Flow injection analysis for boron determination by using methyl borate generation and flame atomic emission spectrometry

Boron is one of the least sensitive elements in atomic emission spectrometr y. As various refractory substances interfere in the analysis and because o f the low sensitivity, sample enrichment and the separation of the interfer ing matrix is needed. Methyl borate has many advantages because of its simp le generation conditions and its stability in the absence of moisture. New procedures for the generation of methyl borate without using external heati ng have also been investigated to produce a more rapid determination of bor on. The on-line combination of flow injection analysis using methyl borate gene ration with flame atomic emission spectrometry as the detector is proposed to provide sufficient enrichment factors in order to determine boron in dif ferent matrices. In order to obtain as much moisture-free medium as possible, all standard s olutions were prepared in 60% H2SO4 (v/v) according to the experimental res ults. The effect of Ar flow rate, peristaltic pump rate, size of the tubing s used, and length of the mixing coil to the emission signal were all studi ed. Furthermore, the design of the gas liquid separator, and several ways t o transfer the signal to AES were also examined in detail. A linear calibra tion graph was obtained between 10 and 2000 mug/mL with the equation y = 0. 1105X - 1.496. The detection limit of the method was calculated as (3S) 2.9 6 mug/mL or 0.74 mug B.