众所周知,用作填料和涂料的粘土,尤其是高岭土,其使用价值与其白度和亮度有直接关系。美国多数高岭土矿都受色泽污染。有些原矿不经加工就具有一定白度,而另一些则需采用精加工技术才能改善白度和亮度,从而增加其使用价值。选择性絮凝加工,使影响色泽的某些杂质能被除去,产品白度改善。连二亚硫酸盐的漂白技术已应用多年,在一定程度上能明显改善粘土矿物的白度和亮度。但是,有大量粘土采用上述方法处理,并不能改善白度和亮度,以适于涂料和填料。这类粘土与白、 It is well-known that clays, especially kaolins, used as fillers and coatings have a direct relationship with their whiteness and brightness. Most U.S. kaolin mines are contaminated by color. Some ores have a degree of whiteness without processing, while others require finishing techniques to improve whiteness and brightness, thereby increasing their value. Selective flocculation processing, so that some impurities affect the color can be removed, the product whiteness improved. The dithionite bleaching technology has been used for many years, to a certain extent, can significantly improve the whiteness and brightness of clay minerals. However, a large amount of clay treated in the above manner does not improve whiteness and brightness to suit paints and fillers. Such clay and white,