Transport of Cr(Ⅵ) using an advanced membrane technology and (PJMTH~+NO_3~-) ionic liquid derived from amine Primene JMT as green chemicals

摘要

The extraction of Cr(Ⅵ) from acidic solutions through pseudo-emulsion-based membrane strip dispersion (PEMSD) was conducted in a microporous hydrophobic polyvinylidenediflu-oride (PVDF) membrane support and permeation cell. As organic extractant ionic liquids derived from the primary amine Primene JMT in cumene was used. The acidic feed solution containing Cr(Ⅵ) was placed in one side of the permeation cell, whereas the pseudo-emulsion of Primene JMT/cumene and acidic solution was placed in the other side of the cell, using a single microporous hydrophobic PVDF membrane support for extraction and stripping. In PEMSD the aqueous acidic (HNO_3) solution was dispersed into the organic (Primene JMT/cumene) membrane solution with a mixing arrangement (impeller stirrer) designed to form a strip dispersion. This operation mode provides a constant supply of the ionic liquid extractant/cumene solution to the membrane pores. Various hydrodynamic and chemical parameters, either in the feed or in the pseudo-emulsion phases, were investigated. Results showed that from feed solutions in the pH 3 range, chromium removal efficiencies exceeding 90% are achieving after 3h, whereas chromium recovery in the strip solution is dependent upon the strippant concentration. Furthermore, the performance of this carrier against other extractants was evaluated.