Using a 5/8" Diameter KARR Column for Generating Scale up Data

The design of liquid-liquid extraction (LLE) columns is best achieved via pilot plant testing followed by scale-up using proven empirical correlations. This method allows the design engineer to determine the size for the production column with a high degree of confidence since it is based upon actual operating data. Therefore the smallest diameter pilot scale column that can accurately generate data has the obvious benefit of requiring less feed and solvent materials for testing. For many years, the KARR® Column has been designed via testing in a 1” (25 mm) diameter, glass-shell, pilot column. A study has been underway to develop comparison data between a 5/8” (15 mm) diameter column and the 1” diameter column. Two (2) previous papers covered testing with high interfacial tension systems. This paper presents data generated for the system of ethyl acetate – acetic acid – water, which is a lower interfacial tension system. A comparison is made between the 1” and 5/8” diameter KARR® Columns with regards to capacity, efficiency, and agitation speed. Based upon this work, the potential for using the 5/8” diameter column for generated accurate scale up data is discussed.