Experimental study on the corrosion behavior and regeneration performance of KCOOH aqueous solution

摘要

The potassium formate (KCOOH) solution is regarded as a promising alternative for the widely used salt solution in liquid desiccant dehumidification. However, few studies have been conducted to investigate the regeneration characteristics of KCOOH solution. In the present study, it firstly measured the vapor pressure of KCOOH solution with different temperature and concentration. Then the corrosion behavior of stainless steel 316L in both KCOOH and LiCl solution was studied with electrochemical test. Finally, experiments were carried out to study and compare the regeneration performance of the two liquid desiccants. Results showed that the vapor pressure of KCOOH solution with the concentration of 64.3% to 73.3% was similar to that of LiCl solution with the concentration of 33% to 38% when the temperature was from 45 degrees C to 65 degrees C. Both the regeneration rate and mass transfer coefficient were almost the same for KCOOH solution and LiCl solution in the same experimental conditions. However, the application of KCOOH solution could reduce the investment of liquid desiccant by up to 931 USD/100 kg, and dramatically alleviate the corrosion as well. In addition, a correlation to predict the mass transfer coefficient was developed and validated with the mean absolute relative deviation of only 3.92%.