Experimental Study on Purification of Acetone Waste Gas by a Novel Composite Absorbent
Acetone, a widely used solvent in the pharmaceutical industry, poses environmental and economic challenges due to its high volatility and the low concentration of acetone in water-based absorbents, which complicates recovery. This study proposes a composite absorbent comprising 1,4-butanediol (BDO), triethylene glycol, sodium citrate, and water, aiming to enhance acetone absorption capacity and enable cost-effective resource recovery. Response surface methodology optimized the absorbent composition to BDO 35%, triethylene glycol 10%, and sodium citrate 5%, achieving an acetone absorption capacity of 51.97 g·kg−1, which is 2.39 times that of pure water (21.77 g·kg−1). Density functional theory (DFT) calculations and AIM topological analysis revealed that BDO forms stronger hydrogen bonds with acetone, characterized by shorter bond lengths and higher electron density, underpinning its superior molecular recognition and absorption capability. Process simulation of absorption-regeneration cycles demonstrated that, compared to pure water, the composite absorbent reduces absorbent consumption by 36.2% and regeneration energy consumption by 41.15% while achieving effluent acetone concentrations below 100 mg·m−3. This multi-scale investigation, spanning macroscopic experiments, molecular mechanisms, and process simulation, validates the feasibility and advantages of BDO-based composite absorbents for VOC control, providing theoretical and data support for the engineering application of alcohol-based absorbents in efficient organic pollutant separation.