ASTM D2652-94(1999)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation:D 2652–94 (Reapproved 1999)
Standard Terminology Relating to
Activated Carbon
This standard is issued under the fixed designation D 2652; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
abrasion resistance—the property of a particle to resist shapes of the particles, gas pockets, wall effects, and other
attrition or wearing away by friction. causes.
absorption—a process in which fluid molecules are taken up chemical adsorption— see chemisorption.
by a liquid or solid and distributed throughout the body of chemisorption (chemical adsorption)—the binding of an
that liquid or solid. adsorbate to the surface of a solid by forces whose energy
accelerated adsorption tests—adsorption tests in which the levels approximate those of a chemical bond.
end point is hastened by testing at conditions more severe coadsorption—the adsorption of two or more components on
than those anticipated in service. an adsorbent, each affecting the adsorbability of the other.
accelerated service life—the elapsed time until the end point contact batch operation—an adsorption process in which an
is reached in an accelerated adsorption test. adsorbent is dispersed in a fluid to be treated and then
acid-extractable material—substances dissolved by an acid separated when practical equilibrium is attained.
under specified conditions. continuous moving bed—an adsorption process characterized
activated carbon—a family of carbonaceous substances by flow of a fluid through a continuously moving bed of
manufactured by processes that develop adsorptive proper- granular adsorbent with continuous withdrawal of spent
ties. adsorbent and continuous addition of reprocessed or virgin
activation—any process whereby a substance is treated to adsorbent.
develop adsorptive properties. countercurrent adsorption—an adsorption process in which
activity—a generic term used to describe the capacity to the flow of fluid is in a direction opposite to the movement
adsorb in general; also, the adsorptive capacity of an of the adsorbent.
adsorbent as measured by a standard test. critical bed depth—the minimum depth of an adsorbent bed
adsorbate—any substance that is or can be adsorbed. required to contain the mass transfer zone.
adsorbent—any solid having the ability to concentrate signifi- crushing strength—the property of a particle to resist physical
cant quantities of other substances on its surface. breakdown when contained and subjected to a slowly
adsorption—a process in which fluid molecules are concen- increasing continuously applied force.
trated on a surface by chemical or physical forces, or both. degassing—removal of gases.
adsorption wave—see mass transfer zone. density, absolute or true—the mass under specified condi-
adsorption zone—see mass transfer zone. tions of a unit volume of a solid sorbent excluding its pore
ash—residue after the combustion of a substance under speci- volume and inter-particle voids.
fied conditions. density, apparent (density, bulk)—the mass under specified
as is basis—as received. conditions of a unit volume of a solid sorbent including its
breakpoint—the appearance in the effluent of a specified pore volume and inter-particle voids.
concentration of an adsorbate. density, block—see density, particle.
breakthrough—the first appearance in the effluent of an density, bulk—see density, apparent.
adsorbate of interest under specified conditions. density, particle (density, block)—the mass under specified
channeling—the greater flow of fluid through passages of conditions of a unit volume of a solid sorbent including its
lower resistance which can occur in fixed beds or columns of pore volume but excluding inter-particle voids.
particles due to nonuniform packing, irregular sizes and desorption—the separation of an adsorbate as such from a
sorbent.
differential heat of adsorption—the heat evolved during the
These definitions are under the jurisdiction of ASTM Committee D-28 on
adsorption of an incremental quantity of adsorbate at a given
Activated Carbon and are the direct responsibility of Subcommittee D28.03 on
level of adsorption.
Nomenclature and Editorial.
dosage—the quantity of substance applied per unit weight or
Current edition approved Nov. 15, 1994. Published January 1995. Originally
published as D 2652 – 67. Last previous edition D 2652 – 93. volume of the fluid being treated.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D 2652
dry basis—exclusive of any moisture which may be present. ignition temperature (kindling point)— the lowest tempera-
dust—an imprecise term referring to particulates capable of ture at which combustion will occur spontaneously under
temporary suspension in air or other gases; also, particles specified conditions.
smaller than an arbitrarily selected size. impact strength—the property of a particle to resist physical
dynamic adsorptive capacity—the quantity of a given com-
breakdown when subjected to a rapidly increasing applied
ponent adsorbed per unit of adsorbent from a fluid, or fluid force.
mixturemovingthroughafixedbedatthebreakpointforthat
integral heat of adsorption—the sum of the differential heats
component. of adsorption from zero to a given level of adsorption.
effective size—the particle size, in millimetres, which corre-
intermittent moving bed (pulse, slug)— an adsorption pro-
sponds to 10 percent finer on the cumulative particle size
cess characterized by upward flow of a fluid through a fixed
distribution curve.
bed of granular adsorbent with periodic withdrawal of spent
electrical conductivity of a particulate substance—the cur-
adsorbent from the bottom of the bed and additions of
rent flowing through a unit cross section for an imposed unit
reprocessed or virgin adsorbent to the top of the bed.
potential gradient under specified conditions of packing.
irreversible adsorption—adsorption in which the desorption
electrophoresis—migration of dispersed solid, liquid or gas-
isotherm is displaced toward higher equilibrium adsorption
eous material to one of two electrodes under the influence of
capacities from the adsorption isotherm.
an impressed direct-current voltage.
isobar—a plot of quantity adsorbed per unit of adsorbent
end point—the occurrence in the effluent of the maximum
against equilibrium temperature when concentration or pres-
permissible concentration of an adsorbate of interest.
sure is held constant.
equilibrium adsorptive capacity—the quantity of a given
isotere—a plot of equilibrium concentration or pressure
component adsorbed per unit of adsorbent from a fluid or
against temperature when the quantity adsorbed per unit of
fluid mixture at equilibrium temperature and concentration,
adsorbent is held constant.
or pressure.
isotherm—a plot of quantity adsorbed per unit of adsorbent
expanded bed—a bed of granular particles through which a
against equilibrium concentration, or pressure, when tem-
fluid flows upward at
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