(武漢理工大學(xué) 資源與環(huán)境工程學(xué)院，武漢 430070)
摘 要: 研究捕收劑油酸鈉體系下HEDP(羥基乙叉二膦酸)抑制劑分離磷灰石與方解石的可行性，單礦物浮選試驗(yàn)表明，油酸鈉對(duì)磷灰石和方解石均有較好的捕收性能，當(dāng)pH值為9時(shí)，HEDP抑制劑能顯著抑制方解石的浮選，而對(duì)磷灰石的抑制性能較小。人工混合礦浮選試驗(yàn)表明，HEDP抑制劑較好地實(shí)現(xiàn)了磷灰石與方解石的分選分離。Zeta電位測(cè)試結(jié)果表明，HEDP能吸附在磷灰石和方解石表面，但是油酸鈉能吸附在經(jīng)HEDP作用的方解石表面而不能吸附在經(jīng)HEDP作用的磷灰石表面，結(jié)合HEDP分子結(jié)構(gòu)和礦物表面原子排布分析，HEDP抑制劑結(jié)構(gòu)式中O (P=O)與O (P=O) 原子間距與方解石表面Ca—Ca原子間距匹配性較好，而與磷灰石表面Ca—Ca原子間距幾何匹配性較差。此外，磷灰石與方解石的表面陰離子組分不同也導(dǎo)致了二者與HEDP的靜電排斥力有區(qū)別。HEDP在方解石表面的吸附強(qiáng)于較磷灰石表面，從而實(shí)現(xiàn)磷灰石浮選體系對(duì)方解石的選擇性抑制。
關(guān)鍵字: 磷灰石；方解石；油酸鈉；HEDP；浮選分離
（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
