Abstract
The desorption of surfactant from carbon black suspension was studied as a function of time by using the stopped flow method. The surfactants used were sodium decyl sulfate (SDeS), sodium dodecyl sulfate (SDS), and sodium tetradecyl sulfate (STS). Carbon black suspensions containing various concentrations of surfactants were rapidly diluted with distilled water by using a mixing cell with two syringes. The electric conductivity of suspension increased with time due to the liberation of surfactant from carbon black. The changes in conductance with time were monitored by a conductmeter and an oscilloscope connected with it. The rate constants of desorption were estimated from results by applying the first-order reaction scheme. The rate constants in early stage of desorption process thus obtained were 1.8, 0.8, and 0.6s-1. for SDeS, SDS, and STS, respectively. Their half life periods were estimated to be 0.41.2s from the rate constants.
