Abstract

Most commercial applications of phosphorus-containing materials are based on phosphoric acids and the phosphates. Uses, other than as fertilizer, include applications in detergency, foods and food processing, dental materials, dentifrices, metal surface treatments, flame retardency, etc. Structures and properties of orthophosphoric acid and condensed phosphoric acids are presented. The manufacture of technical- and food-grade phosphoric acids by thermal and wet acid purification processes, as well as some of the uses of the various phosphoric acids, are discussed.

The chemistry and properties of orthophosphates and condensed phosphates are presented. Emphasis is placed on alkali metal and calcium salts and their solution properties. Properties specific to condensed phosphate salts such as hydrolysis and metal ion complexation are outlined. Manufacturing schemes for the phosphates are described and attention is given to the control of product properties.