Quantitative powder diffraction analyses of cements

Transcription

1 Quantitative powder diffraction analyses of cements Miguel A. G. Aranda Departamento de Química Inorgánica, Universidad de Málaga, Spain

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3 Outline: QPA of cements 1. Introduction: the uses of powder diffraction 2. Introduction: synchrotron radiation 3. Analytical method validation 4. Polymorph determination 5. Portland clinkers and cements 6. In-situ study of belite clinkering 7. Conclusions

4 Introduction: XRPD applications # 1 Identification of crystalline compounds (using the PDF database). (Based on I hkl and d hkl ) # 2 Determination of the unit cell parameters. (Based on d hkl ) # 3 Determination of the crystal structure (atomic parameters). (Based on I hkl and d hkl ) # 4 Quantitative phase analysis (sample purity). (Based on I hkl ) # 5 Determination of the microstructure of the phase. (Based on the shape- FWHM of the I hkl ) (average microparticle size and shape, microstrains, residual stress, etc.) # 6 XRPD can be coupled to thermal variation (thermodiffractometry): Uses for: phase transitions, chemical reactions, melting/crystallization, thermal expansion, # 7,8,9, XRPD coupled to pressure, chemical gradient, magnetic fields, ; and combinations: Uses for: phase transitions, equation of state determination, reactivity, stability,

5 # 1 Identification of crystalline compounds CaSO 4. 2H 2 O Chalk phase identification CaCO 3 Pdf identification

6 # 1 Identification of crystalline mixtures Forensic Science Laboratory of Stuttgart, Germany

7 # 2 Determination of the unit cell parameters. Ca 3-x Mg x SiO 5, main cement phase, x=0.00, 0.02, 0.04, 0.06, 0.08 and The figure shows the evolution in the peak positions, consequence of the evolution of the unit cell parameters. Important for reactivity (water hydration / hardening). 0Mg 02Mg 04Mg 06Mg I (u.a) 08Mg 1Mg

8 # 3 Determination of the crystal structure (atomic parameters)

9 # 4 Quantitative phase analysis (sample purity) XRPD of a pure phase XRPD of a pure phase XRPD of a mixture Elemental analysis XRPD of a mixture XRF, the same XRPD of a pure phase Reaction of MgO-Al 2 O 3 followed by XRPD

10 # 4 Quantitative phase analysis (sample purity)

11 # 5 Determination of the microstructure of the phase Sources of peak broadening Instrumental Broadening Microstructural features Finite Crystallite Size 2 θ (º) FWHM α cos -1 θ size < 0.2 μm (if isotropic) Lattice Strain (microstrain) A antiphase domain B interstitial atom G, K grain boundary L vacancy S substitutional impurity/doping S interstitial impurity P, Z stacking faults dislocations Extended Defects FWHM α tan θ (if isotropic) fluctuations in cell parameters Anisotropic broadening Antiphase Boundaries, Stacking Faults

12 # 5 Determination of the microstructure of the phase CeO 2 standard; a= (6) Å; GSAS, S/L=H/L=0.012; GU=1.95(-); GW= 2.31(2); LX=0.90(2); LY=2.56(4); Rwp=4.55% Parameter Value Error A E-5 B E E R SD N P E-5 14 < CeO 2 nano; a= (9) Å; GSAS, S/L=H/L=0.012; GU=1.95(-); GW= 2.73(-); LX=24.90(3); LY=32.63(6); Rwp=5.9% ( nano - std ) cos D V = 269 Å ó 27(1) nm str = 0.037(2)% sen

13 # 6 XRPD can be coupled to thermal variation (thermodiffractometry) Top: Experimental setup for high-resolution SXRP-thermodiffraction using a hot-air blower at ID31 diffractometer of ESRF. Bottom right: Selected HT-SXRPD patterns for La (Ge 6 O 24 )O 2.62 showing a triclinic-tohexagonal phase transition. Bottom left: Variation of the unit cell volume 636 (b) (a) 632 V/Å T/K /º

14 # 7 In-situ chemical reactivity study (hydration of a cement) Image plate detector: two data collection strategies Translating mode 2D single pattern Integration Fit2D Slit Slit Slit Slit ~2 mm ~ 5 min time resolution Sample X-Rays ~ 5 min/pattern X-Rays

