Liquid-liquid extraction and separation of barium from associated elements using dibenzo-24-crown-8

Environmental Analytical Chemistry Laboratory, Department of Chemistry, Shivaji University, Kolhapur-416 004, India

Manuscript received 13 September 1999, revised 14 February 2000, accepted 28 April 2000

A simple extractive separation method for trace level of barium (2.5-25 ppm) has been developed using dibenzo-24-crown-8 from picric acid medium. Barium is quantitatively extracted from 0.008-0.05 M picric acid with 0.0008-0.01 M dibenzo-24-crown-8 in nitrobenzene as a diluent. From the organic phase barium is quantitatively stripped with 1-10 M HNO₃ and HCIO_4, 1-8 M HBr, 0.1-2.0 M HCI. Separation of barium has been carried out from a number of binary and multicomponent mixtures. The method is extended for the determination of barium in various rock samples.