Starches can adsorb on and depress copper-activated pyrite desirably during flotation, an important process in ore mineral extraction. In order to develop structure/function relationships, adsorption on and depression properties of copper-activated pyrite at pH 9 by normal wheat starch (NWS) and high-amylose wheat starch (HAW), dextrin, and a range of oxidized normal wheat starches (peroxide and hypochlorite treated) were investigated. Adsorption isotherms and bench flotation performance were compared with kinematic viscosity, molar mass distribution, surface coverage, and substituted functional groups assay. The differences in molar mass distribution and substituted functional groups among oxidized starches had little influence on the depression of copper-activated pyrite. However, the introduction of -C=O and -COOH substituents, combined with depolymerization, improved solubility and dispersibility, reduced aggregated structures, and strengthened surface binding of oxidized polymers, compared with NWS and HAW. At high concentrations, HAW, NWS, and dextrin were adsorbed onto the pyrite surface more than oxidized starches. However, at the low concentrations of depressant used in flotation, oxidized starches were more effective at selectively masking copper sites. This study suggests that a stable chelation between Cu(I) and starch ligands is necessary for depression of copper-activated pyrite at pH 9, which can be achieved with oxidized wheat starch.

在矿石矿物提取的重要过程浮选过程中，淀粉可以理想地吸附和抑制铜活化黄铁矿。为了研究普通小麦淀粉 (NWS) 和高直链小麦淀粉 (HAW)、糊精和一系列氧化普通小麦淀粉对铜活化黄铁矿在 pH 9 下的结构/功能关系、吸附和抑制特性（过氧化物和次氯酸盐处理）进行了调查。吸附等温线和工作台浮选性能与运动粘度、摩尔质量分布、表面覆盖率和取代官能团测定进行了比较。氧化淀粉中摩尔质量分布和取代官能团的差异对铜活化黄铁矿的抑制作用影响不大。然而，引入-C=O和-COOH取代基，与 NWS 和 HAW 相比，结合解聚，提高了溶解性和分散性，减少了聚集结构，并增强了氧化聚合物的表面结合。在高浓度下，HAW、NWS 和糊精比氧化淀粉更多地吸附在黄铁矿表面。然而，在浮选中使用低浓度抑制剂时，氧化淀粉在选择性掩蔽铜位点方面更有效。这项研究表明，Cu(I) 和淀粉配体之间的稳定螯合对于在 pH 9 下抑制铜活化黄铁矿是必要的，这可以通过氧化小麦淀粉来实现。和糊精比氧化淀粉更多地吸附在黄铁矿表面。然而，在浮选中使用低浓度抑制剂时，氧化淀粉在选择性掩蔽铜位点方面更有效。这项研究表明，Cu(I) 和淀粉配体之间的稳定螯合对于在 pH 9 下抑制铜活化黄铁矿是必要的，这可以通过氧化小麦淀粉来实现。和糊精比氧化淀粉更多地吸附在黄铁矿表面。然而，在浮选中使用低浓度抑制剂时，氧化淀粉在选择性掩蔽铜位点方面更有效。这项研究表明，Cu(I) 和淀粉配体之间的稳定螯合对于在 pH 9 下抑制铜活化黄铁矿是必要的，这可以通过氧化小麦淀粉来实现。