15 Outline: QPA of cements 1. Introduction: the uses of powder diffraction 2. Introduction: synchrotron radiation 3. Analytical method validation 4. Polymorph determination 5. Portland clinkers and cements 6. In-situ study of belite clinkering 7. Conclusions

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17 Bending magnet Insertion devices: undulators & wigglers

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21 Advantages of synchrotron radiation 1. The high resolution decreases the peak overlapping 2. In transmission, a large amount of sample is tested ( =2 mm) 3. The absorption and microabsorption problems are minimal 4. Preferred orientation is almost absent 5. Very high intensities (very short counting times!) Disadvantages of synchrotron radiation vs. laboratory data The patterns are much more expensive A compromise in some cases: Strictly monochromatic X-ray laboratory data (CuK 1 )

22 ) CaSO4 2H 2H2O 2O C4AF CaSO4 ½H 2O C3S CaSO4 2H 2 O C3A C3A C4AF CaSO4 ½H 2 O C3S Two patterns of the same artificial cement 1.- High resolution 2.- No preferred orientation 3.- Good s/n ratio (4.- Good particle statistic) Synchrotron pattern capillary Laboratory pattern flat

23 Outline: QPA of cements 1. Introduction: the uses of powder diffraction 2. Introduction: synchrotron radiation 3. Analytical method validation 4. Polymorph determination 5. Portland clinkers and cements 6. In-situ study of belite clinkering 7. Conclusions

24 Ordinary Portland cement, OPC Tricalcium silicate, Ca 3 SiO 5, C 3 S, alite ~60-70 % Dicalcium silicate, Ca 2 SiO 4, C 2 S, belite ~15-25 % Grey clinker Tricalcium aluminate, Ca 3 Al 2 O 6, C 3 A ~5-10 % Tetracalcium ferroaluminate, Ca 2 (Al,Fe) 2 O 5, C 4 AF ~10% Minor components: ~1-4 % CaO (free lime) // MgO (periclase) Alkaline sulfates: K 2 SO 4 o K 3 Na(SO 4 ) 2 Set time controller CaSO 4 2H 2 O (gypsum) others, CaSO 4 ½H 2 O (bassanite) CaSO 4 (anhydrite) Additions CaCO 3 (calcite), others SiO 2 (quart) CaMg(CO 3 ) 2 (dolomite)

25 Precision and accuracy in quantitative phase analysis of Portland cements by using the Rietveld method White clinker (3 phases) Weighed(%) Weighed c (%) C 3 S C 2 S C 3 A Gray clinker (4 phases) Weighed(%) Weighed c (%) C 3 S C 2 S C 3 A C 4 AF Gray cement (6 phases) Weighed(%) Weighed c (%) C3S C2S C3A C 4 AF Gypsum Basanite Gray cement (7 phases) Weighed(%) Weighed c (%) C3S C2S C3A C4AF Gypsum Basanite CaCO Weighed c corrected values have been obtained by using synchrotron X-ray patterns of binary mixtures of the give phase plus standard-al 2 O 3

26 Weighed(%) Weighed c (%) SXRPD(%) LXRPD 1 (%) LXRPD 2 (%) C 3 S (5) 78.3(1) 79.0(1) C 2 S (13) 17.3(4) 16.2(4) C 3 A (6) 4.4(1) 4.8(1) Weighed(%) Weighed c (%) SXRPD(%) LXRPD 1 (%) LXRPD 2 (%) C3S (8) 60.5(2) 62.6(1) C2S (12) 22.8(2) 20.0(2) C3A (7) 8.5(1) 9.4(1) C4AF (7) 8.2(2) 8.0(2) Weighed(%) Weighed c (%) SXRPD(%) LXRPD 1 (%) LXRPD 2 (%) C3S (7) 61.1(2) 60.9(2) C2S (10) 17.7(5) 17.2(5) C3A (5) 5.1(1) 5.3(1) C4AF (6) 7.6(1) 8.0(1) Gypsum (6) 3.9(1) 4.1(2) Basanite (6) 4.6(2) 4.5(2)

