Development of method for boron determination in basalt fibers

Abstract

The main objective of the present thesis was to develop a method to determine the boron content of boron doped basalt fibers. Two types of samples were investigated: natural basalt powders doped with H3BO3 were used for method development and the method was applied to basalt fiber samples from two different fiber producers. Na2O2 based alkaline fusion with different sample masses and the use of HCl and HNO3 for dissolution of fusion residues was investigated. The results show that using 10:1 flux to sample ratio and HCl as dissolving acid allows for full digestion of sample and determination of boron content by MP-AES analysis. Results from the analysis of commercial basalt fibers revealed that fibers from one producer, contrary to the suppliers claim, did not contain any boron, highlighting the need for quality check and the development of method to do that.