Mass Transfer Studies on Ternary Systems in a Bench-scale Liquid-Liquid Extraction (LLX) Column and a Comparison with Simulations

摘要

Mass transfer studies in a laboratory scale extraction column have been conducted for Toluene-Acetone-Water and MIBK-Acetic Acid-Water systems. From these experiments stage-wise solute (Acetone or Acetic-Acid) composition profiles have been obtained for both dispersed and continuous phase. These composition profiles have been compared with those obtained from ASPENPLUS, CHEMSEP and LLXSIM simulators. For liquid-liquid equilibrium calculations all these simulators use UNIFAC and UNIQUAC model. The binary interaction parameters for the UNIFAC are inbuilt in ASPENPLUS and CHEMSEP. UNIQUAC binary parameters were borrowed from DECHEMA. Error square analysis indicates that simulations based on non-equilibrium option of LLXSIM match closely with experimental results. Temperature profiles and hydrodynamic features characterized by number of drops and static holdup on the stages have been compared between the LLXSIM simulated and the experimental results and these match well. However simulations on ASPENPLUS give sum of relative error-squares for all the experimental runs at least ten times higher, in spite of tuning the average stage efficiency.