Removal of ammonium salt from aqueous solution of glycolic acid with macroporous resin

Effects of main properties of eight resins on the removal of (NH4)2SO4 from the aqueous solution of glycolic acid (GA) were studied via the dynamic adsorption separation method in the fixed-bed column. The results indicated that the breakthrough capacity (Q) and the saturation capacity (Qe) for eight resins gradually decreased with enhancing temperature and flow rate, and the breakthrough volume and the saturation volume had a similar variation trend. Moreover, higher polarity of resin or larger specific surface area of resin could enhance separation capability, and smaller pore size of resin was advantageous to the removal of (NH4)2SO4. The change degrees of Q and Qe of GA for different polarities of resins were greater than that of Q and Qe of (NH4)2SO4 under different temperatures, whereas Q and Qe of smaller specific surface area of resin and larger pore size of resin showed a contrary trend. In addition, HPD950 resin with larger specific surface area and lower polarity and suitable pore size was suitable choice for removal of (NH4)2SO4 from the aqueous solution of GA.