An Investigation of New Phase Diagram of Ag2SO4 - CaSO4

Authors: Ravi V. Joat, Pravin S. Bodke, Shradha S. Binani, S. S. Wasnik

Abstract:

A phase diagram of the Ag₂SO₄ - CaSO₄ (Silver sulphate – Calcium Sulphate) binaries system using conductivity, XRD (X-Ray Diffraction Technique) and DTA (Differential Thermal Analysis) data is constructed. The eutectic reaction (liquid -» a-Ag₂SO₄ + CaSO₄) is observed at 10 mole% CaSO₄ and 645°C. Room temperature solid solubility limit up to 5.27 mole % of Ca ²⁺ in Ag₂SO₄ is set using X-ray powder diffraction and scanning electron microscopy results. All compositions beyond this limit are two-phase mixtures below and above the transition temperature (≈ 416°C). The bulk conductivity, obtained following complex impedance spectroscopy, is found decreasing with increase in CaSO₄ content. Amongst other binary compositions, the 80AgSO₄-20CaSO₄ gave improved sinterability/packing density.

Keywords: Ag2SO4-CaSO4 (Silver sulphate–Calcium Sulphate) binaries system, XRD (X-Ray Diffraction Technique) and DTA (Differential Thermal Analysis).

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1094665

References:

[1] B. Heed, A. Lunden and K. Schroeder, 10th Intersoc Energy Conversion Engg. Conf,Aug(1975)p.613.
[2] K, Singh and S. S. Bhoga, Bull Mater. Sci., 22 (1999) 71.
[3] Q. G. Liu and W. L. Worrel, U.S. Pat, 303-320 (1981) 17.
[4] W. L. Worrel and Q. G. Liu, J. Electroanal. Chem., 168 (1984) 355.
[5] C. M. Mari," M. Beghi and S. Pizrini, Sensors and Actuators B, 2 (1990) 51.
[6] H. Flood and N. Boye, Z. Electrochem., 66 (1962) 184.
[7] D. M. Haaland, J. Electrochem. Soc., 127 (1980) 796.
[8] Y. Saito, T. Maruyama, Y. Matsumoto, K. Kobayashi and Y. Yan, Solid State Ionics, 14(1984)273.
[9] M. Kumari, E.A. Secco, Can. J. Chem. 56 (1978) 2616.
[10] Y. Saito, T. Maruyama, Y. Matsumoto, K. Kobayashi, Thermochim Acta, 53 (1982) 289.
[11] A. Kvist, Acta Universitat, Gothoburgensis 2 (1967).
[12] Q. Liu, X. Sun and W. Wu, Solid State Ionics, 40-41 (1990) 465.
[13] K. Singh, S. M. Pande, S. W. Anwane and S. S. Bhoga, J. Appl. Phys. A, 66(1998) 205.
[14] R. Nacken, Neues Jahrb. Mineral. Geol, 24 (1907) 55.
[15] T. Takahashi, E. Namura and O. Yamamoto, J. Appl. Electrochem, 2 (1972) 51.
[16] H. A. Oye, Thesis (Technical University of Norway, Trondheim) 1963.
[17] M. S. Kumari and E. A. Secco, Can. J. Chem. 61 (1983) 2804.
[18] M. S. Kumari and E. A. Secco, Can. J. Chem. 63 (1985) 324.
[19] K. Singh and S. S. Bhoga, Appl. Phys. A. 67 (1998) 475.
[20] K Singh and S. S. Bhoga, Proc. 4th National Seminar on Physics and Technology of Sensors, India, (1997) C23-.
[21] K. Singh and S. S. Bhoga, J. Solid State Chem., 97 (1992) 141.
[22] T. S. Irvin and A. R. West, Solid State Ionics. 28 (1988) 214.
[23] H. H. Hoffer, W. Eysel and U. V. Alpen, J. Solid State Chem., 36 (198\1) 365.