集中式粉末钙源皂化稀土萃取有机相的工艺研究与工业应用

Technological Research and Industrial Application of Centralized Saponification with Calcium Hydroxide Powder of Rare Earth Extraction Organic Phase

研究了采用粉末钙源直接皂化稀土萃取有机相。试验结果表明,用粉末钙源直接皂化P507有机相和环烷酸有机相,有机相皂化值分别达0.55 mol/L和0.72 mol/L,且外观清亮,流动性好。将钙皂有机相与氯化稀土料液进行萃取反应,P507有机相的分相时间为40 s,稀土负载量为0.19 mol/L;环烷酸有机相的分相时间为180 s,稀土负载量为0.19 mol/L。根据此试验数据开发了集中式粉末钙源直接皂化工艺,该工艺已经过多年工业化运行,结果表明,粉末钙源直接皂化P507有机相、环烷酸有机相,流动性好,分相快,对产品质量影响小,对有机相无长期不利影响;皂化成本只需液碱皂化的16.5%;由于皂化剂是粉末,无需制乳,与有机相直接发生皂化反应,与液碱皂化相比,废水大大减少,环保效益良好。

The direct saponification of rare earth extraction organic phase with calcium hydroxide powder was studied.The experimental results show that the saponification values of P507 organic phase and naphthenic acid organic phase are 0.55 mol/L and 0.72 mol/L,respectively, with clear appearance and good fluidity through the process of direct saponification by using calcium hydroxide powder.When the calcium saponified organic phase is subject to extraction reaction with rare earth chloride feed liquid, the separation time of P507 organic phase is 40 s with the rare earth load of 0.19 mol/L,and the separation time of naphthenic acid organic phase is 180 s with the rare earth load of 0.19 mol/L.Based on the test data, a centra-lized calcium hydroxide powder direct saponification technology was developed.After years of industrial operation, the results show that calcium hydroxide powder directly saponifies the P507 organic phase and the naphthenic acid organic phase with good fluidity, fast phase separation, little impact on product quality, and no long-term adverse effects on the organic phase.And the saponification cost is only 16.5% of that of liquid alkali.Since the saponifier is a powder, there is no need for emulsion and the saponification reaction with the organic phase directly occurs.Compared with the saponification of liquid alkali, the wastewater greatly reduces and the environmental benefits are quite good.