ASTM_D_7385_-_21.pdf

Designation:D738521Standard Guide forEstimating Carbon Saturation by Temperature Rise UponImmersion1This standard is issued under the fixed designation D7385;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 indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This guide covers the measurement of the temperaturerise resulting from the heat of immersion when a known massof a specified organic liquid is added to a sample of activatedcarbon.If the carbon has been in use as an adsorbent and maytherefore be partially or fully exhausted,its degree of satura-tion may be estimated by comparing its temperature rise withthat of an unused sample of the same activated carbon.1.2 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.3 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2D2652 Terminology Relating to Activated CarbonD2854 Test Method for Apparent Density of ActivatedCarbon3.Terminology3.1 Terms related to this guide are defined in TerminologyD2652.4.Summary of Guide4.1 A measured volume of activated carbon is added to aknown volume of a selected organic liquid in a containerprovided with means to measure the liquid temperature.Theapparatus is sealed after the addition of the carbon and themaximum rise in temperature is recorded.The degree ofsaturation of a used carbon is estimated by comparing itstemperature rise with that of the original unused activatedcarbon of equivalent moisture content,measured under thesame conditions.If no such reference sample is available,acommercial unused activated carbon of the same physical typefrom a reputable manufacturer may be substituted;suchsubstitution should be noted in the report.5.Significance and Use5.1 It is often useful to estimate the degree of saturation,andhence the expected remaining service life,of activated carbonthat has been in use for some time.This guide is applicablewhen such information must be obtained fairly rapidly underfield conditions without access to optimal analytical instru-ments.3The organic liquid used should be of the same organiccomposition as that adsorbed on the carbon sample.6.Apparatus and Materials6.1 ApparatusThe apparatus should consist of a containersuch as a small bottle or flask to accommodate the carbon,theorganic liquid,and a thermometer or thermocouple with arange to allow for a temperature rise of up to about 30 C,graduated in intervals of 0.5 C,with facility to interpolate to60.1 C.A liquid-in-glass thermometer should not use mer-cury because of the greater risk of breakage under fieldconditions.The container should be provided with a rubberstopper or other suitable closure to seal the contents after thecarbon has been added to the organic liquid.Appropriatecontainers include an Erlenmeyer or Florence flask of about125 to 250 mL capacity or a similar-sized narrow-neckedbottle.6.2 MaterialsMany organic liquids that are insoluble inwater but readily soluble in other adsorbates that may already1This guide is under the jurisdiction of ASTM Committee D28 on ActivatedCarbon and is the direct responsibility of Subcommittee D28.04 on Gas PhaseEvaluation Tests.Current edition approved June 1,2021.Published June 2021.Originallyapproved in 2007.Last previous edition approved in 2013 as D7385 13.DOI:10.1520/D7385-21.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3Stone,H.W.and Clinton,R.O.,Ind.Eng.Chem.,Anal.Ed.,Vol 14,1942,p.131.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.1be on the carbon are potentially useful.Special attention needsto be given when choosing the organic liquid.The organicliquid chosen to determine the degree