Polarographic determination of formaldehyde according to the anodic oxidation wave in alkaline solutions

The polarographic waves of CH2O oxidation in 2-3 M NaOH solutions containing 0.04-0.10 M (+)-tartrate are diffusion controlled: the dependences of limiting current (i(lim)) on the square root of the Hg column height are linear and the temperature coefficient of the limiting current is relative small, i.e., similar to 2 % grad(-1). The anodic waves of CH2O oxidation could be used for analytical purposes, i(lim) is proportional to CH2O concentration in the range 2 x 10(-4)-4 x 10(-3) M. The precision of CH2O determination is typical for DC-polarography. A RSD smaller than 3 % has been obtained for 20-200 mu mol CH2O. The method proposed is suitable for the direct determination of formaldehyde in electroless copper plating solutions containing (+)-tartrate or glycerol as Cu(II) ions ligands.