Effect of pyrochemical waste loading on the heat capacity of Sr(PO)Cl and its glass-bonded composites measured by drop calorimetry.

Maji, Binoy; Jena, Hrudananda; Krishnaiah, M.; Asuvathraman, R.

Strontium chloroapatite (SrApCl) and its borosilicate glass (BSG)-bonded composites loaded with simulated pyrochemical chloride waste (w) compositions were prepared by solid-state reaction route. The products were characterized by powder XRD. Enthalpy increments of the composites were measured by drop calorimetric method at the temperature range of 373-773 K using a homebuilt calorimeter. Heat capacity ( C), entropy ( S) and Gibbs energy functions ( G) in the temperature range of 298-773 K of the above-synthesized composites have been evaluated from the enthalpy increments data by using least-squares fitting. C values found to be in the range of 0.596-0.751, 0.530-0.724, 0.570-0.938, 0.598-0.981 and 0.850-1.097 J K g for SrApCl, SrApCl-10w, SrApCl-20BSG, SrApCl-10w20BSG and BSG, respectively, at the temperatures ranging from 298 to 773 K.

HAZARDOUS wastes; STRONTIUM chloride; THERMAL properties; GLASS composites; BOROSILICATES; X-ray powder diffraction; SOLID state chemistry; GIBBS' free energy

Journal of Thermal Analysis & Calorimetry, 2016, Vol 124, Issue 2, p857

1388-6150

Academic Journal

10.1007/s10973-015-5230-8