Separation and preconcentration of strontium from calcium in aqueous samples by supported liquid membrane containing crown ether

Supported liquid membrane containing crown ether (DC18C6) and dinonylnaphth alenesulfonic acid (DNNS) is proposed for separation and preconcentration o f strontium in an aqueous environmental sample. The effects of carriers in membrane on permeability and selectivity of Sr2+ were characterized. Crown ether has a key role in the selective transport of strontium ion while DNNS facilitates the transport of both Sr2+ and Ca2+. A strontium ion can be se lectively transported to an acidic strip solution against its concentration gradient across the membrane. This SLM can be used as an efficient method for separation and preconcentration of strontium in a neutral aqueous sampl e.