1、Designation: C1662 10C1662 17Standard Practice forMeasurement of the Glass Dissolution Rate Using theSingle-Pass Flow-Through Test Method1This standard is issued under the fixed designation C1662; the number immediately following the designation indicates the year oforiginal adoption or, in the case
2、 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 practice describes a single-pass flow-through (SPFT) test method that can be used to me
3、asure the dissolution rate ofa homogeneous silicate glass, including nuclear waste glasses, in various test solutions at temperatures less than 100C. Tests maybe conducted under conditions in which the effects from dissolved species on the dissolution rate are minimized to measure theforward dissolu
4、tion rate at specific values of temperature and pH, or to measure the dependence of the dissolution rate on theconcentrations of various solute species.1.2 Tests are conducted by pumping solutions in either a continuous or pulsed flow mode through a reaction cell that containsthe test specimen. Test
5、s must be conducted at several solution flow rates to evaluate the effect of the flow rate on the glassdissolution rate.1.3 This practice excludes static test methods in which flow is simulated by manually removing solution from the reaction celland replacing it with fresh solution.1.4 Tests may be
6、conducted with demineralized water, chemical solutions (such as pH buffer solutions, simulated groundwatersolutions, and brines), or actual groundwater.1.5 Tests may be conducted with crushed glass of a known size fraction or monolithic specimens having known geometricsurface area. The reacted solid
7、s may be examined to provide additional information regarding the behavior of the material in thetest and the reaction mechanism.1.6 Tests may be conducted with glasses containing radionuclides. However, this test method does not address safety issues forradioactive samples.1.7 Data from these tests
8、 can be used to determine the values of kinetic model parameters needed to calculate the glass corrosionbehavior in a disposal system over long periods (for example, see Practice C1174).1.8 This practice must be performed in accordance with all quality assurance requirements for acceptance of the da
9、ta.1.9 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.1.10 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establ
10、ish appropriate safety safety, health, and healthenvironmental practices and determine theapplicability of regulatory limitations prior to use.1.11 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Prin
11、ciples for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2C92 Test Methods for Sieve Analysis and Water Content of Refractory MaterialsC169C162 Test Me
12、thods for Chemical Analysis of Soda-Lime and Borosilicate GlassTerminology of Glass and Glass ProductsC429 Test Method for Sieve Analysis of Raw Materials for Glass Manufacture1 This practice is under the jurisdiction of ASTM Committee C26 on Nuclear Fuel Cycle and is the direct responsibility of Su
13、bcommittee C26.13 on Spent Fuel and HighLevel Waste.Current edition approved June 1, 2010Nov. 15, 2017. Published July 2010December 2017. Originally approved in 2007. Last previous edition approved in 20072010 asC1662 - 07.C1662 10. DOI: 10.1520/C1662-10.10.1520/C1662-17.2 For referencedASTM standar
14、ds, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This document is not an ASTM standard and is intended only to provide the user of an ASTM
15、 standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published b
16、y ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1C693 Test Method for Density of Glass by BuoyancyC859 Terminology Relating to Nuclear MaterialsC1109 Practice for Analysis of Aqueous Lea
17、chates from Nuclear Waste Materials Using Inductively Coupled Plasma-AtomicEmission SpectroscopyC1174 Practice for Evaluation of the Long-Term Behavior of Materials Used in Engineered Barrier Systems (EBS) forGeological Disposal of High-Level Radioactive WasteC1220 Test Method for Static Leaching of
18、 Monolithic Waste Forms for Disposal of Radioactive WasteC1285 Test Methods for Determining Chemical Durability of Nuclear, Hazardous, and Mixed Waste Glasses and MultiphaseGlass Ceramics: The Product Consistency Test (PCT)C1463 Practices for Dissolving Glass Containing Radioactive and Mixed Waste f
19、or Chemical and Radiochemical AnalysisD1129 Terminology Relating to WaterD1193 Specification for Reagent WaterD1293 Test Methods for pH of WaterE691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method3. Terminology3.1 Please refer to Terminologies C162 and C8
20、59 for additional terminology which may not be listed below.3.2 Definitions:3.1.1 alteration phase, na solid phase formed as a result of corrosion, including phases precipitated from solution, leachedlayers, and phases formed within leached layers.3.1.2 back reaction, nreaction between dissolved com
21、ponents and the glass surface to reform bonds that are broken duringglass dissolution.3.1.3 chemical durability, nthe resistance of a glass to dissolution under particular test conditions.3.1.4 continuous flow, nthe continual replacement of solution in the reaction cell with fresh test solution.3.1.
