改性高岭土结构特性研究

Study on structure characteristics of modified kaolin

考察了不同焙烧温度的高岭土分别经酸、碱改性后的结构特性.结果表明,焙烧温度为700～900℃时,强酸改性后偏高岭土的SiO2/Al2O3值(质量比)、比表面积和比孔容均显著增大,表面酸值增大且出现强酸中心;强碱改性后偏高岭土的SiO2/Al2O3值变化不明显,比表面积和比孔容均有所降低;强碱改性偏高岭土的表面酸值小于强酸改性偏高岭土的表面酸值.

The structure characteristics of kaolin modified by acid or alkali at different calcination temperature were investigated.The results showed that when the calcination temperature was in the range of 700-900℃,the SiO2/Al2O3 value(mass ratio),specific surface area and pore volume of metakaolin increased evidently after it was modified by strong acid,at the same time,the surface acid value increased too and strong acid center appeared.After strong alkali modified,the SiO2/Al2O3 value of metakaolin had no obvious change,and the specific surface area and pore volume decreased.The surface acid valume of metakaolin modified by strong alkali was less than that of metakaolin modified by strong acid.