Determination of trace amount of nickel carbonyl in air

Abstract

Nickel carbonyl is heavily toxic and is said that its allowable limits are 3 ppm (by volume) for 30 minutes exposure, 40 ppb for 40 hours and 1ppb in ordinary working circumstance.
An attempt has been made by the authors to obtain an accurate and rapid method of determination of nickel carbonyl, and the following method is presented. Add 20 ml of iodin-ethyl alcohol soln. (0.05%) in a specially designed absorption tube, dip it in a trichloroethylene-dryice cooler of -30°C and then pass sample air through it at the rate of 2 l/min. Dry up the absorption solution on a sand bath, dissolve the black residue of nickel iodate in water and determine the nickel colorimetrically as dimethylglyoxime complex. Nickel carbonyl in ppb order can be determined by using 500 l air and the time required is 67 hours.
The proposed method is more accurate and rapid than the conventional methods in practice.