磷改性对γ－Al_2O_3物化性能的影响

EFFECT OF PHOSPHATE MODIFICATION ON THE CHEMICAL AND PHYSICAL PROPERTIES OF γ-Al_2O_3

用实验方法考察了磷改性对γ－Ａｌ＿２Ｏ＿３的物理和化学性能的影响，研究表明，磷酸盐与γ－Ａｌ＿２Ｏ＿３的反应容量有限，且存在着一个平衡点，磷改性在一定程度上能降低γ－Ａｌ＿２Ｏ＿３的表面积和孔体积，并同时能改变γ－Ａｌ＿２Ｏ＿３的表面酸性，使γ－Ａｌ＿２Ｏ＿３表面酸强度减弱。

The chemical and physical properties of γ-Al_2O_3 modi fied by phosphate wereinvestigated,The results show that γ-Al_2O_3 modified by the phosphate solution withappropriate concentration can reduce the surface area and the pore volume of γ-Al_2O_3 to someextent.The acidity was measured by using NH_3-TPD technology,It shows that the addition ofphosphate can accomodate acid strengh distribution on the surface of γ-Al_2O_3 and convert thestrong acid sites into the medium and weak acid sites.