450 MINERALS YEARBOOK

catalyst of iron-nickel and yielded 1.7 liters of benzol containing light
oils. A large-scale experimental plant has been mstalled at the nitrogen
plant of the "Ruhr-Chemie" at Holton in the Ruhr district.9'
 Synthetic gasoline from water gas at atmospheric préssure.—The
production of synthetic gasoline by passing mixtures of hydrogen and carbon
monoxide at atmospheric pressure over iron or cobalt catalysts at approximately
2600. C., reported by Fischer and Tropsch 92 in 1926, has not reached commercial
realization, although a semicommercial scale plant at the Mulheim Coal Research
Institute has been operating experimentally during the past few years. The
earlier cobalt catalyzers have been superseded by nickel-manganese-aluminum
oxide on kieselguhr.9' This catalyzer gave yields of 100 to120 cm of liquid
products per cubic meter of gas during 4 weeks of continuous operation. The
yield then had decreased to 30 percent of the initial value. The catalyst
must be regenerated by removing the accumulated paraffin. The optimum reaction
temperature ranges from 190° at the beginning of a run to 210° C.
at the end. The principal difficulties in large-scale commercial operation
of the process are to dissipate the high heat of reaction and keep the catalyst
at the proper temperature; also, the gases must be purified carefully to
remove sulphur. It is believed that these problems are nearly solved.
 * SUMMARY

 A review of the world-wide technical developments in the utilization of
coal during the depressiOn years shows little tangible progress in providing
new markets for coal. In the United States continued competition by cheap
petroleum and natural gas has prevented practical application of new methods
of coal processing because of lack of adequate market for the liquid and
gaseous byproducts; therefore, low-temperature carbonization must support
itself almost wholly on the returns from low-temperature coke. The possibility
has not yet been demonstrated in the United States.
 The technical process for hydrogenating and liquefying coal is now available
and may be put to use when and if a failing petroleum supply requires oil
from coal. The process is too costly for use under present conditions.
 A number of important elements, such as ammonia, methanol, higher alcohols,
solvents, etc., are now being made from gases obtained from coal; but even
if all the ammonia and methanol consumed in the United States were made from
coal it would require only 700,000 tons per annum, or 0.15 percent of the
1930 production of bituminous coal. There seem to be no uses for coal in
sight which run into sizable tomiages other than combustion for the generation
of heat and power.
ACKNOWLEDGMENTS

 Grateful acknowledgment is made to Cli. Berthelot, of Paris, David Browiilie,
of London, and Dr. A. Thau, of Berlin-Grunewald for valuable information
on European developments in recent years.

 "Thau, A., Steinkohlenchemie und Verkehrswesen (Chemistry of Bituminous
Coal and Transportation): Jahrb. brennkrafttechnischen Geseil., vol. 13,
1932, p. 14.
 92 Fischer, Franz, and Tropsch, Hans, Die Erdhlsynthese bei gewohnlichem
Druck aus den Vergasungs produckten der Kohlen: Brennstoff-Chem., vol. 7,
1926, p. 97; see also The Synthesis of Petroleum; Proc. 1st Internat. Conf.
Bit. Coal, 1926, pp. 234—246.
 ' 3 Fischer, Franz, Roelen, Otto, and Feiszt, Walter, The Present Technical
Status of the Gasoline synthesis: Brenustoff-Chem., vol. 13, 1932, pp. 461—468;
see also pp. 412—13; pp. 428-434; pp. 421—428.