August 1st 2022In this study, the measured spectra of acetic anhydride, acetic acid, salicylic acid, and aspirin are used for in situ monitoring of the progression of aspirin synthesis in a reaction system. Traditional methods such as HPLC and titration ultraviolet (UV) absorption are not optimal for such real-time monitoring because of long analytical times and complicated procedures. ATR-FT-IR offers an alternative solution that overcomes the shortcomings of traditional techniques.