粉煤灰水热法合成沸石及其表征

Zeolite from Coal Fly Ash by Hydrothermal Synthesis and Characterization

本文考察了4M氢氧化钠水溶液和121℃条件下水热反应时间对粉煤灰合成产物的影响,用粉末X-射线衍射(PXRD)、扫描电镜(SEM)、差式扫描量热(DSC)以及热重(TG)等手段对产物进行了分析表征。Jade 6.0软件分析表明,粉煤灰水热反应合成了羟基方钠石,其晶胞参数为a=b=c=0.906 nm。随着水热时间的延长,合成羟基方钠石的结晶度和含量增加。合成产物呈表面粗糙的球状,粒度随水热时间延长而增大。热分析结果表明合成羟基方钠石中含有结晶水,其分子式为Na8Al6Si6O24(OH)2·2H2O。粉煤灰400 min水热合成产物中的二水羟基方钠石纯度约为65.32%。

The effects of hydrothermal synthesis time on the coal fly synthetic products were investigated under 4M NaOH and 121℃ conditions. The synthetic products were analyzed and characterized using X- ray diffraction, SEM, DSC and TG. Jade 6.0 software analysis showed that coal fly ash hydrothermal synthesis products are hydroxy sodalite, and its unit cell parameters are a = b = c = 0. 906 nm. With the extension of hydrothermal time, the crystallinity and content of hydroxy sodalite increase. The synthesized product is spherical with roughness surface, grain size increases with hydrothermal time. Thermal analysis showed that the hydroxy sodalite contains crystal water, and its formula is Na8Al6Si6O24 （OH）2 · 2H2O. The product synthesized from coal fly ashes through 400 min hydrothermal treatment contains about 65. 32wt% of dihydrate hydroxysodalite.