Extraction and carrier mediated transport of urea using noncyclic receptors through liquid membrane systems

Extraction and carrier mediated transport through bulk liquid membrane and supported liquid membrane systems have wide applications in separation technology. This paper highlights the use of six noncyclic receptors (podands) having variations in chain length and end group for the removal of urea using liquid membrane system. These receptors R-1, R-2, R-3, R-4, R-5, R-6 are diethylene glycol dimethyl ether, diethylene glycol dibutyl ether, diethylene glycol dibenzoate, diethylene glycol, triethylene glycol and tetraethylene glycol respectively. The sequence of extraction and transport of urea by BLM system using various receptors is R-2 > R-3 > R-1 > R-4 > R-5 > R-6 and R-6 approximate to R-3 > R-5 > R-4 > R-1 > R-2 respectively. Receptor R-2 containing butyl end group is best extractant while receptor R-6 with flexible backbone is best carrier and this carrier efficiency is used to remove urea using BLM system from the feed phase by recyclization process up to 88.16%. The experimental results influenced by concentration of receptors and urea. Effect of time was also studied. (C) 2019 The Authors. Published by Elsevier B.V. on behalf of King Saud University.