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TM_D_7442_
_08a
Designation:D744208aStandard Practice forSample Preparation of Fluid Catalytic Cracking Catalystsand Zeolites for Elemental Analysis by Inductively CoupledPlasma Atomic Emission Spectroscopy1This standard is issued under the fixed designation D7442;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.Scope*1.1 This practice covers uniform dissolution techniques forpreparing samples of fluid catalytic cracking catalysts(FCC)and exchanged zeolitic materials for analysis by InductivelyCoupled Plasma Atomic Emission Spectroscopy(ICP-AES).These techniques describe standardized approaches to well-known,widely used laboratory practices of sample preparationutilizing acid digestions and borate salt fusions.This practice isapplicable to fresh and equilibrium FCC catalysts and ex-changed zeolite materials.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 and health practices and determine the applica-bility of regulatory limitations prior to use.2.Terminology2.1 Acronyms:2.1.1 FCCFluid Catalytic Cracking2.1.2 FCCUFluid Catalytic Cracking Unit2.1.3 ICP-AESInductively-CoupledPlasma-AtomicEmission Spectroscopy3.Summary of Practice3.1 Three preparation techniques are presented for convert-ing solid,power samples into clear,dilute acid solutionssuitable for analysis by ICP-AES.The three techniques pre-sented are Perchloric Acid Digestion,Sulfuric Acid Digestion,and Lithium-Borate Fused Dissolution.Other techniques maybe possible;however,these three approaches are established,widely used laboratory techniques for preparing FCC catalystand catalyst-like samples.3.2 Powder samples are heat-treated for 1 to 3 h to removevolatile components prior to further preparation by any of thesethree techniques.3.3 The Perchloric Acid and Sulfuric Acid techniques in-volve dissolving small aliquots of heat-treated sample in therespective acid liquors and diluting the resulting solutions tothe appropriate analytical volume.These techniques requireboiling acid solutions in platinum or polytetrafluoroethylene(PTFE)labware and shall be used in appropriate fume hoods.The PerchloricAcid Digestion shall never be used in a standardfume hood.3.4The Lithium Borate Fused Dissolution technique in-volves dissolving small aliquots of heat-treated sample in amolten flux of lithium metaborate and lithium tetraborate salts,dissolving the resulting flux solution in a dilute nitric acidsolution,and diluting the clear,concentrated specimen solutionto an appropriate analytical volume.This technique must beperformed in an operational fume hood and can be performedmanually or may utilize the advantages of an automated fluxer.The optimal ratio of flux to sample,as well as fusiontemperature needed,will vary depending on sample matrix.4.Significance and Use4.1 The chemical composition of catalyst and catalyst ma-terials is an important indicator of catalyst performance and isa valuable tool for assessing parameters in a FCCU process.This practice will be useful to catalyst manufacturers andpetroleum refiners for quality verification and performanceevaluation,and to environmental authorities at the state andfederal levels for evaluation and verification of various com-pliance programs.2,3,44.2 Catalysts and catalyst type materials are difficult toprepare for analysis by ICP,and although the techniques1This practice is under the jurisdiction of ASTM Committee D32 on Catalystsand is the direct responsibility of Subcommittee D32.03 on Chemical Composition.Current edition approved Sept.1,2008.Published September 2008.Originallyapproved in 2008.Last previous edition approved in 2008 as D744208.DOI:10.1520/D7442-08A.2Dean,John R.,Practical Inductively Coupled Plasma Spectroscopy,JohnWiley,New York,2005.3Gaines,Paul,“ICP Operations,”at B.,“First Aid for a Unique Acid:HF,”Chemical Health andSafety,Vol 5,Sept/Oct 1998,p.25.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 presented in this practice are common,there is wide variationamong laboratories in sample pretreatment and digestionrecipes.This practice is intended to standardize these variablesin order to facilitate the utility of comparative data amongmanufacturers,refiners,and regulatory agencies.5.Apparatus5.1 Muffle Furnaceat 538 to 593C.5.2 Analytical Balance.5.3 Digestion Vesselsplatinum dish or PTFE beaker.5.4 Volumetric FlasksClass A glass,250 mL.5.5 Automated Fusion Machinealternate to manual