Material characterization and kinetic parameters based thermoluminescence study of Pakistani Onyx pellets

The Material characterization and kinetic parameters based Thermoluminescence (TL) study of virgin and heat treated Pakistani Onyx marble is reported. Pellets of mineral under various heat treatments named as virgin (S1), pre-heated (S2), annealed (S3), heat-treated-slowly-cooled (S4), are prepared. Material characterization is performed using TGA, XRD, SEM-EDX, and ICP-OES techniques. ICP & EDXs shows C, O, Ca as major elements and Al, Mn, Mg, Fe, Si as impurity content. Crystalline nature under heat treatment remains unaffected up to 773 K as indicated by the XRD analysis. TGA shows sample is CaCO3 with no mass loss from 303 to 893 K. XRD and TGA analysis concludes that TL analysis is possible within 303-673 K. After 03 Gy of beta-irradiaton dose, the TL responses are investigated. All samples show a thermally stable peak around 552 +/- 3 K. The kinetic features responsible for TL response are studied using Initial rise (IR) method, Chen Peak Shapes (CPS) analysis and P.N. Keating technique. Kinetic order values vary within 1.75-1.05. The activation energy ranges from 0.88 to 1.33 eV, frequency factor appears within 106-1010 s-1. Calculated parameters are validated by comparing MATLAB generated synthetic curves with experimental results. CPS and IR based synthetic curves are in good agreement with the experimental curves. Heat treated Sample S4 shows enhanced TL response as compared to other samples.

Automated summary

The study focused on the material characterization and kinetic parameters of Pakistani Onyx marble using Thermoluminescence, demonstrating that heat treated Sample S4 showed enhanced TL response compared to other samples.