Abstract
In order to use protein as a chemical to bring about effective foam separation, it is necessary to understand foaming capacity and the factors that affect this capacity. In this study, the effect of various protein solutions on foaming capacity were measured using a bubbling column. The test compounds were casein, soy protein, albumin, hemoglobin, gelatin, and LAS.
The foaming capacity of a protein and a surfactant were evaluated by determining the height of the foam at the time of splitting or decaying within the bubbling column under constant conditions of air flow, volume of test solution, and water temperature. The most effective protein was casein followed by hemoglobin, soy protein, gelatin, and albumin. The capacity of casein was comparable to that of LAS. Under appropriate conditions, 0.3l-air · min-1, 100ml sample, 20°C, and pH6.9, the concentrations of casein and LAS required to make a foam height of 30cm (column diameter, 2.6cm) were 4.4mg · l-1 and 4.6mg · l-1, respectively.
