1、Designation: D 2652 05aStandard Terminology Relating toActivated Carbon1This standard is issued under the fixed designation D 2652; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number in parentheses
2、indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This terminology covers terms particularly related toactivated carbon and encompasses finished products, applica-tions, and testing procedures.1.2 When any
3、of the definitions in this terminology arequoted or published out of context, editorially insert thelimiting phrase “in activated carbon” after the dash followingthe term to properly limit the field of application of the termand definition.2. Significance and Use2.1 This terminology ensures that ter
4、ms peculiar to acti-vated carbon are adequately defined so that other standards inwhich such terms are used can be understood and interpretedproperly.2.2 This terminology is useful to those who are not conver-sant with the terms related to activated carbon. However, it isalso a ready reference for t
5、hose directly associated withactivated carbon to resolve differences and ensure commonal-ity of usage, particularly in the preparation ofASTM standards.2.3 Although this terminology is intended to promote uni-formity in the usage of terms related to activated carbon, it cannever be complete because
6、new terms are constantly arising.The existence of this terminology does not preclude the use ormisuse of any term in another context.3. Terminologyabrasion resistancethe property of a particle to resistattrition or wearing away by friction.absorptiona process in which fluid molecules are taken upby
7、a liquid or solid and distributed throughout the body ofthat liquid or solid.accelerated adsorption testsadsorption tests in which theend point is hastened by testing at conditions more severethan those anticipated in service.acid-extractable materialsubstances dissolved by an acidunder specified co
8、nditions.activated carbona family of carbonaceous substancesmanufactured by processes that develop adsorptive proper-ties.activationany process whereby a substance is treated todevelop adsorptive properties.activityfor activated carbon, the adsorptive capacity of anadsorbent, usually as measured by
9、a standard test.adsorbateany substance that is adsorbed.adsorbentany solid having the ability to concentrate signifi-cant quantities of other substances on its surface.adsorptiona process in which fluid molecules are concen-trated on a surface by chemical or physical forces, or both.adsorption zones
10、ee mass transfer zone.ashresidue after the combustion of a substance under speci-fied conditions.as is basisas received.breakpointthe appearance in the effluent of a specifiedconcentration of an adsorbate.breakthrough, nthe first appearance in the effluent of anadsorbate of interest under specified
11、conditions.channelingthe preferential flow of fluid through passages oflower resistance that can occur in fixed beds or columns ofparticles owing to nonuniform packing, irregular sizes andshapes of the particles, gas pockets, wall effects, and othercauses.chemical adsorption see chemisorption.chemis
12、orption (chemical adsorption)the binding of anadsorbate to the surface of a solid at strengths approximatingthose of a chemical bond.coadsorptionthe adsorption of two or more components onan adsorbent, each affecting the adsorbability of the other.contact batch operationan adsorption process in whic
13、h anadsorbent is dispersed in a fluid to be treated and thenseparated when practical equilibrium is attained.continuous moving bedan adsorption process characterizedby flow of a fluid through a continuously moving bed ofgranular adsorbent with continuous withdrawal of spentadsorbent and continuous a
14、ddition of reprocessed or virginadsorbent.1This terminology is under the jurisdiction of ASTM Committee D28 onActivated Carbon and is the direct responsibility of Subcommittee D28.03 onNomenclature and Editorial.Current edition approved July 1, 2005. Published July 2005. Originally approvedin 1967.
15、Last previous edition approved in 2005 as D 2652 05.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.countercurrent adsorptionan adsorption process in whichthe flow of fluid is in a direction opposite to the movementof the adsorbent.c
16、ritical bed depththe minimum depth of an adsorbent bedrequired to contain the mass transfer zone.crushing strengththe property of a particle to resist physicalbreakdown when contained and subjected to a slowlyincreasing continuously applied force.degassingremoval of gases.density, absolute or trueth
17、e mass under specified condi-tions of a unit volume of a solid sorbent excluding its porevolume and inter-particle voids.density, apparent (density, bulk, packing)the mass underspecified conditions of a unit volume of a solid sorbentincluding its pore volume and inter-particle voids.density, blockse
18、e density, particle.density, bulksee density, apparent.density, packingsee density, apparent.density, particle (density, block)the mass under specifiedconditions of a unit volume of a solid sorbent including itspore volume but excluding inter-particle voids.density, tampedthe density of packed bed o
19、f powderedcarbon.desorptionthe separation of an adsorbate as such from asorbent.differential heat of adsorptionthe heat evolved during theadsorption of an incremental quantity of adsorbate at a givenlevel of adsorption.dosagethe quantity of substance applied per unit weight orvolume of the fluid bei
20、ng treated.dry basisexclusive of any moisture which may be present.dustan imprecise term referring to particulates capable oftemporary suspension in air or other gases; also, particlessmaller than an arbitrarily selected size.dynamic adsorptive capacitythe quantity of a given com-ponent adsorbed per
21、 unit of adsorbent from a fluid, or fluidmixture moving through a fixed bed at the breakpoint for thatcomponent.effective sizethe particle size, in SI units, which correspondsto 10 percent finer on the cumulative particle size distribu-tion curve.end pointthe occurrence in the effluent of the maximu
22、mpermissible concentration of an adsorbate of interest.equilibrium adsorptive capacitythe quantity of a givencomponent adsorbed per unit of adsorbent from a fluid orfluid mixture at equilibrium temperature and concentration,or pressure.expanded beda bed of granular particles through which afluid flo
23、ws upward at a rate sufficient to slightly elevate andseparate the particles without changing their relative posi-tions.fines, nparticles smaller than the smallest nominal specifiedparticle size.fixed beda stationary bed of granular particles.floatersthe material floating on the surface of water int
