活性白土的化学改性及其作用机理研究

为了探讨活性白土的化学改性及其作用机理,对活性度最高和脱色率最大的两种典型活性白土,分别采用Ca(OH)2为改性剂进行无机改性和十六烷基三甲基胺为改性剂进行有机改性。实验结果表明,采用Ca(OH)2改性时,Bronsted酸活性中心和Lewis酸活性中心均可参与反应,以脱色率最高的活性白土为原料,阴离子交换容量可达1.404 mmol/g;采用十六烷基三甲基胺改性时,只有Bronsted酸活性中心参与反应,以活性度最高的活性白土为原料,有机烧失量可达0.775 mmol/gMMT。XRD分析表明所有改性活性白土的层间距均增加。采用一价阳离子改性时,反应比较容易,可采用简单的湿法工艺;采用二价阳离子改性时,反应比较困难,必须采用温度较低的干燥反应工艺。

Study on chemical modification of activated clay and its mechanism

The activated clay with the largest bleaching rate were organically modified by Ca(OH)2 and those with the largest activated degree were organically modified by cetyl-trimethyl amine to study the chemical modification and mechanism of the activated clay.The results showed that reaction took place not only in the activated centers of Bronsted acid but also in those of Lewis acid and that the modified amount was 1.404 mmol/g when the activated clay were modified by Ca(OH)2.However,reaction took place only in ...