2.5.3. Transport Experiments

Transport was investigated using 50 mL of SNW spiked with 100 μg L⁻¹ As(V) or 300 μg L⁻¹ P(V) as a feed solution and 2.5 mL of 2 M NaCl as the receiving (or stripping) phase. A device previously described by Fontàs et al. was used [36]. The NP-PIM was placed at the bottom of the device contacting the feed phase while the receiving solution was placed inside the compartment. The transport and preconcentration of anionic species occurs through the NP-PIM from the feed phase to the receiving phase.

Transport efficiency (TE%) was determined by using Equation (3):

where C_strip,t denotes the As or P concentration in the receiving compartment at an elapsed time t and C_feed,0 is the initial As or P concentration in the feed phase, both measured by ICP-OES. V_feed and V_strip are the volumes of the solutions in the respective compartments.