Synthesis And Characterization Of Novel Extractant And Extraction Of Rare Earth,Cobalt,Nickel

In recent years, designing and synthesizing of novel extractant which is high efficient toward metals have received more and more scientists’ attentions. In this paper, we have synthesized a series of extractants and organophosphorus extractants and investigated their properties for Ce, F, Co, Ni and other extraction. The results that have obtained in those experiments can provide some basic data in the separation process. The details are as follows:1. In this paper, structure of P2N1 O has been characterize by NMR. Effects of different variables on the extraction of Cerium(Ⅳ), fluorine, hydrogen peroxide and rare earth, such as the concentrations of acid, extractant and solvent, different kinds of amendment and saturated loaded extraction were carried out. The extraction rate of the extraction agent P2N1 O was 33.63% when the concentration of H+ was0.3517 mol/L. Preliminary conjecturing by slope method, the mechanism of the phosphat amide extraction agent extracting cerium was neutral complexation mechanism, and the molecular ration of extraction agent to cerium in extract compound was 1:1. The extraction rate of different diluent extraction system for cerium and fluorine decreases in the following order:n-heptane>kerosene>toluene>chloroform. Adding phase modifier made the extraction rate of cerium significantly decreasing. Because of the saturation capacity of P2N1 O extracting cerium was 55 g/L and the saturation capacity of P2N1 O extracting fluorine was 71.25 g/L, the extraction agent P2N1 O could be used for extracting cerium and fluorine in sulfuric acid medium.2. P3 N has been synthesized and studied for the extraction and separation of cabolt and nickel. The effects of acidity, phase ratio, temperature, extracting time and saturated loaded extraction on cabolt and nickel were studied. Compared with high acidity environment, the extraction rate of the extraction agent P1N2 O extracting cobalt was higher in low acidity environment. When it was different on acidity, the ratio of phase, temperature and extracting time, the extraction rate of extracting coalt were all above 78%, and the highest extraction rate of extracting nickel was only3.11%. Preliminary conjecturing by slope method, the mechanism of the phosphateamide extraction agent extracting cobalt was neutral complexation mechanism, and the molecular ratio of extraction agent to cobalt in extract compound in 1:1.3. A novel neutral secondary amine phosphamide extractant P3 N was synthesized, which were studied the effects of acidity, phase ratio, temperature and extracting time on separating Ce, Th and rare earth. The extractant P3 N had strong extraction performance for cerium. The mechanism of the phosphate amide extractant extracting cerium, thorium and lanthanum was neutral complexation mechanism, the molecular ratio of extraction agent to cerium, thorium and lanthanum were all 1:1. The extraction rate of cerium, lanthanum and thorium decreases with the increase of ratio. When O/A was between 1 and 3, the extraction rate of cerium was obviously higher than the extraction rate of thorium and lanthanum. The best temperature of P3 N extracting cerium was 25℃.