Distinguishing of carbons and oxidation behaviour (Part 1): Exploring model-free kinetics and RAMAN spectroscopy as a synergistic approach for evaluating carbon-bonded-refractories

Abstract

A rapid synergetic profiling approach to determining oxidation behaviour and distinguishing of carbons within a refractory composite was explored for steel end user application. The efficacy for both Raman spectroscopy and model free kinetics were studied and proved successful for adoption as routine techniques. With the model free approach, the complex reaction steps were profiled as a multi-step reaction with series of activation energy ranging from 230 KJ/Mol to 150 KJ/Mol. The complex oxidation behaviour was supported by high temperature Raman spectroscopy which corroborated the pore closure mechanism that plays a critical role in modulating reaction intensity. Raman tracked oxidation via its effect on the crystallite sizes of resin (∼ 5.5 nm to 8.5 nm) and intensity peak ratio of D to G peak within some limitations that are discussed in the study. Lastly, an empirical prediction of isothermal experiment from non-isothermal kinetics was validated and considered useful for determining the life of carbon especially in cases where under performance was suspected due to improper preheating by the end-user.

Keywords

• Model free kinetics
• Carbon bonded refractory
• Submerged Entry Nozzle
• Raman Spectroscopy
• Oxidation