Page 25 - Academic Press Encyclopedia of Physical Science and Technology 3rd BioTechnology

P1: GNH 2nd Revised Pages
Encyclopedia of Physical Science and Technology EN002G-61 May 19, 2001 19:33

150 Biomass, Bioengineering of

refining industry was developed over about the last 120 and economic benefits are also key factors driving the
years and catalyzed the development of a huge chemical adoption of soybean oil-based inks. These soybased inks
industry, based mostly on petroleum as the ultimate raw were introduced in the 1970s in response to oil shortages
material. Today in the United States, the chemical process and now account for about 40% of all inks.
industries have total sales of over $360 billion per year In the United States, approximately 100 million tons
and the petroleum refining industry is worth about $250 per year of organic chemicals are produced annually, with
billion per year. much less than 10% of these chemicals currently de-
Use of biomass for chemicals and materials is relatively rived from biomass. It seems likely that chemical uses
small, apart from building materials (wood products). In of biomass will grow fastest among these or other or-
the United States, more than 90% of total organic chemi- ganic chemicals, particularly for those chemicals that con-
cal production is based on fossil feedstocks. Biomass ac- tain oxygen. Some examples of these oxygenated chem-
counts for less than 1% of all liquid fuels, essentially all icals include organic acids and their derivatives (acetic,
of it ethanol derived from corn. Approximately 7% of the adipic, lactic and succinic acids and maleic anhydride),
total U.S. corn crop is processed into fuel ethanol, in- alcohols (butanol, isopropanol, propanediol, and butane-
dustrial starches, industrial ethanol and other chemicals. diol) and ketones (acetone, methyl ethyl ketone). Indeed,
Not withstanding the relatively small size of the biomass- the Cargill–Dow joint venture is focused on polymer pro-
derived chemicals and fuels industry, this industry pro- duction from lactic acid while the DuPont venture with
duces a very wide range of products including oils, inks, Tate and Lyle is focused on 1, 3 propanediol as another
pigments, dyes, adhesives, lubricants, surfactants, organic polymer feedstock.
acids and many other compounds. Therefore, bioplastics may prove to be the most rapidly
As we have seen, biomass is relatively low cost. How- growing new materials application for biomass. Indus-
ever, the processes for converting biomass to industrial trial starches, fatty acids, and vegetable oils can serve as
products are not, in general, well enough developed or raw materials for bioplastics, including polymer compos-
low cost enough to compete effectively with comparable ite materials. Waste paper and crop and forest wastes and
petroleum-derived products. Petroleum-derived products virgin materials are being used as the basis of new com-
are supported by over a century of research, development posite materials and new fabrics, including Tencel, the first
and commercial experience. However, the competitive po- new textile fiber to be introduced in 30 years.
sition of biomass is beginning to change. This change is It is instructive to consider the amount of plant matter
being driven by a combination of technical, economic and that might be consumed by new chemicals and materials
social/political factors. Several recent authoritative reports uses of biomass. Given total U.S. production of about 100
suggest a gradual shift over this next century to a much million tons of organic chemicals annually, this is about
larger fraction of fuels, chemicals and materials derived one third of the total mass of the U.S. corn crop of ap-
from biomass. proximately ten billion bushels per year. The corn residue
or stover that might be converted to various products to
substitute for or replace these organic chemicals is easily
B. New and Developing Uses of Biomass equal to the total mass of these organic chemicals, even
without converting any of the corn itself. Furthermore,
1. New Chemicals and Materials Uses
corn yields continue to increase.
From 1983 to 1994, the sales of some biomass-derived If we assume a 1% per year increase in yield for corn
products (fuel and industrial ethanol, corn syrups, citric (versus 3% per year over the past 50 years) and no change
acid, amino acids, enzymes and specialty chemicals, but in the planted acreage, then the annual increase in corn
excluding pharmaceutical products) rose from about $5.4 produced is about 100 million bushels per year, or over 2
billion to approximately $11 billion. These products seem million metric tons of new corn every year. The Cargill–
likely to continue to grow. The market for new and exist- Dow Polymers plant being opened in Blair, Nebraska, in
ing enzymes may be particularly strong, given the abil- late 2001 will produce 140,000 metric tons per year of
ity of enzymes to transform biomass into new products polylactic acid from approximately 200,000 metric tons
and to provide more environmentally clean chemistries of corn. That is, a new large scale plant for bioplastics will
for older petroleum-derived products and processes. En- only use about 10% of one year’s increase in the corn crop.
zymes also have growing applications to improve envi- Thus it seems unlikely that biomass use for chemicals and
ronmental quality while reducing costs in selected agri- materials will really have much effect on grain supplies
cultural and domestic uses (e.g., animal feed processing and prices. However, this does not hold true for new large
and detergents). Enhanced environmental compatibility scale liquid fuel uses of biomass.