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矿业上广泛应用活性炭和离子交换树脂从浸出液中萃取金属氰化物。近来已经研究了离子交换膜和纤维作为活性炭和树脂替代品的可能性。本文描述了在批量反应器中细矿石颗粒和多孔吸附剂之间的相互作用。氰化金作为被吸附物质用于检测吸附荆的传质特性的变化。这些变化采用薄膜/表面扩散模型进行评价,评价重点在扩散和平衡参数。包括矿石颗粒侵入吸附剂的试验表明氰化金的吸附图只受活性炭和离子交换树脂的影响。对吸附剂进行的灰化试验、扫描电子显微镜和次级离子质谱计检测证实了这些结果。然而,由于悬浮液中细颗粒引起外部表面的自然堵塞使氰化金向所有吸附剂的扩散受到抑制。通过将预先饱和的吸附剂暴露到悬浮的矿石颗粒中,然后溶解氰化金来得到本结果。堵塞的影响通过引入一个可利用因素在模型中加以考虑。
Extensive use of activated carbon and ion exchange resins in the mining industry extracts metal cyanide from leachate. Recently, the possibility of ion exchange membranes and fibers as a substitute for activated carbon and resins has been studied. This article describes the interactions between fine ore particles and porous adsorbents in batch reactors. Gold cyanide as adsorbed material is used to detect changes in the mass transfer characteristics of the adsorbent. These changes were evaluated using a thin-film / surface-diffusion model, with emphasis on diffusion and equilibrium parameters. Tests involving intrusion of ore particles into the adsorbent show that adsorption of gold cyanide is affected only by activated carbon and ion exchange resins. Ashing tests on adsorbents, scanning electron microscopy and secondary ion mass spectrometry measurements confirmed these results. However, the diffusion of gold cyanide to all adsorbents is inhibited due to the natural blockage of the external surface caused by the fine particles in the suspension. This result is obtained by exposing the pre-saturated adsorbent to suspended ore particles and then dissolving gold cyanide. The impact of blockage is taken into account in the model by introducing a factor of availability.