(110a) Processing with Solids in a Liquid-Liquid Extraction Column

The typical liquid-liquid extraction process involves the counter current contact of two immiscible liquid phases in order to affect mass transfer of a specific component from one liquid phase into the other. In some instances, the presence of solids can complicate the separation problem. Most extraction columns cannot tolerate a significant amount of solids, primarily due to material building up on the internals and/or slow settling velocity. In some instances, the solute to be removed is within the solid particles. For these processes, the extraction column must be capable of improving the mass transfer out of the solid particles, which still providing sufficient settling velocity to allow for counter current processing. The KARR^® Reciprocating Plate Column has been proven to handle many different types of slurry feed process, including particulates, crystals, and powders. This paper will present three case studies where pilot plant testing in a KARR^® Column was used to demonstrate the feasibility of extraction processes with significant amounts of solids present and to develop the data required for scale up to commercial columns. For each case, unique test methods were developed and individualized equipment set-ups were installed.