Dissolution of Soap Scum by Surfactant. Part II: Effects of NaCl and Added Chelant on Equilibrium Solubility and Dissolution Rate of Calcium Soap Scum in Amphoteric Surfactant Solutions. Issue 5 (29th March 2014)

• Record Type: Journal Article
• Authors: Itsadanont, Sawwalak; Ratanalert, Darunrat; Soontravanich, Sukhwan; Scamehorn, John F.; Sabatini, David A.; Chavadej, Sumaeth
• Is Part Of: Journal of surfactants and detergents. Volume 17:Issue 5(2014)
• Page Start: 859
• Page End: 864
• Publication Date: 2014-03-29
• Subjects: Soap scum solubility -- Soap scum dissolution rate -- Amphoteric surfactant -- Chelant; Surface active agents -- Periodicals; Detergents -- Periodicals; 668.1
• DOI: 10.1007/s11743-014-1583-4
• Languages: English
• ISSNs: 1097-3958

Abstract

Abstract: The effects of solution pH and NaCl on the equilibrium solubility and dissolution rate of a model soap scum (calcium octadecanoate or calcium stearate) in aqueous solutions of dimethyldodecylamine oxide surfactant (DDAO) with and without chelant disodium ethylenediaminetetraacetate are reported. The equilibrium solubility and dissolution rate of soap scum increased with increasing solution pH when the chelant was added in the DDAO system while in the chelant‐free systems the opposite trend was observed. The added NaCl has an ambiguous effect on the solubility and dissolution rate of soap scum in the absence of chelant, but a small level of added NaCl reduces both solubility and the dissolution rate constant in the presence of chelant. Both equilibrium and kinetics of dissolution are maximized at high pH with DDAO/chelant and no added salt.