Abstract
Industrial vinyl acetate usually contains, as the impurities, minute amounts of acetaldehyde, crotonaldehyde, methyl acetate, acetone, methanol and benzene. Gaschromatographic determination of these impurities has been investigated by the authors.
Acetaldehyde, methanol, acetone and methyl acetate in vinyl acetate can be determined separately by using a column of DM-13A with silicone oil DC-510 (85%) and stearic acid (15%) (column No. 1). The lower limit of detection is 0.006vol% for acetaldehyde, 0. 007vol% for methanol, 0.015vol% for acetone, and 0.018vol% for methyl acetate. The peak of methanol by the column No. 1 is disturbed by the peaks of water and acetaldehyde when vinyl acetate contains Comparative qantity of water and acetaldehyde, while methanol can be separately determined by using a column of DM-13A with glycerin (column No. 2) even when much water and acetaldehyde are contained in the sample. The determination of crotonaldehyde is also possible by the 2nd column. The lower limit of detection is 0.031 vol% for crotonaldehyde, and 0.013vol% for methanol. Benzene can be determined by using a combination of the 1st and 2nd columns, the limit of detection being 0. 024vol%.
