Determination of ultratrace amounts of boron in high purity alcohols by inductively coupled plasma-mass spectrometry with hydrofluoric acid potassium fluoride treatment

A simple method for the determination of ultratrace amounts of boron in methanol, ethanol, l-propanol, and 2-propanol is proposed. In the pretreatment procedure, 1.0 mi of the 22 M hydrofluoric acid (HF) solution, 20 mu l of a 1 mg/ml K+ (KF) solution, and 40 g of the alcohol sample were taken in a platinum dish. The mixed solution was then evaporated to dryness on a water bath in a PTFE (polytetrafluoroethylene) cover purged with 2 l/min N-2. After finishing the evaporation to dryness, the residue on the bottom of the platinum dish was dissolved in 3.0 mi of 0.5 M hydrochloric acid (HCl) solution, and the boron concentration was measured by inductively coupled plasma-mass spectrometry (ICP-MS) with pneumatic nebulization. The analytical detection limit of the present method was 3 pg/g as the alcohol weight basis. The method was applied to the determination of boron in the various alcohol samples. According to the analytical results of boron in the alcohol samples examined, it was found that the concentrations of boron were in the range of ng/g-pg/g. (C) 1998 Elsevier Science B.V. All rights reserved.