Transport of K+ from Seawater Using Dibenzo-l8-crown-6 via Carbon Nanotube Based Pseudo Supported Liquid Membrane

In the present study, the transport of potassium salt as an important agricultural fertilizer is reported through a pseudo carbon nanotube supported liquid membrane using dibenzo-l8-crown-6 as the carrier. Single wall carbon nanotube was utilized as an additive to liquid membrane to form a pseudo support, while the extraction result showed a noticeable increase in the process rate. In order to find the best transport conditions, affecting parameters such as the feed pH and receiving phases, type of membrane solvent, concentration of the carrier, stripping solution conditions, time, and temperature were investigated. In the optimum working conditions and after 80 min, 23.0(±0.1) % of K+ from the feed phase (containing K+ = 0.01 M, NaCl = 0.01 M, pH = 5.6) across a dichloromethane membrane (DB18C6 = 0.01 M) was transported into the receiving phase (containing HCl 1 M and NaCl = 0.01 M). The selectivity of the method was evaluated by performing the competitive transport experiments on the simulated mixtures containing the main ions with conservative concentration of seawater.