22、5 control test, ntest conducted without specimen to measure background concentrations in the test solution and frominteractions between test solution and apparatus.3.1.6 crushed glass, nsmall particles of glass produced by mechanically fracturing larger pieces of glass.3.1.7 dissolution, nthe result
23、 of reactions in which chemical bonds are broken and species are released from the glass andbecome dissolved in the test solution.3.2.1 effluent solution, nthe solution exiting the reaction cell.3.2.2 fines, nsmall pieces of glass that adhere to the glass particles prepared for use in the test that
24、are not removed by sieving.3.1.10 forward glass dissolution rate, nthe rate at which glass dissolves into solution at specific values of the temperature andpH in the absence of back reactions.3.1.11 gravimetric, adjmeasured by change in mass.3.2.3 high-purity water, nASTM Type I or Type II water wit
25、h a maximum total matter content including soluble silica of 0.1g/m3 and a minimal electrical resistivity of 16.67 Mcm at 25C (see Specification D1193 and Terminology D1129).3.2.4 influent solution, nthe solution entering the reaction cell.3.1.14 intrinsic rate constant, nthe component of the forwar
26、d rate constant that depends only on the glass composition3.1.15 leached layer, nresidual material at the glass surface from which some or all soluble components have been leached.3.2.5 leaching, nthe preferential loss of soluble components from a material.3.2.6 mesh size fraction, na designation of
27、 the size range of crushed glass given by the combination of the smallest mesh sizethat the glass is passed through (prefixed by a negative sign) and the largest mesh size that it does not pass through (prefixed bya positive sign). For example, the 40 +60 mesh size fraction will pass through a 40 me
28、sh sieve but will not pass through a 60mesh sieve.3.1.18 pulsed flow, nthe replacement of solution in the reaction cell with fresh test solution due to the regular periodic actionof a mechanical pump. Excludes manual replacement of the test solution.3.2.7 reaction cell, nthe container in which the s
29、ample remains during the test.3.2.8 secondary phase, nany phase that is not present in the glass being tested that is formed in solution or on the surface ofthe sample or apparatus by combination of components released from the glass as it dissolved or present in the test solution.3.1.21 single-pass
30、 flow-through test (SPFT), na test in which solution is flushed from the system after contacting the testspecimen and is not recirculated through the reaction cell.3.2.9 steady-state, adjin this standard, the condition in which the concentration of a dissolved glass component remainsconstant due to
31、the opposing effects of solution flow to remove the components from the vicinity of the sample and glassC1662 172dissolution to add components to solution. In the present context, dissolution of the glass may proceed at a steady-state rate thatis fixed by the solution flow rate, temperature, solutio
32、n pH, and other rate-affecting processes.3.1.23 stoichiometric dissolution, nrelease of elements into solution in the same proportion that they are in the glass.3.2.10 test solution, nthe solution entering the reaction cell.4. Summary of Practice4.1 Crushed or monolithic glass specimens having a kno
33、wn surface area are contacted by a solution that continuously flows ata known flow rate and at a constant temperature through a reaction cell that contains the glass sample. The concentration of asoluble glass component (i) in the effluent solution exiting the sample cell is used to calculate the am
34、ount of glass that hasdissolved. The flow rate is determined by dividing the mass of solution that is collected for analysis by the duration over whichit was collected. The dissolution rate of the glass is calculated by using Eq 1:rate5Cii! 2Ci#SFSDfi (1)where Ci(i) is the steady-state concentration
35、 of component i measured in the effluent solution, Ci is the backgroundconcentration of component i in the influent solution measured in a blank test, F is the solution flow rate, S is the initial surfacearea of the glass sample that is exposed to solution, and fi is the mass fraction of component i
