(昆明貴金屬研究所 貴研鉑業(yè)股份有限公司 稀貴金屬綜合利用新技術(shù)國家重點(diǎn)實(shí)驗(yàn)室，昆明 650106)
摘 要: 研究固態(tài)還原鐵捕集法回收鉑族金屬二次資源。結(jié)果表明：在鐵精礦與鉑族金屬二次物料質(zhì)量比為1.5:1，還原溫度1220 ℃，還原時(shí)間6 h，還原劑配比9%，添加劑配比10%的條件下所得產(chǎn)物經(jīng)濕式磁選，獲得含鉑族金屬鐵粉，其中Pt、Pd和Rh含量分別為110.4、27.3和52.1 g/t，Pt、Pd和Rh回收率分別為98.6%、91.7%和97.6%。該過程的機(jī)理主要在于固態(tài)還原過程中微量鉑族金屬優(yōu)先轉(zhuǎn)化為原子態(tài)或原子團(tuán)簇，與新生金屬Fe中自由電子鍵合在一起，同時(shí)，新生γ-Fe與Pt，Pd和Rh具有相同的晶體結(jié)構(gòu)和相近的晶胞參數(shù)，從而形成合金；鐵氧化物還原為Fe，F(xiàn)e原子通過擴(kuò)散方式凝聚在一起形成晶核粒子，F(xiàn)e晶粒不斷聚集長大，還原產(chǎn)物通過球磨磁選分離，實(shí)現(xiàn)鉑族金屬的回收。
關(guān)鍵字: 鉑族金屬；固態(tài)還原；鐵捕集；回收
（Kunming Institue of Precious Metals, Sino-platinum Metals Co., Ltd., State Key Laboratory of Advanced Technologies for Comprehensive Utilization of Platinum Metals, Kunming 650106, China）
Abstract:The recovery of platinum group metal (PGM) secondary resource by iron trapping method based on solid state was investigated. The results show that a iron powder with 110.4 g/t Pt, 27.3 g/t Pd and 52.1 g/t Rh, and Pt, Pd, Rh recovery rates of 98.6%, 91.7% and 97.6%, respectively, is obtained, under the conditions of mass ratio of iron concentrate to PGM secondary resource 1.5:1, reducing temperature 1220 ℃, time 6 h, reductant ratio 9% and additive ratio 10%. The mechanism is that, during the reduction process, trace PGM transforms to atomic state or atomic cluster and bonds with free electrons in new iron metal. New γ-Fe is the same crystal structure and similar crystal cell parameters with Pt, Pd and Rh and forms alloys. The iron atom keeps together and forms crystal nucleus particle by diffusion way, the crystal grain grows up, and reduced product is performed to ball grinding-magnetic separation, realizing PGM recovery.
Key words: platinum group metal; solid state reduction; iron trapping; recovery
