拉曼积分球光谱仪对盐水溶液中B(OH)3的定量分析

Quantitative Analysis of Boric Acid ( B(OH)3 ) in Aqueous Salt Solution by Simplified Raman Integrating Sphere

中文关键词:  拉曼积分球  定量  硼酸  盐水溶液

英文关键词:Simplified Raman integrating sphere  Quantitative analysis  Boric acid  Aqueous salt solution

中文摘要:

      不同溶液体系中硼的赋存形态及其化学分布规律一直以来是研究者关注的重点，它对深入开展硼酸盐溶液结构化学、过饱和非平衡态以及硼酸盐矿物沉积机制等研究具有重要的指导意义。针对目前拉曼光谱仪对溶液中硼氧配阴离子官能团响应信号弱、灵敏度低，不利于定量化视角阐述硼氧配阴离子间的作用机理等问题。本文研究了拉曼积分球光谱仪对硼酸溶液的定量分析方法，运用DOE部分因子实验设计，阐述了NaCl、MgCl2、KCl和MgSO4等共存盐类之间的交互作用对B(OH)3拉曼定量分析的影响规律，建立了盐水溶液中B(OH)3的Raman回归模型。结果表明，拉曼积分球光谱仪可显著增大硼酸溶液的拉曼光谱强度，提高信噪比，检出限为常规拉曼光谱的70倍，在0 ~ 6 g?L-1硼酸线性范围内相关系数为0.9991，测定相对误差为-2.5%；盐水溶液中B(OH)3含量经回归方程校正后相对误差绝对值小于3%，可用于低浓度硼酸的准确定量分析，也为定量化探究盐卤复杂体系中多硼物种化学形态分布规律提供一定借鉴。

英文摘要:

      Study on borate species and their distributions in aqueous solution are of great importance for the borate structure and thermodynamic non-equilibrium in aqueous solution and also borate deposits in salt lake, which has drew more and more attention to recent researchers. Aiming at improving the weak signal and low sensitivity of Raman characterization for borate species in aqueous solution, which is beneficial to analyze the interaction among borate anions in the quantitative perspective, this study has investigated the boric acid quantity in aqueous salt solution by using simplified Raman integrating sphere. The interaction effects of coexisting salts of NaCl, MgCl2, KCl and MgSO4 on Raman quantitative analysis of boric acid have been studied and the regression equation of boric acid has also been proposed. The results showed that the simplified Raman integrating sphere can significantly increase the Raman spectrum intensity of boric acid in aqueous solution. The corresponding limit of detection is about 70 times much higher than the conventional Raman spectroscopy. The correlation coefficients is more than 0.9991 in the range of 0 ~ 6 g?L-1 of boric acid. And the relative error of measurement is about -2.5%. In the salt solution system of NaCl-MgCl2-KCl-MgSO4, The absolute value of relative error is less than 3% after corrected by the regression equation, which can be applied in the low content measurement of boric acid. The results of this paper could provide fundamental information and theoretical guidance for the future exploration of the quantitative analysis of the borate speciation in the brine.