BUREAU OF GEOLOGY


treated for disposal. Excess water is recycled to the fermenter (U.S.
Department of Energy, 1979).

 Industrial Chemicals

 Peat has been utilized as a raw material for the production of industrial
chemicals for many years in Europe and the Soviet Union. U.S. interest
has developed only recently. Peat bitumens, carbohydrates and humic
acids are extracted by processes at low to moderate temperatures. Peat
coke, peat tar and activated charcoal are produced by pyrolysis. The use
of peat for industrial chemicals does not pose major technical problems.
The technology has been developed in Europe and the Soviet Union. The
chemicals produced are similar to petroleum derived products. As petro-
leum becomes more expensive, the incentives to utilize peat will increase
(Minnesota DNR, 1981).

 BITUMENS

 Peat bitumens are those peat components which are soluble in nonpo-
lar organic solvents. The yield of bitumens depends on the extracting
solvent chosen. Yield increases from low to high in the following list of
solvents: petroleum ether, gasoline, dichloroethane, benzene,
ethanol:benzene (1:1) (Fuchsman, 1978). Although various solvents are
utilized for analytical purposes, gasoline is the solvent used in commer-
cial processes. Benzene is not used because of health hazards
(Bel'Kevich, 1977 in Fuchsman, 1978). The peat bitumens of commer-
cial interest are peat waxes and resins. The waxes are the most impor-
tant commercially (Fuchsman, 1978).
 Peat, suitable for commercial wax production, contains at least five
percent gasoline extractable material and has an ash content less than
10 percent (Lishtvan and Korol, 1975, in Fuchsman, 1978). The wax
content of peat is higher in more highly decomposed peats (Naucke,
1966, in Fuchsman, 1978) particularly those with remains of shrubs and
trees (Fuchsman, 1978).
 Dried peat particles in the size range of 0.02 inches-0.2 inches are
required for efficient solvent extraction. Wax extraction utilizes gasoline
as the solvent and extracts most of the wax but relatively few of the
resins (Bel'Kevich, 1977, in Fuchsman, 1978). Gasoline and peat are
mixed at 20:1. Approximately five percent of the gasoline is lost in the
process, with the rest being recycled after wax removal by solvent evap-
oration.
 The crude wax contains some resins. Resins are partially removed by
treatment with an appropriate solvent (cold acetone, alcohol and ethyl
acetate) (Fuchsman, 1978). Further purification is accomplished by
treatment with potassium dichromate and sulfuric acid at
1670F-2300F. The result is a fairly hard, light tan wax (Bel'Kevich,
1977, in Fuchsman, 1978).