Study On Emission Reduction Of Light Rare Earth Ore Nd/Sm In Group With Pre-separation Extraction Methodology

We are a big country of Rare Earth resources, production, export and consumption. The elements of RE have great application in high technology. The separation of RE is the premise of RE application, P507 is the important extraction solvent of RE separation presently. The wastewater emissions of RE separation industry can damage the environment. Development of RE separation process is pursuit of high efficiency, friendly environment and zero emissions. The pre-separation extraction method is the most advanced process of RE extraction and separation in recent years, according to light RE raw material, adopt pre-separation extraction method, propose new separation process of light RE’s extraction and separation (Patent has been applied.) This new technology can reduce the consumption of chemical materials and reduce wastewater emissions.This Paper is a part of study for the new technology of light RE’s extraction and separation, the specified study contents are:through the experiment of light RE single stage extraction to measure technology parameters and determine technology conditions, carried out the experiment of light RE multistage countercurrent extraction and pre-separation; according to the experiment of multistage countercurrent extraction exit loaded organic single-stage washing to measure technology parameters and determine technology conditions, carried out the experiment of multistage countercurrent extraction exit loaded organic phase multistage countercurrent washing pre-separation. On the basis of these experimental data, made comparison of the important technical and economic index for pre-separation and extraction light RE Nd/Sm grouping new technology and traditional Nd/Sm grouping technology.The results of study shows:when the selected extraction rate is 8% or 10%, 90%La ～Nd elements of light RE mine can be removed by 5 stage countercurrent extraction, obtained purity of 99.99% La ～Nd elements. And obtained a percentage of 70%Sm ～element loaded organic phase at the same time. When the selected washing rate is 33%, the light RE elements can be washing into aqueous phase by 6 stage countercurrent washing experiment, and obtained purity of 99.9%Sm～Lu mixed RE elements.Compared to the economic technology index of pre-separation and extraction light RE Nd/Sm grouping technology and traditional Nd/Sm grouping technology:The wastewater emissions was reduced 59.11%, the consumptions of ammonia was 43.4% less than traditional, the consumptions of hydrochloric acid was reduced 76.23%, the total volume of extraction tank was reduced 79.05%. The pre-separation extraction method of light RE Nd/Sm grouping new technology not only can reduce the emissions of industrial wastewater and the consumptions of chemical materials, but also can improve processing capabilities, reduce production costs, and improve the economic benefits of the enterprise, is a technology process that would help RE separation process greening. Has the prospect of enterprise application, has important significance for the production of RE separation industry.