24、owhich carbon has been added and has been thoroughlywetted.fluidized beda bed of particles in which the fluid flowsupward at a rate sufficient to suspend the particles com-pletely and randomly in the fluid phase.Freundlich adsorption isotherma logarithmic plot of quan-tity of component adsorbed per
25、unit of adsorbent versusconcentration of that component at equilibrium and atconstant temperature, which approximates the straight linepostulated by the Freundlich adsorption equationX/M 5 kCnwhere:X = quantity adsorbed,M = quantity of adsorbent,C = concentration,k and n = constants.granular activat
26、ed carbonactivated carbon in particle sizespredominantly greater than 80 mesh.hardnessa generic term referring to the resistance of aparticle to breakdown as measured by specific tests.heat of adsorptionthe heat evolved during adsorption.hysteresis loopthe divergence between the paths of theadsorpti
27、on and desorption isotherms.ignition temperature (kindling point) the lowest tempera-ture at which combustion will occur spontaneously underspecified conditions.impact strengththe property of a particle to resist physicalbreakdown when subjected to a rapidly increasing appliedforce.integral heat of
28、adsorptionthe sum of the differential heatsof adsorption from zero to a given level of adsorption.intermittent moving bed (pulse, slug) an adsorption pro-cess characterized by upward flow of a fluid through a fixedbed of granular adsorbent with periodic withdrawal of spentadsorbent from the bottom o
29、f the bed and additions ofreprocessed or virgin adsorbent to the top of the bed.irreversible adsorptionadsorption in which the desorptionisotherm is displaced toward higher equilibrium adsorptioncapacities from the adsorption isotherm.isobara plot of quantity adsorbed per unit of adsorbentagainst eq
30、uilibrium temperature when concentration or pres-sure is held constant.isoterea plot of equilibrium concentration or pressureagainst temperature when the quantity adsorbed per unit ofadsorbent is held constant.isotherma plot of quantity adsorbed per unit of adsorbentagainst equilibrium concentration
31、, or pressure, when tem-perature is held constant.Langmuir adsorption theorythe theory that assumes thatthe surface of an adsorbent has only uniform energy sites andthat adsorption is limited to a monomolecular layer.D 2652 05a2Langmuir isotherma plot of isothermal adsorption datawhich to a reasonab
32、le degree fits the Langmuir adsorptionequation.macroporea pore with widths exceeding 50 nanometres(500 angstrom units).mass transfer zone (adsorption zone)the region in whichthe concentration of the adsorbate of interest in the fluiddecreases from influent concentration to the lowest detect-able con
33、centration.mean particle diameterthe weighted average particle size,in SI units, of a granular adsorbent computed by a standardprocedure.mesoporea pore of width between 2 and 50 nanometres (20and 500 angstrom units).microporea pore with width not exceeding 2 nanometres(20 angstrom units).moisture co
34、ntentthe water content of a substance as mea-sured under specified conditions.monomolecular layeran adsorbed film, one molecule thick.multimolecular layeran adsorbed film more than one mol-ecule thick.oven drying lossthe reduction in weight resulting when asubstance is heated in an oven under specif
35、ied conditions.pelleted activated carbona form of granular activatedcarbon consisting of cylindrical particles.physical adsorption (van der Waals adsorption)the bind-ing of an adsorbate to the surface of a solid at energiesapproximating those of condensation.pore diameterthe diameter of a pore in a
36、model in which thepores in a sorbent are assumed to be cylindrical in shape andwhich is calculated from data obtained by a specifiedprocedure.poresthe complex network of channels in the interior of aparticle of a sorbent.pore volumevolume of the pores in a unit weight of asorbent.pore volume distrib
37、utionthe distribution of pore volumesamong pores of different sizes or diameters.powdered activated carbonactivated carbon in particlesizes predominantly smaller than 80 mesh.preferential adsorptionadsorption in which one or morecomponents are adsorbed to a much greater extent thanothers.reactivatio
38、n (revivification)oxidation processes for restor-ing the adsorptive properties of a spent sorbent.regenerationdistillation or elution-type processes for restor-ing the adsorptive properties of a spent sorbent.relative efficiencythe rating of the adsorptive capacity of anadsorbent based on a comparis
39、on of its performance withthat of a reference adsorbent in a defined test.retentivitythe ability of an adsorbent to resist desorption ofan adsorbate.reversible adsorptionadsorption in which the desorptionisotherm approximates the adsorption isotherm.revivificationsee reactivation.service life (servi
40、ce time)the elapsed time until the endpoint is reached in an adsorption process.service timesee service life.sorptiona process in which molecules of a fluid are taken upby absorption or adsorption, or both.split feeda liquid-phase adsorption process in which apowdered adsorbent is added to the solut
41、ion to be treated intwo or more steps, with or without intermediate separation ofthe adsorbent.surface area (B.E.T.)the total surface area of a solidcalculated by the B.E.T. (Brunauer, Emmett, Teller) equa-tion, from nitrogen adsorption or desorption data obtainedunder specified conditions.surface a
42、rea distributionthe distribution of surface areaaccording to some parameter such as pores of different sizeor diameter.tamped densitysee density, tamped.threshold concentrationthe minimum concentration atwhich a substance can be detected or recognized by its tasteor odor.uniformity coefficientthe ra
43、tio of the particle diametercorresponding to 60 % finer on the cumulative particle sizedistribution curve to the particle diameter corresponding to10 % finer on the same distribution curve.van der Waals adsorption see physical adsorption.water-extractable materialsubstances dissolved from othersubst
44、ances by water under specified conditions.wettabilitythe rate at which particles can be made wet underspecified conditions.4. Keywordsactivated carbonASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. User
45、s of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every
46、five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technica
47、l committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).D 2652 05a3
