论文部分内容阅读
本文提出了用两个简便、准确并且终点明显的络合滴定来测定有机氟化合物中氟的含量之新方法。硝酸镧试剂测定氟化物中含氟量的适用范围是0.45～7.00毫克;硝酸镨试剂测定氟化物中含氟量的适用范围是0.25～3.50毫克。Cl~-、Br~-、I~-、Mg~(2+)、Sn~(4+)、BO_3~-、BrO_3~-等离子对氟化物中含氟量的测定无干扰;PO_4~(3-)、AsO_4~(3-)离子和H_2O_2使测定结果偏高;Cu~(2+)可用硫脲作掩蔽剂,Al~(3+)可用乙酰丙酮作掩蔽剂。滴定前加入2～3滴乙酰丙酮有很大的好处。本法能适用于有机硅氟化合物中氟的测定,而用于有机硼氟化合物中氟的测定则不能得出满意的结果。
This paper presents a new method to determine the content of fluorine in organofluorine compounds by using two simple, accurate and obvious end-point complexometric titrations. Lanthanum nitrate reagent fluoride content determination of the range of 0.45 ~ 7.00 mg; praseodymium nitrate reagent fluoride content in the fluoride range of 0.25 to 3.50 mg. There was no interference with the determination of fluoride content in Cl_ -, Br ~ -, I ~ -, Mg ~ (2 +), Sn ~ (4 +), BO_3 ~ - and BrO_3 ~ -), AsO_4 ~ (3 -) ions and H_2O_2 make the determination results higher; Cu ~ (2+) can use thiourea as masking agent, Al ~ (3+) can use acetylacetone as masking agent. Titration before adding 2 to 3 drops of acetylacetone has great benefits. This method can be applied to the determination of fluorine in organofluorine compounds, but the determination of fluorine in organofluorine compounds can not give satisfactory results.