Potassium silicates in soaps

Summary Properties of potassium silicates of interest in regard to their use as a detergent with soaps have been studied. A 40% potassium coconut oil soap can be mixed in all proportions with the comercial 3.3 ratio potassium silicate containing 39.6% solids. The pH's of the silicate solutions vary from 9.6 to 11 at concentrations of most practical interest. The 3.3 ratio silicate increases the pH of a potassium coconut oil soap solution. More suds form when the soap is dissolved in a 0.031% K 2 O·3.3SiO 2 solution than in the same molality of a potassium carbonate solution or in pure water. Quantitative measurements of their suspending action on ilmenite shows that at their optimum concentrations both silicates are more effective than potassium carbonate and almost as good as soap. The maximum effect of soap occurs at a higher concentration than that for the silicates. A mixture of soap and K 2 O·3.3SiO 2 prevents the deposition of ferric oxide pigment on cotton cloth about equally as well as soap alone; this mixture is more effective than soap alone for preventing the deposition of raw umber. Both silicates prevented the deposition of raw umber more effectively than soap alone or soap‐alkali mixtures below 0.1% and are not much less effective above this concentration. Soil removal experiments with a cottonseed oil‐Oil‐dag soil showed that a mixture of K 2 O·3.3SiO 2 and potassium coconut oil soap was about equally as efficient in distilled water and more efficient in 300 p.p.m. hard water than soap alone.