27 (c) 2 /º I (a.u.) I (a.u.) I (a.u.) CaCO3 C4 AF C2 S C3A C2 S C3 A C3 A C4 AF C4AF C3S C3 A C3S (a) (b) (b) (c) (c) 2 /º CaSO4 2H 2 O CaSO4 ½H 2 O I (a.u.) I (a.u.) I (a.u.) CaCO3 C2 S C3 A C4 AF C2 S C3 A C4 AF C3S (a) (b) (b) (c) Synchrotron powder pattern CaSO4 2H 2H2O 2O Laboratory (CuK 1,2 CaSO4 ½H 2O ) powder pattern

28 Weighed(%) Weighed c (%) SXRPD 1 (%) SXRPD 2 (%) LXRPD 1 (%) LXRPD 2 (%) C3S (6) 63.82(6) 62.7(2) 62.2(2) C2S (11) 9.69(11) 11.5(3) 10.8(3) C3A (5) 5.51(4) 5.1(2) 5.2(1) C4AF (5) 4.88(5) 4.4(2) 5.1(2) Gypsum (7) 5.55(7) 4.9(1) 4.9(2) Basanite (6) 4.85(6) 5.5(2) 5.6(2) CaCO (6) 5.70(6) 5.9(1) 6.2(2) Very high precision with SXRPD. Good accuracy with SXRPD Higher errors with LXRPD of the order of 2% for alite. Relative errors for low-content phases are high (10-20%) (absolute error may be 0.5% for phases at 5% concentrations) De la Torre & Aranda, Accuracy in Rietveld quantitative phase analysis of Portland cements Journal of Applied Crystallography, 2003, 36, pp

29 # 3 commercial samples were also studied: (i) white Portland clinker, (ii) grey Portland clinker (iii) a type-i grey Portland cement

30 Just a brief summary for artificial mixture #2

31 Outline: QPA of cements 1. Introduction: the uses of powder diffraction 2. Introduction: synchrotron radiation 3. Analytical method validation 4. Polymorph determination 5. Portland clinkers and cements 6. In-situ study of belite clinkering 7. Conclusions

32 C 3 S Alite: 7 polymorphs with temperature 620ºC 920ºC 980ºC 990ºC 1060ºC 1070ºC T 1 T 2 T 3 M 1 M 2 M 3 R Parámetros de la celda unidad Polimorfo Grupo espacial Z a (Å) b (Å) c (Å) (º) (º) (º) V/Z (Å 3 ) T (ºC)/ Estabilizador T 1 P1 a /- T 2 P1 b /- T 3 P1 c /0.53%MgO + 0.9%Al 2 O 3 M 1 Pc d /Al+Fe+Mg+S M 3 Cm e /1.24%MgO +0.45%Al 2 O 3 R R3m f /Ca 2.98 Si 0.98 Al 0.04 O 5 (a) Golovastikov y col., 1975; (b) Peterson y col., 2004; (c) De la Torre y col. 2008; (d) De Noirfontaine y col., 2006; (e) De la Torre y col., 2002; (f) Nishi y Takéuchi, 1984.

33 Monoclínico M 3 M 3 T 3 C 3 SAlite T 1

34 C 2 S belite 5 polymorphs on heating <500 ºC ºC 690 ºC ' L 1160 ºC ' H 1425 ºC Grupo Parámetros de la celda unidad Polimorfo z V / Å 3 Ref. bibl. espacial a / Å b / Å c / Å / º P6 3 /mmc (a) ' H Pnma (b) ' L Pna (b) P2 1 /n (a) Pbnm (c) (a) Mumme y col., 1995; (b) Mumme y col., 1996; (c) Udagawa y col., 1980.

