Preparation of Bauxite-Based Homogenized Mullite Grogs with Bauxite and Coal Gangue

Abstract

The sintering behavior, physical properties and heat processing changes of bauxite-based homogenized grogs prepared by homogenization process and high temperature sintering using bauxite as starting material were investigated. Results show that the bauxite-based mullite can be synthesized by the method, sintering temperature with and without MgO/CeO2sintering aids are 1600°C and 1700°C separately, the mullite with apparent porosity of＜1.0% and 2.5%, bulk density of ≥2.87g•cm-3and 2.75g•cm-3, Refracteriness-Under-Load(RUL) 1600°C and 1620С; changes in the heat processing is divided into three stages: dehydration stage(400°С~900°С ), primary mullitization stage(1000°С ~1200°С) and secondary mullitization stage(>1200°С).

Study on Sintering Properties of Al₂O₃-70 Natural Mullite by New Processes

“…Combined with bulk density and the linear changes may safely draw the conclusion: 70 green sample's sintering began in 1500 °C, after 70 green sample sintered at 1600 °C for 4h, the sample's bulk density is highly improved; 70 green sample has not complete sintering at 1600 °C. and at this temperature, extending holding time will not further improve the density of the sample; after sintered at 1600°C for 4h ,the sample's bulk density is 2.82 g٠cm -3 , Yang Zhong Zheng et al [6] sintering bauxite-based mullite homogeneous clinker Al 2 O 3 -70 at 1700°C,the sample's bulk density is 2.75 g٠cm -3 , so the new process is more advantageous to densification. 70 green sample's microstructure and phase composition.…”