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A solid ternary mixture consisting of NaF,silicon and one metal oxide such as La2O3,CeO2,Pr6O11,Nd2O3,and Y2O3 was prepared and usedas de-fluorinated reagent for CF4 decomposition.The results show that 90% conversion of CF4 can be reached initially over NaF-Si-La2O3,NaF-Si-CeO2,NaF-Si-Nd2O3,and NaF-Si-Y2O3 at 850 C.The fresh and used reagents were characterized using XRD and XPS techniques.It was found that the active components of NaF and metal oxides in NaF-Si-CeO2,NaF-Si-Pr6O11,NaF-Si-Nd2O3,and NaF-Si-Y2O3 weretransformed into inert phases of mixed metal fluorides and silicates,respectively,resulting in an ineffective utilization of these de-fluorinatedreagents,whereas no inert phases from NaF and La2O3 can be observed in the used NaF-Si-La2O3,indicating the NaF-Si-La2O3 reagent couldbe utilized more efficiently than the other reagents in CF4 decomposition.
A solid ternary mixture consisting of NaF, silicon and one metal oxide such as La2O3, CeO2, Pr6O11, Nd2O3, and Y2O3 was prepared and usedas de-fluorinated reagent for CF4 decomposition. The results show that 90% conversion of CF4 can be before setting over NaF-Si-La2O3, NaF-Si-CeO2, NaF-Si-Nd2O3, and NaF-Si-Y2O3 at 850 C. The fresh and used reagents were characterized using XRD and XPS techniques. NaF and metal oxides in NaF-Si-CeO2, NaF-Si-Pr6O11, NaF-Si-Nd2O3, and NaF-Si-Y2O3 were formed into inert phases of mixed metal fluorides and silicates, respectively, resulting in an ineffective utilization of these de -fluorinatedreagents, no no inert phases from NaF and La2O3 can be observed in the used NaF-Si-La2O3, indicating the NaF-Si-La2O3 reagent could be more efficiently than the other reagents in CF4 decomposition.