[Application of IR spectrum to the research on coordination mechanisms of organic carboxylic acid during homogeneous precipitation].

Infrared (IR) spectrum, X-ray diffraction (XRD) and transmission electron microscope (TEM) were used to study and characterize the coordination mechanisms, products and morphology of organic carboxylic acid during homogeneous precipitation in the system of Ce(NO3)2 x 6 H2O and urea solution. The results showed that monocarboxylic acid stearic acid played a role of surfactant, and the product was still orthorhombic Ce2O(CO3)2 x H2O with a high crystallization degree. In turn, duality-carboxylic acid tartaric acid and tri-carboxylic acid citric acid were combined with Ce3+ to form chelate citric acid and cerium tartaric acid, respectively. The results were caused by different mechanisms of reaction in the solution.