Assessment of Cs volatility loss during glass melting adopting microwave and conventional heating

Abstract

In this study, capability of microwave heating has been evaluated to reduce cesium (Cs) evaporation during melting. Glasses of different composition are prepared using microwave (MW) and conventional resistive heating furnaces. Energy-dispersive X-ray spectroscopy (EDX) inductively coupled plasma mass spectrometry (ICP-MS), gravimetric analysis, and Knudsen Cell Mass Spectrometry (KCMS) are used to assess Cs retention and substantiate lower evaporation during MW heating. Additionally, lower glass transition temperature (T_g​) and red shift in UV–Vis spectra in MW-melted glasses suggest increased non-bridging oxygens (NBOs) due to reduced Cs evaporation. Further, higher amount of cesium bismuth iodide (Cs₃Bi₂I₉) formation in MW-melted glasses confirms higher retention of Cs. These results demonstrate that MW heating effectively reduces Cs evaporation, improving its retention in the glass. Moreover, borosilicate glasses exhibited greater Cs evaporation than boron-free glasses, likely due to boron-assisted evaporation.