高岭土同时吸附Na,Pb化合物的机理研究

Simultaneous Adsorption of Na and Pb Compounds by Kaolinite

使用熔点分析仪考察了高岭土吸附Na、Pb过程中产物及高岭土原样随温度升高的熔融情况,并在管式炉中800℃、1000℃、1200℃下进行了高岭土分别及同时吸附Na、Pb的实验,研究不同温度、不同高岭土/金属摩尔比以及不同碱金属/重金属摩尔比对吸附结果的影响。使用FSEM、XRD和XRF等手段研究产物的形貌、晶体组成以及高岭土对金属的固定率等。结果表明:1000℃是Na/kaolin和Na/Pb/kaolin系统生成产物开始熔融的温度,Na、Pb同时存在时熔融现象加剧;在1000℃时Na的存在抑制了高岭土与Pb的反应,并且Na量越多,温度越高,这种抑制作用越强烈;Pb对高岭土吸附Na的影响并不显著。

As the temperature grows,the melting situation of compounds produced by reaction between Na,Pb compounds and kaolin was investigated in the melting point analyzing furnace.The adsorption experiments of Na,Pb compounds by kaolin in a lab-scale fixed bed reactor were carried out at 800,1000 and 1200℃,respectively,to study the influence of different temperatures,mole ratios of kaolin/metal and Na/Pb on the reaction.The surface morphology,crystal compositions and adsorption efficiency were examined by FSEM、XRD and XRF,respectively.The experimental results showed that at about 1000℃,melting occurred on the alone Na/kaolin and multiple Na/Pb/kaolin system and aggravated with presence of both Na and Pb.Moreover,the existance of Na inhibited the reaction between kaolin and Pb compounds,and the inhibition got stronger when more Na was added,or the temperature was increased.However,the effect of Pb on Na capture by kaolin was not observed obviously under the experimental conditions.