Thin layer extraction—A novel liquid–liquid extraction method



The overall task of a liquid–liquid extraction process consists of selectively transferring solutes from a donor solution to a recipient solution through a liquid extractant, with the purpose of purifying the donor solution and/or recovering a valuable solute. Thin layer extraction (TLX) is a novel method to carry out this task, using specialized equipment and temporal modes of operation. In TLX, a minute amount of an extractant that is firmly attached as thin layer to a solid substrate is intimately and frequently brought into contact alternately with the donor and recipient solutions. TLX incorporates the complete extraction/stripping scheme into one single device. Following presentation of the underlying concepts, the structural, design, and operational aspects are discussed. TLX is applicable on a wide range of scales and can be easily scaled up to production floor size or down to the microscale. It has inherent operational, safety, and environmental qualities. © 2008 American Institute of Chemical Engineers AIChE J, 2008