Investigation of citrate synthesis process from Ln-carbonate obtained by processing Dong Pao ore

Rare earth products have used largely in the field of industry and agriculture, especially in agriculture.The application of Ln-products with organic radical, like Ln-citrate in animal husbandry have been developed at China from 20 years ago. And now, Western Europe countries have been used Ln-products in animal husbandry in order to enhance animal growth and ability for resistance of diseases.Ln-citrate was synthesized from the Ln-carbonate obtained by processing Dong Pao ore by technological flow-sheet such as: Dissolution of rare earth carbonate by HCl of 15%; Precipitation of rare earth hydroxide by NH₄OH of 8%; Washing of rare earth hydroxide by water; Dissolution of rare earth hydroxide by citric acid of 4M; Synthesization of rare earth citrate was impacted by temperature, time and concentration of citric acid. Experiments were conducted and parameters of process have been determined: temperature of 90℃ ; time of reaction 5h; acid concentration of 4M and the efficiency of process 95% (author)