Experimental data were obtained to evaluate the effects of amine additives for pH control of solution and the volumetric flow rate of feed solution on the performance of mixed-bed ion exchange for the removal of ionic impurities in solution. The experiments were performed under various temperatures and cation resin ratios by using a continuous column system with NaCl solution. The breakthrough curves of ions, plotted as the ratio of the effluent to influent concentration versus run time or treated solution volume, give detailed results about the effects of the existence of the pH controller, such as ammonia and morpholine, and the variable flow rate on the fate of each ion in the units. The experimental results show that the morpholine breakthrough occurs earlier than the ammonia breakthrough and that the effect of ammonia on both sodium and chloride exchange rates is more significant than that of morpholine. The addition of ammonia in solution results in the decrease of cation resin capacity for the sodium removal much more than the addition of morpholine. The step changes in the flow rate affect significantly the shapes of sodium and chloride breakthrough curves. The effluent concentrations of sodium and chloride change according to the flow rate. However, the effect increases with decreasing operation capacity of cation resin, while it becomes serious around the breakthrough
time of chloride and negligible after the time.
Bulusu R, Development of a Column Model to Predict Multicomponent Mixed-Bed Ion Exchange Breakthrough, M.S. Thesis, Oklahoma State Univ., Stillwater, Oklahoma, 1994
Carberry JJ, AIChE J., 6, 460, 1960
Cobble JW, Turner PJ, Additives for pH Control in PWR Secondary Water, EPRI NP-4209, Project 1571-3, August, 1985
Harries RR, The Role of pH in Ion Exchange Kinetics, in Ion Exchange for Industry, Ellis Horweed Limited, Chichester, England, 1988
Noh BI, Effect of Step Changes in Feed Concentration and Incomplete Mixing of Anion and Cation Resin on the Performance of Mixed-Bed Ion Exchange, Ph.D. Thesis, Oklahoma State University, Stillwater, Oklahoma, 1992
Pondugula SK, Mixed-Bed Ion Exchange Modeling for Divalent Ions in a Ternary System, M.S. Thesis, Oklahoma State University, Stillwater, Oklahoma, 1992
Yoon TK, Noh BI, Moon BH, The Effect of the Cation to Anion Resin Ratio on Mixed-Bed Ion Exchange Performance at Ultra-low Concentrations, the Third Korea-Japan Symp. on Sep. Tech., Seoul, Korea, 1994
Zecchini EJ, Solutions to Selected Problems in Multicomponent Mixed-Bed Ion Exchange Modeling, Ph.D. Dissertation, Oklahoma State Univ., Stillwater, Oklahoma, 1990