Influence of Mg, Ca, Fe, Cu and Zn Ions on static surface tension of surfactant solutions

摘要

The objective of this study was to evaluate the influence of 5 ions on a spray solution containing the surfactant aterbane. Surface tension was analyzed by measuring the mass of a set of 25 drops, with four repetitions constituting a treatment. The work was divided in two stages. In the first, the treatments were arranged in a 9x5x2 factorial design, nine Aterbane concentrations (0.01; 0.025; 0.05; 0.1; 0.2; 0.5; 1; 2; and 3%) and five ions (Mg++, Ca++, Fe+++, Cu+++ and Zn+++) at 2 concentrations (10 and 100 ppm). In the second stage, the treatments were arranged in a 5x5x1 factorial design using the same five elements (Mg++, Ca++, Fe+++, Cu+++ and Zn+++) at 5 concentrations (1, 5, 20, 50 and 100 ppm) with only one surfactant concentration (0.025%). Nine other treatments allowed to evaluate the surface tensions of the surfactant concentrations without ion addition. The results showed that the ions interfered in the solutions, except for Fe (at concentration of 10 and 100 ppm) and Cu (at concentration of 100 ppm), since all ions reduced the minimum tension reached and increased surfactant effectiveness, enhancing surfactant action and the characteristics of possible application solutions. All ions evaluated reduced the surface tensions of the surfactant solutions at a concentration of 0.025%.