35 -C 2 S -C 2 S

36 Na 2 O / % C 3 A aluminate has 4 pseudo-polymorphs Polimorfo Grupo espacial Z Parámetros de la celda unidad a / Å b / Å c / Å / º V / Å CI Pa (a) CII P (b) O Pbca (b) M P2 1 /a (b) (a) Mondal y Jeffery, 1975; (b) Takeuchi y col., Ref. bibl. Foreign ions C 3 A in commercial clinkers

37 C 3 A (a) C 3 A Cubic-I (b) C 3 A Cubic-II (c) C 3 A orthorhombic (d) C 3 A monoclinic Very high alkaline contents

38 C 4 AF It is not present in white clinkers/cements Solid solution: Ca 2 Al x Fe 2-x O 5 0<x<0.60 P cmn 0.60<x<1.33 I bm2 (in OPC, the Fe/Al ratio, x=1) other possible phases: C 2 F-C 6 AF 2 -C 4 AF-C 6 A 2 F- C 2 A Parámetros de la celda unidad Grupo espacial Z V / Å 3 x Ref. bibl. a / Å b / Å c / Å Pcmn (a) Ibm (b) (a) Colville, 1970; (b) Colville y Géller, 1971.

39 Fe/Al ratio fixed (x=1) but the distribution Td / Oh sites changes fe00 fe50 fe100 C 4 AF Fe/Al ratio change

40 I (u.a.) C2 S C2 S C3 A 2 /º I (u.a.) CaCO3 Arcanita Arcanita Arcanita C3 A C3 A C3 A 2 /º I (u.a.) C2 S C2 S White clinker C 3 S C 2 S C 3 A Selective dissolution Aluminate enriched fraction Selective dissolution Silicate enriched fraction 2 /º

41 K2 SO 4 C2S C3S C2S C3S C3S C4AF C4AF C4AF C4AF C3S C3A C4 AF C4 AF C3S Grey Portland clinker Clinker F6 Provided sample D5000 data Clinker F6 Aluminates fraction C2S C2S C3S C3S Salicylic C3 A C3S C3S C4 AF C3A Preliminary study C 3 S C 2 S, C 4 AF C 3 A Selective dissolution Aluminate rich fraction Selective dissolution Silicate rich fraction Clinker F6 Silicates fraction

42 Selective dissolution of belite clinkers Polymorph determination: Silicate enriched residue B_ref Silicate residue β-c2 S α -C S H 2 β-c2 S α -C S H 2 α -C S H 2 β-c2 S β-c2 S α -C S H 2 β-c2 S β-c2 S β-c2s β-c2 S β-c2 S α -C S H 2 β-c2 S C3 A C4 AF β-c2 S β-c2s C3S α -C S H 2 β-c2 S B_1.5Na β-c2 S α-c2 S C3 A C4 AF α -C β-c2s S H 2 α-c2 S Silicate residue β-c2 S β-c2 S α -C S H 2 α-c2 S C3S α -C S α-c S H 2 2

43 Selective dissolution of belite clinkers Polymorph determination: aluminate enriched residue B_1.5Na C3Aort C3Aort C4AF C4AF C4 AF C4AF C3 A ort C3Aort β-c2s C3S α-c2s C3S β-c2s C3S α H-C2S C3 A C4 AF C3S α-c2s B_ref α H-C2S C 3S C3S β-c2s α H-C2S C3A C 4AF β-c2s C3S β-c2s β-c2s C 3S α H-C2S β-c2s C 3S Aluminate residue Aluminate residue C 3A cub C 3A cub C 3A cub C 3A cub C 4AF C 3A cub C 4AF C 4AF C 4AF C 4AF C 3A cub C 4AF Morsli et al. Quantitative Phase Analysis of Laboratory-Active Belite Clinkers by Synchrotron Powder Diffraction Journal American Ceramic Society, 2007, 90,

44 Synchrotron powder diff. data =0.44 Å I (a.u.) C3S C3S C3S C3S Polymorph determination: C 3 S, monoclinic, C m C 2 S, monoclinic, P2 1 /n C3S NKS C2S NKS C2S C3A C4AF C4AF C2S C3S C2S C2S C C 4 AF, orthorhombic, Ibm2 C 3 A, cubic, Pa-3 (no orth.) Aftitalite, NaK 3 (SO 4 ) 2, trigonal P -3m º 10.5 C, cubic, F m-3m De la Torre et al., Full Phase Analysis of Portland Clinker by Penetrating Synchrotron Powder Diffraction Analytical Chemistry, 2001, 73, pp

