Surface activity of foam fractions of a calcium lignosulphonate

Successive foam fractionation has been used to divide a processed calcium lignosulphonate into tractions differing appreciably in surface activity. Static surface tension has been measured by the de Nouy tensiometer and surface tension aging by the sessile bubble (photographic) method. The effect of concentration on surface tension has been determined. The effect of pH at 1% concentration on dynamic surface tension has been determined on freshly prepared solutions.