Synthesis and properties of noncyclic polyether compounds. XV. Noncyclic polyether carriers exhibiting potassium-ion-selective transport through liquid membranes: their structures and cation selectivity

Abstract

The effects of the structure of noncyclic polyethers on potassium-ion-selective transport have been investigated using several synthetic noncyclic polyethers as carriers for transport through liquid membranes. The K + selectivity of a polyether with an oxytrimethylene group instead of an oxyethylene group decreased significantly. The position of the introduced o-phenylene group affects the cation selectivity of the polyethers. A polyether with a quinolyl terminal group exhibits superior K + selectivity to otherwise identical polyethers with naphthyl or n-butyl terminal groups. Also, the selectivity of a polyether with a 2-methylquinolyl terminal group substituted for the quinolyl terminal group increased appreciably. Furthermore, it will be demonstrated that simultaneous separation of two alkali ions (Li + and K +) from an aqueous solution containing Li +, Na + and K + ion species could be carried out successfully using both K + - and Li +-selective carriers.