A systematic study on the determination of optimal transport conditions for methylene blue using new generation Pillar[5]arene-based bulk liquid membrane in aqueous phase

Most of the dyes are toxic chemicals with mutagenic and carcinogenic effects on humans and need to be purified from water and other sources. Therefore, new substances with high selectivity towards these substances' discovery is very important. In this paper, a pillar[5]arene derivative including ten iodine moieties, the newest member of macrocycles, was synthesized and used for the removal of methylene blue (MB) using a bulk liquid membrane system and named P[5]-iodine. The synthesized Pillar[5]arene derivative was characterized by using of various techniques, NMR, FT-IR, elemental analysis, melting point etc. The optimum conditions for the transport process were experimentally determined that the pH of the donor phase and acceptor phase as 6 and 3, respectively. The experimental results showed that the pillar[5]arene carried efficiently to MB at 298 K by using dichloromethane as a solvent in 10-3 M and 10-4 M concentrations for the membrane and the donor phase, respectively. The best transporting of MB as a cationic dye toward water (complexing between membrane/ donor) was carried out under the optimum conditions that pH is the most important of the parameters examined as a driving force. The kinetic parameters and activation energies were calculated at various temperatures. The activation energies (Ea1: 2.69 kcal/mol, Ea2: 7.66 kcal/mol) indicate effective and feasible transport mechanisms. As result, the prepared Bulk Liquid Membrane/P[5]-iodine hybrid system has a highly sensitivity in the transport of MB.