烧结温度对煤矸石多孔材料物相与性能的影响

Influence of Sintering Temperature on the Phase and Properties of Gangue Porous Materials

以煤矸石为原料、硅溶胶为胶凝剂泡沫胶凝法制备煤矸石多孔材料,研究烧结过程中的物相变化和烧结温度对多孔材料抗压强度和线收缩率的影响。研究结果表明,500~800℃烧结时在低衍射角衍射峰强度降低、某些衍射峰消失,煤矸石中高岭石脱水生成偏高岭石;1150℃烧结时发生α-石英向α-鳞石英的相变和Al2O3与Si O2反应生成莫来石而出现鳞石英相与莫来石相。随着烧结温度的升高,多孔材料抗压强度和线收缩率均逐渐增大。密度约0.8 g/cm^3的煤矸石多孔材料1000℃烧结后抗压强度3.85 MPa,线收缩率6.89%。

The gangue porous materials were prepared using coal gangue as raw material and silica sol as gelling agent by foam gel method. The phase transformation during sintering and effect of sintering temperature on the compressive strength and the linear shrinkage rate were investigated. It has been shown that at the temperature range of 500-800 ℃ the intensity of peak decreased and some peaks disappeared at low diffraction angle,kaolinite in the coal gangue is dehydrated to generate metakaolin;the phase transition of alpha-quartz to alpha-tridymite and reaction of Al2O3 with Si O2 to form mullite happened with result of occurrence of phases of tridymite and mullite at 1150 ℃. The compressive strength and the linear shrinkage rate of the gangue porous materials have gradually increased with the increase of sintering temperature. The gangue porous material with a density of about 0. 8 g / cm^3 sintered at 1000 ℃ has the compressive strength of 3. 85 MPa and the line shrinkage rate of 6. 89%.