以辉锑矿为原料放电等离子烧结快速制备黝铜矿Cu_(12)Sb_4S_(13)及反应机理

采用辉锑矿为原料成功制备出Cu_(12)Sb_4S_(13)块体。研究以Sb_2S_3矿物为原料时烧结工艺对Cu_(12)Sb_4S_(13)合成的影响。在400 ～ 440℃温度区间内均可快速合成Cu_(12)Sb_4S_(13)块体且二次烧结能够进一步减小中间相CuSbS_2和Cu_3SbS_3。第二相Cu_3SbS_4和残留相CuS随着烧结时间的延长而降低。二次烧结前进行机械化球磨处理,干磨比湿磨更容易减小残留相。初次烧结块体的断面SEM和EDS能谱分析表明内部存在Cu或Cu_2S颗粒团聚现象。适当降低Cu或CuS摩尔量(化学计量比0.1 mol)能促进烧结块表面反应进行。烧结过程中,硫磺蒸汽压的导致烧结块表面成分和内部粉末的成分不同。

Utilization of stibnite ore Sb2S3 as raw material for the preparation of tetrahedrite Cu12Sb4S13 and its reaction mechanism

Stibnite mineral Sb2S3 was employed as starting material for the synthesis of tetrahedrite Cu12Sb4S13 bulks by pulse electric sintering. The influences of sintering conditions (temperature and time), secondary sintering, ball milling on the preparation of Cu12Sb4S13 compacts were systematically investigated. High pure Cu12Sb4S13 can be quickly obtained by the optimized sintering condition. Cu12Sb4S13 can be synthesized rapidly in the temperature range of 400-440 ° C, and the secondary sintering can further reduce the mesophase CuSbS2 and Cu3Sb4S3. The second phase Cu3SbS4 and the residual phase CuS decrease with the increase of sintering time. It is easier to reduce the residual phase in dry grinding than in wet grinding. SEM and EDS analysis of the primary sintering bulk show that there is agglomeration of Cu or Cu2S particles in the matrix. Properly reducing the molar amount of Cu or CuS (stoichiometric ratio 0.1mol) can promote the surface reaction of agglomerates. In the sintering process, the sulfur vapor pressure results in the difference of the surface composition and the inner composition.