics, industrial chemicals, capsules for medicines and cosmetics. The market will decide the prices for various commodities as starch feedstocks for industrial raw materials, whether they be corn, wheat, potatoes, potato peelings, hemp or sugarcane.
The nonfood uses of dairy products will amaze anyone outside the state of Wisconsin. According to the USDA, “Milk components can be used in manufacturing such products as: alcohol, lactic or acetic acids, penicillin, polyurethane foam for use in insulation and packaging materials, urea-formaldehyde resin adhesives, emulsion stabilizers, fat replacements in food, premium paper coatings, photographic film, edible-protein packaging films, nontoxic industrial lubricants for food-manufacturing equipment, water repellents, emulsifiers and gels.” And most of the same components that can be extracted from raw milk for these industrial purposes — starches, fatty acids, etc. — can also be extracted from raw hemp.
New Technologies for Hemp
Clearly, there is an agri-techno revolution underway. Give our scientists a plant that will grow abundantly in the United States, and they’ll figure out how to use that plant to provide Americans with work and disposable income. The technological advances under way to provide new uses for traditional crops and to utilize new crops for industrial materials provide numerous new applications for the cellulose and vegetable oil produced by the cannabis plant. There is no better argument that it is now time for the US government to resume basic and applied research into the industrial uses of the raw materials produced by the hemp plant.
Who really knows what products and applications can be derived from hemp until it can be properly studied and analyzed? The new crops and technologies reviewed above indicate great promise for cellulose, starch, and seed-oil crops as industrial feedstocks. Hemp stalks contain 77 percent cellulose and hemicellulose; hemp seeds contain 35 percent oil that is high in polyunsaturated fatty acids.
Starch and cellulose are alike composed of glucose chains. Starch has different linkages than cellulose, making it more water-soluble and thus digestible by humans. Plant-derived cellulose derivatives are already in use in the United States in a variety of applications, including use as thickeners, binders, stabilizers, suspending agents and flow-control agents. Carboxymethylcellulose (CMC) is used in biotechnology for separating molecules. Another derivative, hydroxyethylcellulose (HEC) is used by the oil industry as a thickener in drilling fluids. Hydroxypropyl-methylcellulose (HPMC) is being investigated as an agent to lower blood-cholesterol levels.
As reviewed in Part One of this series, various acid and enzymatic treatments are being developed to convert cellulose into ethanol. According to the federal Office of Technology Assessment, “Cellulose will no doubt continue to be a major material feedstock for a wide spectrum of industries. Future research is likely to focus on the development of new chemical derivatives and the creation of composites that combine cellulose with other biodegradable materials.” For example, modified cellulose sutures may be available to surgeons in the near future, as will other medical products such as novel drug-delivery systems.
Then there’s the lignin which provides structural support to plant-cell walls. Vanillin, the principal ingredient in artificial vanilla, is derived from lignin, and so is a lot more. Thanks to their natural adhesive characteristics, lignosulfates are used for road-dust control, as molding agents and in animal feed. Lignin derivatives are used to prevent mineral buildup in cooling towers and as dispersing agents in pesticide powders. There is also the potential to use lignin as a feedstock for plastic manufacture. Hemp, of course, is rife with lignin.
Hemp, The Multi-Use Crop
The agricultural market is exceedingly complex, but inevitably gives way to larger market realities. The ultimate answer to all predictions, though, is to let the market decide. In the case of hemp, the question is not whether it can compete or not in the modern market, but when will the government let the market decide for itself?
Hemp grows in more diverse ecosystems than many of the crops reviewed above. For example, while few of the new crops in development will grow in the Shenandoah Valley of Virginia, hemp certainly will. Hemp has always flourished throughout the United States.
Kenaf may produce more fiber than hemp, but it only grows in the Southwest. Rapeseed may produce more oil, but it is dedicated for high erucic-acid-dependent use. Corn may produce ethanol more economically, but increasing demand for corn will increase food prices across the board.
Unlike many alternative crops now in development, hemp can provide two commodities for the price of one — cellulose and seed oil.
Corn will bring a farmer $265 in gross revenue per acre farmed (based on average yields of 113 bushels per acre and current prices of $2.35 per bushel). Wood chips currently bring five cents per pound as a feedstock, while vegetable oilseeds sell for over 20 cents. Hemp as a source of crude raw materials will provide more revenue per acre than corn at half these prices. Ignoring the value of the hemp fiber for textile fabric, an acre of hemp will produce 8,000 pounds of dry cellulosic biomass. Seed yields from an acre of hemp are estimated at 1,300 pounds. At 2.5 cents per pound for the biomass and 10 cents per pound for the seeds, an acre of hemp provides $330 in revenue, or $65 more than corn.
It is true that hemp grown for biomass would be harvested before the female flowers produce mature seeds for the planting of the next season’s crop; otherwise the male plants, which die earlier than the females, might be lost or damaged. But a self-pollinating hemp plant has already been developed, and who knows what else will be produced by breeding and genetic engineering?
In any event, if the plant has compelling value at half of its competitors’ prices, doesn’t that indicate some promising potential?
The ideal nonmedical utilization of the hemp plant is as follows: The flowers contain seeds with 35 percent oil, to be used for fuel and as a source of epoxy fatty acids for plastics and other industrial products. The oil-extracted meal is used as feed for livestock or as fertilizer. The leaves of the plant are left on-site as natural nitrogen to replenish the soil. The stalks are harvested and have their high-quality bast fibers removed for specialized textile use, and the remaining hurds (over three tons per acre of high-cellulose-content chips) are used as a biomass feedstock for ethanol and other cellulosic applications.
Developing technologies will process the hemp oil into diesel fuel, using microemulsification, pyrolysis or transesterification. Various enzymes and microorganisms are being developed to make the conversion of the stalks and/or hurds into sugars and ethanol more economically efficient. Technology developed to provide new uses for crops as sources for industrial raw materials will provide the means for farmers to realize new economic security by growing hemp in 21st-century America.
A major source for this article is the USDA publication New Industrial Uses, New Markets for US Crops: Status of Technology and Commercial Adoption, prepared by Jonathan Harsch for the Cooperative State Research Service.
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