Kinetics and removal formula of methyl mercaptan by ethanol absorption without neglecting solute accumulation.

The wet scrubbing process is commonly adopted for organic odor treatment. In this study, methyl mercaptan (CHSH) was selected as a representative hydrophobic organic odorant which was treated using an ethanol solution in a scrubbing tower. Results showed that the ethanol solution can retain the ideal CHSH removal effect for 2.0 h. The following experimental conditions were set: intake load of 4,700 m mh, spraying load of 5,100 L mh, and volume ratio of ethanol/water at 1:5. The solute accumulation of CHSH in the scrubbing liquid exceeded 3.01 × 10 kmol CHSH/kmol ethanol when the scrubbing tower operated for more than 2.0 h. The mathematical formula which neglected solute accumulation in the ethanol solution exhibited poor adaptability to the removal effect of CHSH by ethanol absorption. The CHSH removal effect of solute accumulation in the ethanol solution was explored in long-term operation. Meanwhile, the CHSH removal rate formula which considered solute accumulation in the ethanol solution could be calculated as η = a'-b'X/Y. The kinetic parameters of the formula fitting results were phase equilibrium constant m 0.0076, and overall mass transfer coefficient K 4.98 kmol mh in the scrubbing tower. These findings can serve as a reference for engineering design and operation for the removal of CHSH by ethanol absorption.