K2B4O7和KBO2溶液pH和拉曼光谱研究

Raman Spectroscopic and pH Investigation of Aqueous K2B407 and KB02 Solutions

中文关键词:  四硼酸钾  偏硼酸钾  pH  拉曼光谱

英文关键词:pH

中文摘要:

      用合成的水合四硼酸钾和偏硼酸钾晶体,配制一系列溶液,研究了pH与浓度变化的关系,并计算硼酸根离子的摩尔分数-浓度（δ-c）关系图。用拉曼光谱方法研究四硼酸钾和偏硼酸钾溶液,给出其拉曼光谱图,并对各峰进行了归属。研究表明,四硼酸钾溶液中存在的物种主要有[B4O5（OH）4]2-、[B3O3（OH）4]-和[B（OH）4]-,而其它物种所占摩尔分数很小;在偏硼酸钾水溶液中,[B（OH）4]-占绝大多数,有很少量H3BO3、[B4O5（OH）4]2-和[B3O3（OH）4]3-。硼酸盐离子浓度越低,越容易水解为聚合度较低的简单物种。

英文摘要:

      Potassium tetraborate and potassium metaborate crystals were synthesized and a series of borate solutions were prepared.The relationship between concentration and pH was studied,and the mole fraction of borate anions and the corresponding concertration（δ-c） were also given.A detailed investigation of aqueous potassium borate and potassium borate solutions has been performed by Raman spectroscopy.Assignments of the bands were tentatively ascribed.The results reveal that the main species are [B4O5（OH）4]-,[B3O3（OH）4]-and [B（OH）4]-in aqueous potassium tetraborate solution,while other species＇ amounts are so small that can be neglected.In potassium metaborate solutions,[B（OH）4]2-is the majority,other species such as H3BO3,[B4O5（OH）4]2-and [B3O3（OH）4]-extremely tiny.The concentration of borate anions is,the more a simple species of low degree polymerization would be produced.