Na-X zeolites were synthesized by Longkou oil shale ash with the alkaline fusion hydrothermal method.The effects of fusion temperature,ash to NaOH ratio,solid-liquid ratio,crystallization time and crystallization temp...Na-X zeolites were synthesized by Longkou oil shale ash with the alkaline fusion hydrothermal method.The effects of fusion temperature,ash to NaOH ratio,solid-liquid ratio,crystallization time and crystallization temperature on the crystallinity of zeolites were investigated.The synthetic products were characterized by Xray diffraction(XRD),scanning electron microscopy(SEM),Fourier transform infrared spectroscopy(FTIR),29Si nuclear magnetic resonance spectroscopy(29Si NMR)and N2 adsorption-desorption.The results showed that the conditions to synthesize Na-X zeolite were:Longkou oil shale ash to sodium hydroxide ratio 1:1.2 g・g^(-1),fusion temperature 600℃,solid-liquid ratio 1:4 g・mL^(-1),crystallization time 24 h and crystallization temperature 80℃.The zeolite with high crystallinity(91.32%)was synthesized:the product exhibiting octahedral particles observed by SEM,and the calculated Si/Al ratio in Na-X zeolite being 1.23 from^(29)Si MAS NMR spectra,which was consistent with the observation from XRD.展开更多
基金the National Basic Research Program of China(973 Program,Grant 2014CB744301).
文摘Na-X zeolites were synthesized by Longkou oil shale ash with the alkaline fusion hydrothermal method.The effects of fusion temperature,ash to NaOH ratio,solid-liquid ratio,crystallization time and crystallization temperature on the crystallinity of zeolites were investigated.The synthetic products were characterized by Xray diffraction(XRD),scanning electron microscopy(SEM),Fourier transform infrared spectroscopy(FTIR),29Si nuclear magnetic resonance spectroscopy(29Si NMR)and N2 adsorption-desorption.The results showed that the conditions to synthesize Na-X zeolite were:Longkou oil shale ash to sodium hydroxide ratio 1:1.2 g・g^(-1),fusion temperature 600℃,solid-liquid ratio 1:4 g・mL^(-1),crystallization time 24 h and crystallization temperature 80℃.The zeolite with high crystallinity(91.32%)was synthesized:the product exhibiting octahedral particles observed by SEM,and the calculated Si/Al ratio in Na-X zeolite being 1.23 from^(29)Si MAS NMR spectra,which was consistent with the observation from XRD.