Historical Production and Use of Carbon Materials*
||Earliest known use by the Egyptians and Sumerians. Wood chars (charcoal)
used for the reduction of copper, zinc and tin ores in the manufacture
of bronze. Charcoal also used as domestic smokeless fuel.
||The first recorded application of charcoal for medicinal purposes was
cited in Egyptian papyri. The principle use appears to have been the application
of charcoal to adsorb odorous vapours from putrefying wounds and from
within the intestinal tract.
||Hippocrates and Pliny record the use of charcoal to treat a wide range
of complaints including epilepsy, chlorosis and anthrax.
||Recent studies of the wrecks of Phoenician trading ships suggest that
drinking water was stored in charred wooden barrels. This practice was
certainly still in use in the 18th Century for extending the use of potable
water on long sea voyages. Hindu documents of the same period (450 BC)
also refer to the use of sand and charcoal filters for the purification
of drinking water.
||Claudius Galvanometer 500 medical treatises, many of them referring
to the use of carbons of both vegetable and animal origin for the treatment
of a wide range of diseases.
||Roman Emperor Diocletian ordered the total destruction of all scientific
books within the Roman Empire, thereby setting back the progress of science
within Europe by at least 1000 years.
||The specific adsorptive powers of carbons (i.e. charcoal) were recognized
by Scheele, who measured the volumes of various gases that could be adsorbed
by carbons derived from different sources.
||It was reported that heat effects are associated with the adsorption
of gases by charcoal. This is significant in that it led later to the
"condensation theories of adsorption".
||Lowitz reviewed the known abilities of charcoals to adsorb odours emanating
from medical conditions and published accounts of their ability to adsorb
vapours from a range of organic chemicals. In addition, he studied the
effectiveness of charcoal in decolorizing various aqueous solutions and,
in particular, its commercial application to the production of tartaric
acid. This appears to be the first systematic account of the adsorptive
power of charcoal in the liquid phase. At this time, too, the developing
sugar refining industry was looking for an effective means of decolorizing
raw sugar syrups. However, the wood charcoals available at this time were
not particularly effective in this role, presumably because their porosity
had not been developed beyond the extent produced by carbonization.
||Kehl discussed the use of chars for the control of odours from gangrenous
ulcers and discovered that carbon prepared from animal tissues could be
used for removing colours from solution.
||An English sugar refinery successfully used wood charcoal for the decolorization
of sugar syrups but kept the method of preparing the carbon a secret.
||Gruillon introduced the first large-scale sugar refining facility in
France using ground and washed wood charcoal for decolorizing syrups.
||Delessert successfully demonstrated the use of charcoal for decolorizing
sugar-beet liquor. He was directly responsible for the growth of the sugar
beet industry in France. By 1808 all sugar refineries in Europe used charcoal
as a decolorizer.
||Figuier discovered the greatly enhanced decolorizing capability of bone
char compared with wood char. The sugar refining industry was quick to
substitute bone char for wood char. Methods of regenerating the bone char
by heating were discovered, and shortly afterwards a granulated bone char
was developed which could be much more readily regenerated.
||By this date most of the sugar refining industry had switched to the
use of granulated bone char as a decolorant.
||Joseph de Cavaillon patented a method of regenerating used bone chars.
The method was not entirely successful.
||Bussy demonstrated that the decolorizing properties of carbons were
inherent to the source material and also depended on the thermal processing
and the particle size of the finished product. He demonstrated that carbonization
at too high a temperature, or for too long, reduced the adsorptive properties
and that porosity was important, although he had no means to measure this
factor. He also heated blood with potash to produce a carbon with 20-50
times the decolorizing power of bone char. This is the first recorded
example of producing an activated carbon by a combination of thermal and
||Schatten systematized the use of a hydrochloric acid wash prior to heating
in the regeneration of bones chars. This effectively removed the minerals
salts adsorbed on to the carbon. He also introduced in Germany the first
continuous process vertical kiln for the manufacture and regeneration
of bone chars.
||Stenhouse described the successful application of carbon filters for
removing vapours and gases in the ventilation of London sewers.
||Lipscombe prepared a carbon to purify potable water.
||Hunter discovered the excellent gas adsorbent properties of carbons
derived from coconut shells.
||Winser and Swindells heated paper mill waste with phosphates. Many of
their disclosures are relevant to processes now in industrial use. They
were not developed on a commercial scale because of engineering difficulties.
||Kayser first used the term 'adsorption' to describe the uptake of gases
||Von Ostrejko set the basis for the commercial development of activated
carbons through processes involving (a) the incorporation of metallic
chlorides with carbonaceous material before carbonization and (b) the
mild oxidation of charred materials with carbon dioxide or steam at raised
||Marketing of first industrially produced activated carbon, 'Eponit"
(trade name), by the Fanto Works, Austria. They adopted von Ostrejko's
gasification approach in the manufacture of Eponit from wood. It was marketed
as a decolorizer for the sugar-refining industry. Until this time the
principle user of active carbons was the sugar-refining industry and manufacturers
produced active carbon by their own secret or patented process. All the
principal types of reactor with the exception of the fluidized bed were
by then in use.
||Wunsch heated a mixture of Eponit and zinc chloride and found that the
decolorizing capacity of the reactivated material was greatly increased.
Wunsch went on to prepare other active carbons with superior properties
to those of Eponit by substituting wood and other carbon precursors for
Eponit in his process. The zinc chloride process was used for many years,
sometimes in combination with steam or carbon dioxide activation. It has
now been largely superseded by the use of phosphoric acid as the chemical
||The introduction of poisonous gases into the battlefields of the First
World War gave great impetus to the development of large-scale production
methods for adsorbent carbons suitable for use in military respirators.
Granulated carbons, with adequate adsorptive powers and providing low
resistance to air flow through the respirator canister, were developed
by activating wood chips with zinc chloride. These were first manufactured
carbons with reliably controlled adsorptive and physical properties. A
group studying under Chaney in the USA examined a wide range of precursors
intended to produce adsorbents for gas-mask canisters. They determined
that coconut shell yielded the best combination of required characteristics
in the resulting carbon.
||The wartime developments to mass-produce activated carbons with closely
controlled characteristics lead to post-war expansion in the commercial
production and application of carbons. In Europe considerable progress
was made in the manufacture of active carbon from new raw materials. Coconut
and almond shells with zinc chloride, yielded active carbons with high
mechanical strengths and adsorptive capacities for gases and vapours.
||In Czechoslovakia two varieties of pelletized carbons were produced
from sawdust by zinc chloride activation, for the recovery of volatile
solvents and for the removal of benzene from town gas. Mecklenburg, working
on the dynamics of adsorption, and Kubelka, who interpreted sorption phenomena
on active carbon by the mechanism of capillary condensation, developed
a method for calculating the distribution of pore diameters in active
carbon. The published a theoretical interpretation for the service time
of a filter charged with active carbon. This theory and its mathematical
development are now obsolete, but at the time represented a significant
contribution in the field.