Laboratory evaluation of operating conditions for chloride removal from diethanolamine using ion exchange resin and introduction of optimal parameters

In this study, a strong anionic resin was used to remove the chloride ion in the diethanolamine of sweetening unit of gas refinery. A laboratory pilot has been investigated as a resin-filled bed to evaluate the reaction temperature, chloride ion concentration, resin saturation, resin recovery rate, optimal reaction temperature, diethanolamine flow rate, hydrogen strength and resin performance in this work. The resin saturation time, capacity of resin, optimal reaction temperature and changes in chloride concentration of the output stream from resin were determined in this research. Finally, the optimal amount of water to regulate the pH of the resin and the optimal amount of 4% sodium hydroxide solution to recycle the resin were calculated. It was found that one liter of resin is able to absorb 20.77 g of chloride. The temperature of 50 degrees C was considered as the optimal temperature of ion exchange reaction by comparing the amount of caustic and water consumption for resin recovery and regulation of neutral acidity, respectively. In this study, the amount of 4 wt.% caustic and water at a temperature of 50 degrees C for recovery of 134 g of resin obtained was equal to 8.5 and 5 L, respectively.

Automated summary

In this study, a strong anionic resin was used to remove chloride ions in the diethanolamine of a gas refinery's sweetening unit. The resin's performance and reaction conditions were evaluated using a laboratory pilot, and optimal amounts of water and sodium hydroxide solution were calculated. The capacity of the resin was found to be 20.77 g of chloride per liter, and a temperature of 50 degrees C was determined to be the optimal reaction temperature.