煤矸石-滑石-菱镁矿低温合成堇青石研究

Study on Cordierite Synthesized at Low Temperature With Coal Stone-Magnesite-Talc

以煤矸石、滑石和菱镁矿为原料,采用固相烧结反应法,对低温合成堇青石的机理和工艺进行了研究。结果表明,由于配料系统与常用高岭土-滑石-氧化铝系统相比,未引入活性较差的氧化铝原料,所用原料在加热过程中分解产物的活性均较高,使堇青石的合成温度由1370℃以上降低到1350℃。合成堇青石源于两种反应机理,其中,镁铝尖晶石与方石英反应生成堇青石的反应活化能较高,是决定合成温度和保温时间的主要因素。

The cordierite was synthesized by solid reaction process at low temperature with the mixture of talc, magnesite and coal gangue. The synthesis mechanism and influence of the process were investigated.The results reveal that compared with ordinary kaolin-talc-alumina system the synthesis temperature can be lowered from 1370℃ to 1350℃ because no inactive alumina was introduced and some active substances would occurred from the source materials. The occurrence of cordierite depends on two reactions, among which the reaction between magnesium aluminium spinel and cristobalite is predominant due to its relative high activation energy, and mainly affect the synthesis temperature and soaking time.