The determination of fluorides in preservative-treated spruce and redwood

Abstract

A method is described for the rapid determination of fluoride in wood that has been treated with preservatives containing sodium fluoride or potassium hydrogen difluoride. The fluoride is leached from thin sections of wood with sodium hydroxide solution and determined by spectrophotometric measurement of the blue complex formed between fluoride ions and the red lanthanum chelate of alizarin fluorine blue.

The procedure is particularly useful for the study of the distribution of fluoride-containing preservatives in wood.