45 Outline: QPA of cements 1. Introduction: the uses of powder diffraction 2. Introduction: synchrotron radiation 3. Analytical method validation 4. Polymorph determination 5. Portland clinkers and cements 6. In-situ study of belite clinkering 7. Conclusions

46 Grey clinker 2 /º Free lime C2 S aphtitalite C2 S I (u.a.) C3 A C4 AF C4 AF CaOfree I (u.a.) 3-4 hours 2 /º aphtitalite C2 S C2 S C3 A C4 AF C4 AF CaOfree

47 Grey clinker I (u.a.) Cement (a) # 1 C 3 S C 3 S C 3 S C 3 A * C 3 S phases Cement_1 Cement_2 Cement_3 C 3 S C 2 S C 2 S C 4 AF C 4 AF C 3 S 73.7(1) 69.8(2) 73.4(3) C 2 S 8.1(3) 10.2(5) 12.5(7) C 4 AF 5.5(2) 12.4(3) 11.9(4) I (u.a.) Cement (b) # 2 C 3 S C 3 S C 3 S * I (u.a.) C 3 S C 3 S C 3 S C 2 S C 2 S C 3 S C 3 A 12.3(1) 4.9(2) 1.3(3) Aphita. 0.5(1) 2.7(2) - C 3 S C 2 S C 2 S C 3 A C 4 AF C 4 AF CaO (1) Cement (c) #3 * C 3 S C 3 S C 3 A C 4 AF C 4 AF 2 /º

48 Portland cement Set up regulator I (u.a.) Dehydration processes in cement mill(s) 2 /º I (u.a.) gypsum C 4 AF Bassanite C 3 S 2 /º

49 2 /º Additions Other components 2 /º I (u.a.) C2 S I (u.a.) CaCO3 C3 A C4 AF CaCO3 Portland cement

50 Alternative fuel study C 3 S Phase CEM-1 CEM-2 Ca 3 SiO 5 (C 3 S) 62.4 ± ± 0.5 Ca 2 SiO 4 (C 2 S) 8.5 ± ± 0.5 C 3 S C 3 S Ca 3 Al 2 O 6 (C 3 A) 5.3 ± ± 0.2 Ca 2 AlFeO 5 (C 4 AF) 5.7 ± ± 0.3 basanita C 3 S CaSO 4 1/2H 2 O (basanite) 3.8 ± ± 0.2 CaSO 4 (anhidrite) 1.3 ± ± 0.2 SiO 2 (quartz) 0.8 ± ± 0.1* C 3 S C 2 S ZnO C 3 A C 4 AF ZnO C 3 S calcita CaCO 3 (calcite) 10.8 ± ± 0.2 CaMg(CO 3 ) 2 (dolomite) 0.3 ± 0.2* 1.0 ± 0.2 ZnO (zincite) 1.1 ±

51 Environmental applications (particles in suspension) Care during sample collection I (u.a.) C3S kiln Calcite quarry (fingerprint/dna) 2 /º

52 On-line analyses C3S-Alita 62 % 4 minutes! º/2 Cuarzo 0,7 % Yeso 1,2 % Arcanita 1,8 % Basanita 2,5 % Calcita 2,9 % C3A-Aluminato tricálcico cúb. 4,8 % C2S-Belita 13,2 % C4AF-Brow nmillerita 11,1 %

53 Outline: QPA of cements 1. Introduction: the uses of powder diffraction 2. Introduction: synchrotron radiation 3. Analytical method validation 4. Polymorph determination 5. Portland clinkers and cements 6. In-situ study of belite clinkering 7. Conclusions

54 6. IN-SITU X-ray synchrotron study Clinkerization process for an ordinary Portland Clinker CO 2 Proporción Portions by de weight Compuestos CaCO 3 -Cuarzo -Quartz Arcill Clays a Fe 2 O 3 CaO Belita C 2 S C 2 S -cuarzo Alita C 3 S C 3 S C C A 3 A 7 C líquido 4 AF liquid C 4 AF 4 AF T RT(ºC) Temperature (ºC) cooling ºC Decarbonation (CO 2 ) ºC free lime, Al & Fe rich phases and silicates ºC Quenching liquid phase + silicates Phase stabilisation + subcooled liquid