36、 in the glass. Several samples of theeffluent solution are collected during the test to determine the steady-state concentrations of dissolved glass components at aparticular solution flow rate. Because the glass dissolution rate will likely be affected by the steady-state concentrations ofdissolved
37、 silica and other solutes, tests must be conducted at several solution flow rates to provide data that can be extrapolatedto zero concentration to determine the forward glass dissolution rate at infinite dilutions.5. Significance and Use5.1 This practice provides a prescriptive description of the de
38、sign of a SPFT test apparatus and identifies aspects of theperformance of SPFT tests and interpretation of test results that must be addressed by the experimenter to provide confidence inthe measured dissolution rate.5.2 The SPFT test method described in this practice can be used to characterize var
39、ious aspects of glass corrosion behavior thatcan be utilized in a mechanistic model for calculating long-term behavior of a nuclear waste glass.5.3 Depending on the values of test parameters that are used, the results of SPFT tests can be used to measure the intrinsicdissolution rate of a glass, the
40、 temperature and pH dependencies of the rate, and the effects of various dissolved species on thedissolution rate.5.4 The reacted sample recovered from a test may be examined with surface analytical techniques, such as scanning electronmicroscopy, to further characterize the corrosion behavior. Such
41、 examinations may provide evidence regarding whether the glassis dissolving stoichiometrically, if particular leached layers and secondary phases were formed on the specimen surface, and soforth. These occurrences may impact the accuracy of the glass dissolution rate that is measured using this meth
42、od. This practicedoes not address the analysis of solid reaction materials.6. Procedure6.1 Fig. 1a shows a block diagram for a generic SPFT test assembly. The components of the system include a solution reservoir,transport lines, a pump, a reaction cell, and a collection bottle. The test solution is
43、 pumped from a reservoir through a reaction cellthat contains the sample by a peristaltic pump or similar device. Depending on the temperature of interest, the reaction cell maybe located in a constant temperature oven or water bath. The leachant in the reservoir can be heated to the test temperatur
44、e in thesame oven. As influent solution is pumped into the reaction cell, an equal volume of effluent solution will be displaced from thereaction cell. The effluent solution is sampled several times during the test for analysis. The mass of effluent that is collected foranalysis and the collection t
45、ime are used to calculate the solution flow rate for that aliquot. Chemical analysis of the effluentsolution is performed to measure the concentration of the components used to calculate the dissolution rate. The concentrationsof several glass components can be tracked to determine whether the glass
46、 is dissolving stoichiometrically. Separate tests areconducted at several flow rates and with several sample surface areas to measure the effect of the solution composition (primarilythe dissolved silica concentration) on the measured glass dissolution rate.6.2 Either column-type or bottle-type reac
47、tion cells can be used; these are shown schematically in Fig. 1. In the column celldesign, the influent solution is pumped (usually upwards) through the crushed glass (or around a monolithic sample). In the bottledesign, the influent solution is pumped into a cell filled with solution and displaces
48、an equal volume of effluent solution.Polyethylene wool or an equivalent material can be used to prevent crushed glass particles from being flushed from the reactioncell during the test, or the effluent solution can be filtered after it is collected.6.3 Crushed glass can be used to provide high surfa
49、ce area samples. Crushed glass is to be prepared following the procedurefor crushed sample preparation in Test Method C1285 (see Section 19 in C1285; see also Test Methods C92 and C429 for sievingC1662 173methods). The surface area of crushed and sieved glass is estimated based on the size fraction that is used in the test. The particlesize of crushed samples must be large enough that the decrease in surface area during the test is less than 15 mass 30 percent. Theinitial surface area can be calculated from the specific surface area and using
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