凹凸棒土热改性对玉米秸秆稀酸水解液脱色的研究

采用焙烧酸化法对凹凸棒土进行了改性,通过单因素实验对凹凸棒土的热改性条件进行了优化,且采用N2吸附-脱附、X射线衍射、扫描电镜等表征手段对其脱色机理进行了研究。结果表明,对玉米秸秆稀酸水解液的脱色效果最佳的凹凸棒土热改性条件:450℃焙烧2 h、酸浓度10%。酸化作用使凹土内粒间杂质胶结物和碳酸盐矿物分解,疏通内部孔道,H+与凹土结构内阳离子置换,增大比表面积,改善其表面特性;焙烧活化可除去不同状态的水,改变其结构,增大孔容和比表面积;两者结合处理使颗粒白土的吸附脱色能力提高。

study on the decoloriZation of corn straW dilute acid hydrolysate With thermal modified attapulGite

The calcined acidified method was adopted to the modified attapulgite,and the optimized prepa-ration conditions was obtained by the single factor experiments. The decoloring mechanism of particle clay was studied by BET,XRD,FE-SEM and so on. The result shows that the decolorization rate was best with calcination temperature 450℃ and 2 h and sulfuric acid concentration 10%. The acid activation made the intergranular impurities inside the particle clay and carbonate minerals decomposition. That degradated the channel,increased the surface area and replaced the metal ions to improve the surface properties;the cal-cined thermal activation removed the water during the attapulgite to dredge the channel and improve the structure,increase the pore volume and the specific surface area. The combination of calcination and acid-ification improved the adsorption decolorizing ability of the particle clay.