固体废弃物铝灰和粉煤灰原位合成Spinel-Sialon复相材料的研究

Study on Synthesis of Spinel-Sialon Multiphase Material from Fly Ash and Aluminum Dross In-situ Reaction

本文利用铝灰和粉煤灰为原料,经原位铝热还原氮化法合成了Spinel-Sialon复相材料。通过XRD、SEM、EDS等分析手段,研究了合成温度和还原剂铝的添加量对合成产物物相及微观形貌的影响。结果表明:合成Spinel-Sialon的优化工艺参数为铝的添加量为过量100%、合成温度为1550℃,保温时间3 h,合成得到发育良好的柱状β-Sialon及八面体形的镁铝尖晶石。合成温度、还原剂铝的添加量均是影响氮化产物的重要因素。随着温度的升高或还原剂铝的添加量增多,Al2O3越来越少,β-Sialon和镁铝尖晶石均增多,且β-Sialon的Z值增大,MgAl2O4转变成富铝尖晶石。

Spinel-Sialon multiphase material were successfully synthesized by the aluminothermic reduction and nitridation reaction using aluminum ash and fly ash as raw materials.The effects of synthesizing temperature and content of aluminum as the reducing agent on the phase composition and microstructure of the products were investigated by XRD,SEM with EDS.The results showed that the optimal technical factors for synthesizing Spinel-Sialon composites were as followings: reaction temperature was 1550 ℃,holding time was 3 h,and content of aluminum was 100% over theory content.The synthesized products were made up of columnar β-Sialon crystals and octahedron-like Spinel crystals.Synthesizing temperature and content of aluminum were both the important influence factors on the phase composition of the products synthesized by aluminothermic reduction-nitridation.As the temperature or aluminum incrceasing,β-Sialon and Spinel increased,while α-Al2O3 decreased.Moreover,the Z value of β-Sialon increased and MgAl2O4 changed to alumina rich spinel.