隨著電子及電器產品普及，永久磁鐵的運用越來越廣泛。在過去幾十年來，釹鐵硼稀土磁鐵與釤鈷稀土磁鐵最具代表性，其中釤鈷磁鐵具有比較低的溫度係數，在180°C以上時，其磁能積、矯頑力及溫度穩定性和化學穩定性均超過釹鐵硼磁鐵，且最高溫度可達350°C。因此大量運用在航太領域。
本研究將釤鈷磁鐵粉末以2N的硫酸、5vol%的H2O2浸漬2小時，然後利用M4195與MTS9570兩種樹酯進行離子交換，分離釤鈷磁鐵之浸漬液，將其富集純化。
第一步除銅過程，將浸漬液先利用M4195螯合型樹酯進行吸附，因M4195在0.66pH值的環境下吸附 Cu的選擇性遠高於Sm、Co、Fe，在第2B.V的時候Sm、Co、Fe皆已經突破。因此使用M4195進行除銅，且使用2M氨水脫附，即可分離出銅，本階段銅回收率99.96%，純度為99.93%。並收集2~13B.V.含Sm、Co、Fe之交換尾液進行下一步研究。
第二步進行除鐵，利用MTS9570進行吸附。為避免提早突破，將其第一步收集之交換尾液後並稀釋一倍，使其鐵濃度調整成3500±500ppm、pH=0.55，因在Sm、Co、Fe三元溶液中，MTS9570對鐵有較高的選擇性，因此在此階段我們可以將鐵吸附，並且收集2~6B.V含Sm、Co之除鐵液進行下一步研究。由於Fe如果在pH值高的時候容易形成凝膠狀的氫氧化鐵，會堵住樹酯微小孔洞並造成脫附再生率低下，進而使樹酯失效。因此使用2N硫酸代替水進行水洗，以防pH升高，並且使用鹽酸進行氯化脫附，鐵的回收率78.95%，純度99.76%。
在上一步驟交換完後的Sm、Co二元溶液，由於M4195特性，須稀釋大倍數之進料才能吸附鈷，而稀釋原因，釤濃度的降低與液體的增加，導致處理效率不佳。因此先使用MTS9750進行吸附。因MTS9570交換之磺酸基高價數選擇性大於低價數，在Sm、Co二元溶液中Sm的選擇性遠大於Co，因為我們可以得到Co的交換尾液，即可獲得純度99.9%的Co。且MTS9570可有效富集釤、減少鈷，使Sm快速突破，因此將MTS9570吸附Sm之脫附液pH值調到3.5之後再進行M4195之吸附，即可獲得純度 99.9%的釤溶液。

In this study, samarium cobalt magnet powder was impregnated with 2N sulfuric acid and 5 vol% H2O2 for 2 hours, and then ion exchange was carried out using two resins, M4195 and MTS9570, to separate the impregnating solution of samarium cobalt magnet, and to enrich and purify it.
In the first step of removing copper, the impregnating solution is first adsorbed with M4195 chelating resin, because the selectivity of M4195 to Cu under the environment of 0.66pH value is much higher than that of Sm, Co, Fe. Therefore, using M4195 for copper removal, and using 2M ammonia desorption, copper can be separated, the copper recovery rate at this stage is 99.96%, and the purity is 99.93%. And collect 2~13B.V. Exchange tail liquid containing Sm, Co, Fe for further research.
The second step is to remove iron and use MTS9570 for adsorption. In order to avoid early breakthrough, the exchange tail liquid collected in the first step is doubled and diluted to make its iron concentration adjusted to 3500±500ppm, pH=0.55, and collect 2~6B.V iron removal solution containing Sm and Co for the next study. If Fe easily forms gelatinous iron hydroxide when the pH value is high, it will block the tiny pores of the resin and cause the desorption regeneration rate to be low, thereby making the resin ineffective. Therefore, 2N sulfuric acid was used instead of water for water washing to prevent the pH from rising, and hydrochloric acid was used for chlorination desorption. The recovery rate of iron was 78.95% and the purity was 99.76%.
The binary solution of Sm and Co after the exchange in the previous step, due to the characteristics of M4195, must be diluted by a multiple of the feed to absorb cobalt. The dilution causes a decrease in the concentration of samarium and an increase in liquid, resulting in poor treatment efficiency. Therefore, first use MTS9750 for adsorption. Because the selectivity of the sulfonic acid group exchanged by MTS9570 is higher than that of the low valence, the selectivity of Sm in the binary solution of Sm and Co is much greater than that of Co, because we can obtain the exchange tail liquid of Co, and the purity of 99.9% Co can be obtained. . And MTS9570 can effectively enrich samarium, reduce cobalt, and make Sm break through quickly. Therefore, after adjusting the pH value of the desorption solution of Ms9570 adsorbing Sm to 3.5, and then carrying out M4195 adsorption, a 99.9% purity samarium solution can be obtained.

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