Flotation behavior and mechanism of rutile with nonyl hydroxamic acid

The flotation and surface interaction of rutile with nonyl hydroxamic acid were investigated in this work. The results show that the adsorption density and flotation recovery of rutile have similar tendency, especially the maximum recovery and adsorption occur at pH about 7.5. In terms of Fourier transform infrared（FTIR） spectroscopic analysis, chemical adsorption is identified on the surface of rutile, where a chelate of O,O-five-membered rings with Ti^4＋ on the surface of rutile may form. Adsorption measurements, Zeta potential test, IR spectrum analyses, and solution chemistry calculations illustrate that the adsorption on the rutile surface involves both physical and chemical adsorption, while chemical adsorption is dominant.

γ-羟基壬基羟肟酸和壬基羟肟酸对孔雀石的浮选性能及吸附机理研究

为了发现-OH改性后壬基羟肟酸的物理性能、浮选性能和吸附机理的变化情况,本文通过单矿物浮选试验、红外(FT-IR)和X射线光电子能谱(XPS)表征手段,开展了γ-羟基壬基羟肟酸(HNHA)和壬基羟肟酸(NHA)对孔雀石的物化性质、浮选性能及吸附机理研究。NHA常温为固态,经过羟基改性后,HNHA的熔点降低并表现为液态,pKa由7.99降低至7.89和logP由2.37降低至1.14。浮选对比试验结果表明,低用量时HNHA的捕收能力弱于NHA且最佳浮选值不一样。药剂用量为70mg/L时,HNHA和NHA分别在pH=6和8对孔雀石的回收率达到最大值,其HNHA的回收率为72.5%,NHA为79.5%。当药剂用量大于150mg/L时,两者对于孔雀石的回收率相近,接近96%。FTIR和XPS表征结果表明,两种羟肟酸均以C-O-Cu和N-O-Cu的键合方式固定在矿物表面,γ位上的OH并未参与成键。