The Correlation for Effective Distribution Coefficient with Initial Impurity Concentration and Growth Rate for Acrylic Acid in Melt Crystallization

The layer growth rates and resulting crystal purity during solid-layer melt crystallization were experimentally measured for acrylic acid (AA) with impurity propionic acid (PA) operated at various cooling temperatures. A power law was adopted to correlate the growth rate with the temperature difference between melt and coolant. The effective distribution coefficient was determined from the resulting crystal purity for each condition. An empirical equation modified from the analytical solution for the mass transfer boundary layer was proposed in this work to relate the effective distribution coefficient to the initial impurity concentration and growth rate.