Selective transport of copper(II) ions across a liquid membrane mediated by Piroxicam

摘要

Piroxicam was found to be a highly selective carrier for uphill transport of Cu2+ ions through a chloroform liquid membrane. The transport occurs via a counterflow of protons from the receiving phase to the source phase. The effects of several parameters on the transport of Cu2+ ions, such as the carrier concentration, pH of the source phase, composition of the receiving phase, and duration are described. A high transport efficiency (98±2%) was provided by the carrier for Cu2+ ions in a receiving phase of 0.01 mol l−1 sulfuric acid after 4 h. Different metal ion transport experiments showed that Cu2+ ions were selectively transported over other ions, such as Co2+, Ni2+, Cd2+, Pb2+, Zn2+, UO 2 2+ and ZrO 2 2+ . In the presence of fluoride ions (used as a suitable masking agent in the source phase), the interfering effects of UO 2 2+ and ZrO 2 2+ ions were eliminated. The applicability of the method was tested on a real sample, and the results obtained show that it is potentially useful for solvent extraction of copper.