SPECIAL PUBLICATION NO. 27


peat coke A carbon residue produced by the pyrolysis of peat which
is a raw material for the production of activated carbon, in the production
of high purity silicon and in the production of ferrochrome and ferrosili-
con alloys.

peat-humus (American Society of Testing and Materials (ASTM)
classification) Peat which contains less than 33.33 percent plant fiber.
NOTE: ASTM is presently in the process of revising this classification;
the above term will no longer be used.

peat resin A peat bitumen, a byproduct of peat wax production uti-
lized primarily as a source of steroids for use by the pharmaceutical
industry.

peat tar A water immiscible condensate produced by the pyrolysis of
peat. It is often recycled as fuel for the coking pyrolysiss) process.

peat wax See peat bitumen.

petroleum ether A flammable, low boiling point, hydrocarbon mixture
produced by the fractional distillation of petroleum, used as a solvent.

pH The negative logarithm of the hydrogen ion activity (less correctly
concentration), indicates the acidity or alkalinity of a substance.

phenol A white poisonous substance, C6HOH, derived from coal or
peat tar or as a derivative of benzene; used primarily as a disinfectant, as
an antiseptic and in organic synthesis; also called carbolic acid.

physiognomy External aspect; characteristic or quality as revealed
outwardly.

polynuclear aromatic hydrocarbons Nonmethane hydrocarbons pro-
duced by the incomplete combustion of peat; they are carcinogenic at
very low levels and are stable in the environment.

potassium dichromate An orange-red poisonous powder, K2Cr207,
used as a laboratory reagent, in dyeing and in photographic chemicals.

power gas Gas utilized as fuel.

proximate analysis The determination of moisture, volatile matter,
fixed carbon, and ash using procedures prescribed by the American Soci-
ety of Testing and Materials.

pulverized fired boiler A boiler design which uses fuel which has been
finely ground.