ASTM_D_7626_-_10.pdf

Designation:D762610Standard Test Methods forDetermining the Organic Treat Loading of OrganophilicClay1This standard is issued under the fixed designation D7626;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 standard covers two index test methods that can beused in the evaluation of the amount of organic compoundchemically bonded to the base clay portion of a representativesample of organophilic clay.1.2 The values stated in SI units are to be regarded as thestandard.No other units of measurement are included in thisstandard.1.3 All observed and calculated values shall conform to theguidelines for significant digits and rounding established inPractice D6026.1.3.1 The procedures used to specify how data are collected/recorded or calculated in this standard are regarded as theindustry standard.In addition,they are representative of thesignificant digits that generally should be retained.The proce-dures used do not consider material variation,purpose forobtaining the data,special purpose studies,or any consider-ations for the users objectives;and it is common practice toincrease or reduce significant digits of the reported data to becommensurate with these considerations.It is beyond the scopeof this standard to consider significant digits used in analysismethods for engineering design.1.4 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 and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D653 Terminology Relating to Soil,Rock,and ContainedFluidsD3740 Practice for Minimum Requirements for AgenciesEngaged in Testing and/or Inspection of Soil and Rock asUsed in Engineering Design and ConstructionD4753 Guide for Evaluating,Selecting,and Specifying Bal-ances and Standard Masses for Use in Soil,Rock,andConstruction Materials TestingD6026 Practice for Using Significant Digits in GeotechnicalDataE145 Specification for Gravity-Convection and Forced-Ventilation Ovens3.Terminology3.1 DefinitionsFor common definitions of terms in thisstandard,refer to Terminology D653.3.2 Definitions of Terms Specific to This Standard:3.2.1 base clay,nan untreated naturally occurring clay(e.g.,bentonite,kaolinite).3.2.2 organic treat loading,nthe amount of organic com-pound chemically bonded to the base clay portion of anorganophilic clay.3.2.3 organophilic,adjhaving a strong affinity for oil andother insoluble organic compounds.3.2.4 organophilic clay,na manufactured oleophilic ma-terial consisting of base clay to which an organic compoundhas been chemically bonded to the clay surface.4.Summary of Test Methods4.1 Test Method AMoisture content is determined bydrying an organophilic clay specimen at 160 C in an oven ormuffle furnace.The moisture content is expressed as a percent-age of the as-received mass.The ash content of the organo-philic clay specimen is determined by igniting the driedspecimen from the moisture content determination in a mufflefurnace at 750 C.4.2 Test Method BAn organophilic clay specimen isheated at a controlled rate in a thermal gravimetric analyzer.Percent moisture content and ash are taken from thermalgravimetric analyzer report.4.3 Some volatile structural matter within the base clay willbe lost during the last stage of heating.Organic treat loading isdetermined on a dry weight basis by a calculation that accounts1These test methods are under the jurisdiction ofASTM Committee D18 on Soiland Rock and are the direct responsibility of Subcommittee D18.21 on Groundwaterand Vadose Zone Investigations.Current edition approved May 1,2010.Published June 2010.DOI:10.1520/D7626-10.2For 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.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 for the moisture content,ash,and a nominal percent of volatilestructural matter within the base clay.NOTE1The supplier of the organophilic clay must be able to verifywith historical data the nominal percent mass of the base clay(on a dryweight basis)remaining after similar heating.This value is typically in therange of 94 to 96%.5.Significance and Use5.1 This standard test method is intended as an index test todetermine the organic treat loading of organophilic clay.Thisstandard test method can be used for manufacturing qualitycontrol and construction quality assurance material evaluation.5.2 The percent organic treat loading of organo