Thermogravimetric analysis of pigments and fillers for papermaking Toshiharu Enomae Graduate School of Agricultural and Life Sciences Contact e-mail address: enomae@psl.fp.a.u-tokyo.ac.jp A2 350 450 A2 350 ISO 1762:2001, Paper, board and pulps Determination of residue (ash) on ignition at 525 525 580 JIS P 8251:2002 525 575 25 525 1000 Abstract Thermogravimetric analysis was applied to several kinds of pigments and fillers for papermaking to examine exact temperatures from which mass reduction commences. Clay and talc began to reduce mass from about 350 C and 450 C, respectively. Clay contained in coated paper began to reduce mass from about 350 C. Therefore, Other fillers and pigments (than calcium carbonate) such as clay and titanium dioxide are also unaffected by ashing at 525 C. stated in ISO 1762:2001, Paper, board and pulps - Determination of residue (ash) on ignition at 525 C was found to be apparently wrong. Calcium carbonate began to reduce mass from about 580 C, suggesting no decomposition at 525 C specified in JIS P 8251:2002. The result also suggests no decomposition even at the ashing temperature 575 C specified in the previous edition of ISO 1762. However, the standard tolerates an accuracy of 25 C due to technical difficulty in temperature control of muffle furnaces. So, it is appropriate that the ashing temperature was lowered from 575 to 525 C in the revision. There was no mass reduction 1
for titanium dioxide up to 1000 C. Keywords : ash, clay, calcium carbonate, talc, thermogravimetric analysis, titanium dioxide 1 2 JIS JIS 14 12 2 JIS JIS P 8251:2002 525 JIS P 8252:2002 900 JIS P 8003 JIS P 8128 JIS 2 JIS ISO 1762:2001, Paper, board and pulps Determination of residue (ash) on ignition at 525 ISO 2144:1997, Paper, board and pulps Determination of residue (ash) on ignition at 900 JIS P 8251 ISO 1762 1 Scope In samples containing calcium carbonate, there is practically no decomposition of carbonate by ashing at 525. Other fillers and pigments such as clay and titanium dioxide are also unaffected by ashing at 525. 525 1) 450 500 525 5 % ISO 100 350 0.8 600 mg 10 /min ISO 1762 2001 2) 525 575 525 575 1 5.7 525 575 ISO 2 2.1 1 2
3 1 2 1 2 1 9 A2 ISO 1 t 1 13 mm 1 5 mm 2.2 TGD-9600 1500 1 0.1 ml 20 40 mg 1 20.9 41.4 mg 200 ml/min 15 100 5 /min 1000 800 1 2.3 X X MESA-500 X 50 kv 92 500 µa 50 s 5 mm 2.4 X A2 X X RINT-2000 40 kv 40 µa Cu-Kα 3 3.1 100 15 0.5 % 1 100 15 350 480 650 525 10.2 11.0 % 800 900 12.3 12.8 100 300 700 Al 2 Si 2 O 5 (OH) 4 3) 2 X Al Si Ti Fe TiO 2 3
2 % 3) 13.9 X 2.7 kev X (Rh) X 3 1000 1000 2.5 % Mg 3 Si 4 O 10 (OH) 2 450 660 chlorite (Mg, Fe) 4 Al 4 Si 2 O 10 (OH) 8 Dolomite CaMg(CO 3 ) 2 4) 4 X Ca Fe 850 525 5 A2 580 760 820 40 46 44.0 % JIS P 8251:2002 525 JIS P 8252:2002 900 A2 100 220 350 600 740 A2 525 575 900 28.1 27.7 14.0 % 6 X 3 7 A2 X 4 A2 350 450 A2 350 ISO 1762:2001, Paper, board and pulps Determination of residue (ash) on ignition at 525 525 580 JIS P 8251:2002 525 575 25 525 1000 4
1) Julia Papp: Svensk Papperstidning nr 17 487 (1980) 2) Söderhjelm, L. and Tehomaa, M.: TAPPI J. 84(5) 57(2001) 3) Sennett, P. : Pigments for paper, Tappi Press, Atlanta, Georgia, USA, 1997, 55-88 4) Trivede, N.C.: Pigments for paper, Tappi Press, Atlanta, Georgia, USA, 1997, 199-214 5
Table 1 Pigments and fillers subjected to thermogravimetric analysis Pigment or Filler Manufacturer - Product Description ISO Brightness Sample mass, mg A-1 78.6 20.9 Clay B-1 71.0 36.0 B-2 78.8 36.0 Calcium carbonate Titanium oxide C-1 Precipitated CC, Calcite 94.5 20.9 D-1 Ground CC, Calcite 91.3 41.4 E-1 Precipitated CC, Aragonite 95.2 21.8 F-1 93.5 30.4 G-1 93.9 34.3 Talc H-1 80.8 23.8 Coated paper I-1 A2-grade coated paper 32.5 6
5 0 Mass change, % -5-10 -15 A-1 B-1 B-2 0 100 200 300 400 500 600 700 800 900 1000 Temperature, Fig.1 Thermogravimetric curves of clay 7
70 60 Si A-1 B-1 B-2 50 Ti Fe X-ray count, cps 40 30 Al 20 10 K Ca Ti Fe 0 1 3 5 7 Energy, kev Fig.2 X-ray fluorescence spectra of clay 8
5 0 Mass change, % -5-10 -15 F-1 G-1 H-1 0 100 200 300 400 500 600 700 800 900 1000 Temperature, Fig.3 Thermogravimetric curves of titanium oxide (F-1 and G-1) and talc (H-1) 9
350 300 Ti F-1 G-1 H-1 250 X-ray count, cps 200 150 100 50 Al Mg Si Ca Ca Ti Fe Fe 0 1 3 5 7 Energy, kev Fig.4 X-ray fluorescence spectra of titanium oxide (F-1 and G-1) and talc (H-1) 10
Mass change, % 10 0-10 -20-30 -40-50 -60-70 -80-90 -100 C-1 D-1 E-1 I-1 0 100 200 300 400 500 600 700 800 900 1000 Temperature, Fig.5 Thermogravimetric curves of calcium carbonate and A2-grade coated paper 11
350 300 250 Ca C-1 D-1 E-1 X-ray count, cps 200 150 100 Ca 50 Ti 0 1 3 5 7 Energy, kev Fig.6 X-ray fluorescence spectra of calcium carbonate 12
K C: Calcium carbonate (Calcite) K: Clay (Kaolinite) X-ray counts K C Cellulose C C C C 10 15 20 25 30 35 40 2 θ, degree Fig.7 X-ray diffraction pattern of A2-grade coated paper 13