Spectrophotometric Determination of Sodium Dodecylsulfate in Wastewater Based on Ion-Pair Extraction with Safranine-O

In the present work, a simple and relatively fast spectrophotometric method was developed for the determination of sodium dodecylsulfate in wastewater based on the formation of an ion-pair, surfactant-Safranin-O (SDS-SO). Parameters such as type and concentration of counter ion, shaking time, type of organic solvents, type of inorganic acid, and pH of aqueous phase, which affect extraction efficiency, were studied and optimized. Under the optimal experiment conditions, the method exhibited a wide linear range (0.3–17.0 μM) with detection limit of 0.2 μM. Analytical accuracy and precisions, determined from replicate (n=6) analysis of spiked laboratory standards, were in the range of 91 to 106 % and lower than 1.6 %, respectively.