Foucaud Yann, Filippov Lev, Filippova Inna, Badawi Michael
Université de Lorraine, CNRS, GeoRessources, Nancy, France.
National University of Science and Technology MISIS, Moscow, Russia.
Front Chem. 2020 Apr 16;8:230. doi: 10.3389/fchem.2020.00230. eCollection 2020.
Recently, tungsten has drawn worldwide attention considering its high supply risk and economic importance in the modern society. Skarns represent one of the most important types of tungsten deposits in terms of reserves. They contain fine-grained scheelite (CaWO) associated with complex gangue minerals, i.e., minerals that display similar properties, particularly surface properties, compared to scheelite. Consistently, the froth flotation of scheelite still remains, in the twenty first century, a strong scientific, industrial, and technical challenge. Various reagents suitable for scheelite flotation (collectors and depressants, mostly) are reviewed in the present work, with a strong focus on the separation of scheelite from calcium salts, namely, fluorite, apatite, and calcite, which generally represent significant amounts in tungsten skarns. Albeit some reagents allow increasing significantly the selectivity regarding a mineral, most reagents fail in providing a good global selectivity in favor of scheelite. Overall, the greenest, most efficient, and cheapest method for scheelite flotation is to use fatty acids as collectors with sodium silicate as depressant, although this solution suffers from a crucial lack of selectivity regarding the above-mentioned calcium salts. Therefore, the use of reagent combinations, commonly displaying synergistic effects, is highly recommended to achieve a selective flotation of scheelite from the calcium salts as well as from calcium silicates.
近年来，鉴于钨在现代社会中的高供应风险和经济重要性，它已引起全球关注。就储量而言，矽卡岩是最重要的钨矿床类型之一。它们含有细粒白钨矿（CaWO），与复杂的脉石矿物共生，即与白钨矿相比具有相似性质，特别是表面性质的矿物。因此，在21世纪，白钨矿的泡沫浮选仍然是一个重大的科学、工业和技术挑战。本文综述了各种适用于白钨矿浮选的试剂（主要是捕收剂和抑制剂），重点是从钨矽卡岩中通常含量较高的钙盐，即萤石、磷灰石和方解石中分离白钨矿。尽管一些试剂能显著提高对某一种矿物的选择性，但大多数试剂在提供有利于白钨矿的良好整体选择性方面仍存在不足。总体而言，白钨矿浮选最绿色、最有效且最便宜的方法是使用脂肪酸作为捕收剂，硅酸钠作为抑制剂，尽管这种方法在针对上述钙盐的选择性方面存在关键不足。因此，强烈建议使用通常具有协同效应的试剂组合，以实现从钙盐以及硅酸钙中对白钨矿进行选择性浮选。
