(武汉理工大学 资源与环境工程学院，武汉 430070)
摘 要: 研究捕收剂油酸钠体系下HEDP(羟基乙叉二膦酸)抑制剂分离磷灰石与方解石的可行性，单矿物浮选试验表明，油酸钠对磷灰石和方解石均有较好的捕收性能，当pH值为9时，HEDP抑制剂能显著抑制方解石的浮选，而对磷灰石的抑制性能较小。人工混合矿浮选试验表明，HEDP抑制剂较好地实现了磷灰石与方解石的分选分离。Zeta电位测试结果表明，HEDP能吸附在磷灰石和方解石表面，但是油酸钠能吸附在经HEDP作用的方解石表面而不能吸附在经HEDP作用的磷灰石表面，结合HEDP分子结构和矿物表面原子排布分析，HEDP抑制剂结构式中O (P=O)与O (P=O) 原子间距与方解石表面Ca—Ca原子间距匹配性较好，而与磷灰石表面Ca—Ca原子间距几何匹配性较差。此外，磷灰石与方解石的表面阴离子组分不同也导致了二者与HEDP的静电排斥力有区别。HEDP在方解石表面的吸附强于较磷灰石表面，从而实现磷灰石浮选体系对方解石的选择性抑制。
关键字: 磷灰石；方解石；油酸钠；HEDP；浮选分离
（School of Resources and Environmental Engineering, Wuhan University of Technology, Wuhan 430070, China）
Abstract:A depressant hydroxy ethylidene diphosphonic acid (HEDP)was introduced as the depressant for the flotation separation of apatite from calcite using sodium oleate (NaOl) as a collector. The microflotation results show that both apatite and barite have good floatability in the presence of NaOl. The addition of HEDP significantly depresses the calcite flotation while it only slightly affects apatite flotation. Mixed minerals flotation results confirm that the efficient flotation separation of apatite from calcite can be achieved using HEDP as a depressant. Zeta potential measurements indicate that HEDP can interact with both apatite and calcite surfaces. HEDP-treated apatite prevents the NaOl adsorption onto the calcite surface rather than the apatite surface. Considering the molecular structure of HEDP and the atomic arrangement of mineral surfaces, the O(P=O)—O (P=O) distance of HEDP only matches well with the Ca—Ca distance on the calcite surface, which may lead to the stable HEDP adsorption onto the calcite surface instead of apatite surface. In addition, the different anionic groups on apatite and calcite surfaces also cause the various electrostatic repulsive forces with HEDP. Thus, the adsorption of HEDP onto the calcite surface is stronger than that onto the apatite surface, then, the selective depression of calcite can be achieved in the apatite flotation.
Key words: apatite; calcite; sodium oleate; HEDP; flotation separation