55 Why an in-situ study? Clinkerization process for belite clinkers is not well known Polymorphic transformations at high temperature Liquid appearance temperature(s) Influence of minor elements in these reactions Selected compositions sample K 2 O/% Na 2 O/% B_ref - - Bel_10K Bel_15Na Bel_05K05Na Bel_10S10K Bel_10S05K05Na SO 3 /% Thermal pre-treatment for decarbonation 1 h 5 ºC/min 1000 ºC

56 Thermo-diffractometric data collection Metallic sample holder MgO refractory capillary Pt capillary Ø=0.6 mm Raw mix inside Data collection ESRF (Grenoble) ID31 diffractometer = Å Debye Scherrer configuration Capillaries were spun Angular range o (in 2 ) 15 minutes per run 3 runs for a single pattern Real temperature was checked by Pt peak positions Refractory ceramic adhesive Samples were heated from 900 to 1450ºC

57 Halogens lamps Ceramic holder

58 Reference belite clinker (B_ref) on heating 1055ºC Free lime (CaO ) 9.6(2)wt% (1) Primary formation of C 4 AF ( ) 80 wt % CaO L -C 2 S H -C 2 S C 4 AF C 3 A CS 3 -C 2 S Liquid phase 1240ºC T / ºC Free lime (CaO ) 4.2(1)wt% (3) Formation of C 3 A ( ) (4) Crystal size growth of C 4 AF ( )

59 B_ref on heating (continuing) 1300ºC (5) Melting of C 3 A ( ) & C 4 AF ( ) (6) H -C 2 S( ) + CaO Liquid phase ( ) C 3 S ( ) Free lime (CaO ) 0.0wt% 80 wt % CaO L -C 2 S H -C 2 S C 4 AF C 3 A CS 3 -C 2 S Liquid phase 1350ºC T / ºC (7) H -C 2 S -C 2 S( ) C 3 S ( )

60 Liquid phase (B_ref) on heating C 4 AF C 3 A 1300 ºC 1180 ºC 1055 ºC 920 ºC Melting Formation/sinterization Formation /º C 4 AF/% C 3 A/% 16 8 Nominal composition 17.7(3) 6.2(2) 1180ºC

61 1138 ºC Effects of minor elements, Na, K & S, on heating Active belite clinker 0.5% K 2 O, 0.5% Na 2 O & 1.0% SO 3 C 3 A cubic 1140 ºC Active belite clinker 1.5% Na 2 O Na 2 O stabilizes C 3 A orthorhombic

62 Active belite clinker 1.0% K 2 O (B_10K) on cooling B_1.0K -C 2 S ' H -C 2 S ' L -C 2 S C 3 S C 3 A C 4 AF CaO Liquid phase 1200 ºC (1) (2) 14.0(2) 4.6(1) ºC 72.7(1) (2) ºC 72.9(1) (2) ºC 72.4(1) (2) ºC (2) (2) 3.3(2) 5.6(3) ºC (1) (2) 3.3(2) 6.2(3) ºC (1) 10.3(2) 9.5(2) 3.5(1) 6.5(3) RT 1100ºC 1200ºC 1250ºC 1300ºC 1350ºC 1400ºC cooling /º

63 Hydration of cements would need another full lecture Both, data collection and data analysis is more complex!

64 Outline: QPA of cements 1. Introduction: the uses of powder diffraction 2. Introduction: synchrotron radiation 3. Analytical method validation 4. Polymorph determination 5. Portland clinkers and cements 6. In-situ study of belite clinkering 7. Conclusions

65 Conclusions Rietveld quantitative phase analysis gives useful information in cement chemistry. (The answer will depend on the problem) It is useful for both: i) Analyzing commercial samples & ii) The study (and optimization) of laboratory cementitious materials

66 Acknowledgements Many thanks to María de los Ángeles Gómez de la Torre Co-worker at Universidad de Málaga Thanks to ESRF for providing the X-ray synchrotron beam time Thanks to PANalytical for some specific data collection Finally, to all of you for your attention!!

67 Quantitative powder diffraction analyses of cements Miguel A. G. Aranda Departamento de Química Inorgánica, Universidad de Málaga, Spain

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