Abstract Although available flotation experiments show that sulphide flotation recovery increases with increasing xanthate chain length, quantitative analysis to reveal the underlying mechanisms is missing. Herein, we investigate the chain length effect by using a recently developed attachment apparatus and an advanced theory to determine and validate the attachment time of air bubbles to galena surfaces in solutions of ethyl, propyl, butyl and amyl xanthate collectors. Specifically, the attachment time was accurately determined from either transient force curves or transient film thickness of the bubble-surface attachment. The theory was based on the film drainage theory and colloidal forces, which include the advanced multilayer dispersion (van der Waals) interactions and the electrical double-layer interaction. The multilayer dispersion theory has allowed us to describe the effect of galena hydrophobicity induced by the xanthate chain length in terms of interfacial gas enrichment (IGE) on the bubble-surface attachment. The experimental results show that the attachment time is greatly affected by both the hydrophobicity and the bubble size, and agree with the theoretical results. Critically, it was possible to accurately quantify the attachment time of the hydrophobised galena surfaces to bubbles using the measured transient force curves and the advanced multilayer dispersion theory incorporating the IGE layer. Finally, this study made it possible to explain the effect of the hydrophobicity and bubble size on attachment time and provides the principle for the attachment mechanism of hydrophobic minerals to air bubbles.

中文翻译：

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黄药链长度对方铅矿表面气泡附着的影响的测量和分析

摘要 尽管现有的浮选实验表明硫化物浮选回收率随着黄药链长度的增加而增加，但缺少揭示潜在机制的定量分析。在此，我们通过使用最近开发的附着装置和先进的理论来研究链长效应，以确定和验证气泡在乙基、丙基、丁基和戊基黄原酸收集剂溶液中的方铅矿表面的附着时间。具体来说，附着时间是根据气泡表面附着的瞬态力曲线或瞬态膜厚度准确确定的。该理论基于薄膜排水理论和胶体力，其中包括高级多层分散（范德华）相互作用和双电层相互作用。多层分散理论使我们能够从界面气体富集 (IGE) 对气泡表面附着的角度来描述由黄药链长度引起的方铅矿疏水性的影响。实验结果表明，附着时间受疏水性和气泡大小的影响很大，与理论结果一致。至关重要的是，可以使用测量的瞬态力曲线和结合 IGE 层的先进多层分散理论来准确量化疏水化方铅矿表面与气泡的附着时间。最后，这项研究使得解释疏水性和气泡大小对附着时间的影响成为可能，并为疏水性矿物对气泡的附着机制提供了原理。