弱碱环境下羧甲基壳聚糖对石英/钾长石浮选抑制性能的影响

Effect of Carboxymethyl Chitosan on the Depression Performance of Quartz/K-Feldspar Flotation under Weakly Alkaline Condition

石英和钾长石属于性质接近的共伴生硅酸盐矿物,为改善石英常规浮选酸浸废液污染严重和常规捕收剂十二胺泡沫量过大不利于浮选的问题,在新型二胺类捕收剂体系下通过纯矿物浮选探究了羧甲基壳聚糖在弱碱性环境下对石英及钾长石浮选的抑制效果,同时通过Zeta电位测试、红外光谱(FTIR)和X射线光电子能谱(XPS)对产生吸附的主要机制进行了分析。纯矿物浮选对比了2种二胺类捕收剂的效果,其中1,10-二氨基癸烷(DAM)的捕收性能优于1,8-辛二胺(ODM);在p H=9、捕收剂DAM用量为20 mg/L的条件下,120 mg/L的羧甲基壳聚糖可对石英/钾长石体系中的石英产生有效抑制,此时回收率差异可达约52个百分点,人工混合矿浮选结果也证明了羧甲基壳聚糖可有效分离石英和钾长石。机理分析结果表明,羧甲基壳聚糖表面水解产生的多级胺基基团通过氢键作用吸附在石英表面,同时大量羧基吸附大幅提升了石英表面亲水性,实现了无酸环境下石英和钾长石的有效分离。

Quartz and K-feldspar are co-associated silicate minerals characterized by similar properties.In order to mitigate the environmental impact of acid leaching effluents associated with quartz flotation and the large amount of bubbles by the conventional collector dodecylamine not conducive to flotation,the depression effect of carboxymethyl chitosan on flotation of quartz and K-feldspar in weak alkaline environment was investigated by pure mineral flotation under the novel diamine collector system.The main mechanism of adsorption was analyzed by Zeta potential test,Fourier Transform Infrared Spectroscopy(FTIR)and X-ray photoelectron spectroscopy(XPS).Comparative analysis of the flotation performance of two diamine collectors revealed that 1,10-diamino-decane(DAM)outperforms 1,8-octamethylene diamine(ODM).Specifically,under conditions of pH of 9 and DAM dosage of 20 mg/L,the addition of 120 mg/L CMC effectively suppresses quartz flotation within the quartz/K-feldspar system,resulting in a recovery difference of up to about 52 percentage points,the results of artificial ore mixing also prove that carboxymethyl chitosan can effectively separate quartz and K-feldspar.Mechanism analysis results showed that the multistage amine groups produced by carboxymethyl chitosan surface hydrolysis are adsorbed on the quartz surface through hydrogen bonding.This adsorption significantly enhances the hydrophilicity of the quartz surface,thereby facilitating the effective separation of quartz and K-feldspar in an acid-free environment.