Development of a Novel Experimental Technique for Measuring Equilibrium Adsorption Isotherms Under Dynamic Conditions

A new technique has been developed for measuring equilibrium adsorption isotherms under dynamic conditions. This method involves pressurizing an adsorbent-filled column slowly (under a few sccm) and in such a way that the column is always instantaneously in equilibrium. The system works well for corrosive gasses such as sulfur dioxide, which is commonly found in flue gas and has been known to induce acid rain. In this project, a system was developed and improved to ensure the success of future experimentation. A packed bed of length 21.6 cm and diameter 2.1 cm was used to contain the adsorbent silica gel as well as two layers of glass beads. Experiments were conducted at three temperatures of 30, 50, and 75 ℃. The system was fully regenerated at 200 ℃ for three hours between each run. SO₂ gas was flowed into the system at 5, 10, and 20 sccm to examine whether the resulting column loading plots (i.e., pressure vs column loading) are under isothermal equilibrium. Several plots showing pressure change over time were created and used to develop isotherms and demonstrate the repeatability of the experiments. The mass flow controllers for sulfur dioxide and helium were studied and calibrated for ease of use, and the volume of each system component was calculated. Efficient methods of regeneration for the adsorbent were also examined.