A NEW METHOD OF DETERMINATION OF CALCIUM ORTHOPHOSPHATE AND ASSOCIATED IMPURITIES BY THERMOGRAVIMETRY AND DERIVATIVE THERMOGRAVIMETRY

Calcium orthophosphte (TCP) is known to be a nutritional additive in processed foods and wheat flour. Only pure salt is highly toxic to stored product insects. However, commercial salts were found to contain other monobasic and dibasic calcium phosphates and carbonates of calcium and magnesium which reduce insecticidal potency and affect food quality. The conventional methods of analysis of these salts are not only cumbersome but are not distinguished from each other clearly. A new method of identification of pure tricalcium phosphate and other associated impurities by thermogravimetry and derivative thermogravimetry has been described and the parameters for the identification of the nutritional protectant salt have been characterized.