Effect of Liquid Viscosity on the Liquid Phase Mass Transfer Coefficient of Packing

Abstract

Abstract There are many correlations of liquid phase mass transfer coefficient ( kL ) for packings in the literature; most were developed without data that vary liquid viscosity ( μL ) significantly ( 2 capture by amine scrubbing, μL , of aqueous amine may be significantly greater than water, which makes it important to know how mass transfer is affected by μL . A research plan is proposed to measure the effective mass transfer area ( ae ) and kL in a pilot-scale packed column with μL from 1 to 100 cP. Glycerol was chosen as the viscosity enhancer for its complete solubility in water and the Newtonian behavior of its aqueous solution. Models were built to estimate the physical properties ( μL , ρ , DCO 2 , HCO 2 , γ ) of CO 2 /NaOH/H2O/glycerol based on literature data. Kinetic data ( kg’ ) for the system were obtained with a wetted wall column (WWC). The kinetic data, kg’ , was found to initially increase with glycerol concentration because of the catalytic effect of glycerol, then decrease rapidly because of the increase in μL . The overall reaction rate constant ( kAlk ) was determined from kg’ data, and was found to increase with glycerol concentration until it becomes asymptotic. This model for kg’ will be used for future measurement of ae and kL in a pilot-scale column.