Effect of Ru/Pd on Precipitation Phases and Morphologies of Platinum Group Metals from Simulated HLLW Glass

doi:10.16552/j.cnki.issn1001-1625.2025.0595

Abstract

Abstract: The precipitation behaviour of platinum group metals in glass melts remains a key research focus within high-level liquid waste (HLLW) vitrification technology. The present study investigated the effects of varying mass ratio of RuO₂ and PdO (Ru/Pd), melting durations, and melting temperatures on the precipitation phases and morphologies of platinum group metals in glass melts. Test results from XRD and SEM-EDS indicate that samples with different Ru/Pd primarily form aggregates of granular RuO₂ and spherical Pd metal. A decrease in the Ru/Pd, or a prolongation of the melting duration, has been shown to increase the average diameter of Pd spheres. Furthermore, it is observed that the transformation of spherical to irregular Pd metal occurrs, resulting in a distinctive structure with Pd metal covered by RuO₂. It has been demonstrated that elevated melting temperatures significantly promote the reduction of PdO. RuO₂ and Pd metal are the predominant phases in glass melts at melting temperature of 1 000 ℃ and above.

Key words: vitrification, high-level liquid waste, platinum group metal, Ru/Pd, precipitation behaviour, microstructure of Pd metal covered by RuO₂

CLC Number:

TQ171

ZHU Qiaofeng, MENG Xiangda, FENG Jinyang, NIU Chenchen, LIU Yujie, ZHAO Qingbin, XU Kai. Effect of Ru/Pd on Precipitation Phases and Morphologies of Platinum Group Metals from Simulated HLLW Glass[J]. BULLETIN OF THE CHINESE CERAMIC SOCIETY, 2025, 44(12): 4557-4566.

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