论文部分内容阅读
卵清蛋白(OVA),俗称鸡卵清白蛋白,是一种环保、无毒、廉价的表面活性剂。它的分子结构中含有电化学活性巯基。采用循环伏安法、红外光谱和浮选实验研究OVA在黄铁矿表面吸附以作为替代抑制剂。在宽的电位范围内和碱性pH值条件下,研究电化学条件对吸附机制和抑制率的作用。当OVA不存在时,可浮性在弱氧化电位条件下达到极大值。超出此电位范围,可浮性会由于生成Fe的氢氧化物以及亲水类的硫化物而降低。在整个测试电位范围内OVA黄铁矿发生相互作用。OVA的抑制效果随着电位从还原电位、弱氧化电位,到黄铁矿的开路电位逐渐增加,这主要是由于OVA分子弱的构象变化以及开路电位下的疏水作用引起的。OVA的抑制率在中等氧化电位下达到极大值,这被称为静电引力。由于OVA以金属螯合物形式吸附,在较高的电位下这种高的抑制效果可以几乎一直保持下去。
Ovalbumin (OVA), commonly known as chicken egg white albumin, is an environmentally friendly, non-toxic, inexpensive surfactant. Its molecular structure contains an electrochemically active thiol group. Cyclic voltammetry, infrared spectroscopy and flotation experiments were used to study the adsorption of OVA on pyrite surface as an alternative inhibitor. The effects of electrochemical conditions on the mechanism of adsorption and inhibition were investigated over a wide potential range and at alkaline pH. When OVA is absent, floatability reaches a maximum under weak oxidizing potential conditions. Beyond this potential range, floatability is reduced by the formation of hydroxides of Fe and hydrophilic sulfides. OVA pyrite interacts throughout the test potential range. The inhibitory effect of OVA gradually increases with the potential from the reduction potential to the weak oxidation potential to the open circuit potential of pyrite, which is mainly due to the weak conformational change of OVA molecule and the hydrophobic effect under the open circuit potential. The inhibition rate of OVA reached a maximum at a moderate oxidation potential, which is called electrostatic attraction. Since OVA is adsorbed as a metal chelate, this high inhibitory effect can be maintained almost continuously at higher potentials.