A direct method for the determination of fluoride ion in the parts per million range is described. The color reaction of fluoride ion and lanthanum chelate of 3-aminomethylalizarin- N,N-diacetic acid forms the basis for the spectrophotometric method. The intense blue fluoride complex in a mixed solvent system of 16% dimethylformamide- 84% water is stable and independent of pH in the range of 4.6-5.6. Other halogens and common anions do not interfere in the measurements. Interfering ions are removed through ion exchange separations. Results on the determination of fluorine in selected samples are presented.
Proceedings of the Iowa Academy of Science
©1962 Iowa Academy of Science, Inc.
Brunzie, Gerald F. and Pflaum, Ronald T.
"The Direct Spectrophotometric Determination of Fluoride Ion,"
Proceedings of the Iowa Academy of Science, 69(1), 186-193.
Available at: https://scholarworks.uni.edu/pias/vol69/iss1/31