Ozdemir O, Celik M S, Nickolov Z S, Miller J D
Department of Metallurgical Engineering, University of Utah, 135 S. 1460 E., 412 WBB, Salt Lake City, UT 84112, USA.
J Colloid Interface Sci. 2007 Oct 15;314(2):545-51. doi: 10.1016/j.jcis.2007.05.086. Epub 2007 Jun 8.
Interfacial water structure is a most important parameter that influences the collector adsorption by salt minerals such as borax, potash and trona. According to previous studies, salts can be classified as water structure makers and water structure breakers. Water structure making and breaking properties of salt minerals in their saturated brine solutions are essential to explain their flotation behavior. In this work, water structure making-breaking studies in solutions of carbonate and bicarbonate salts (Na(2)CO(3), K(2)CO(3), NaHCO(3) and NH(4)HCO(3)) in 4 wt% D(2)O in H(2)O mixtures have been performed by FTIR analysis of the OD stretching band. This method reveals a microscopic picture of the water structure making/breaking character of the salts in terms of the hydrogen bonding between the water molecules in solution. The results from the vibrational spectroscopic studies demonstrate that carbonate salts (Na(2)CO(3) and K(2)CO(3)) act as strong structure makers, whereas bicarbonate salts (NaHCO(3) and NH(4)HCO(3)) act as weak structure makers. In addition, the changes in the OD band parameters of carbonate and bicarbonate salt solutions are in agreement with the viscosity characteristics of their solutions.
界面水结构是影响硼砂、钾盐和天然碱等盐类矿物对捕收剂吸附的一个极其重要的参数。根据以往的研究，盐类可分为水结构形成剂和水结构破坏剂。盐类矿物在其饱和盐水溶液中的水结构形成和破坏特性对于解释它们的浮选行为至关重要。在这项工作中，通过对OD伸缩带的傅里叶变换红外光谱（FTIR）分析，对碳酸和碳酸氢盐（Na₂CO₃、K₂CO₃、NaHCO₃和NH₄HCO₃）在H₂O中4 wt% D₂O混合物溶液中的水结构形成-破坏进行了研究。该方法从溶液中水分子间的氢键角度揭示了盐类水结构形成/破坏特性的微观图像。振动光谱研究结果表明，碳酸盐（Na₂CO₃和K₂CO₃）是强结构形成剂，而碳酸氢盐（NaHCO₃和NH₄HCO₃）是弱结构形成剂。此外，碳酸和碳酸氢盐溶液的OD带参数变化与其溶液的粘度特性一致。
