关键词: 羟基氧化铁, 超疏水膜, 膜接触器, 膜吸收, 二氧化碳

Abstract:

To achieve carbon peaking and neutrality targets, the development of efficient carbon capture technologies is essential. Membrane absorption, which integrates chemical absorption with emerging membrane technology, holds advantages of both methods. However, its absorption performance is restricted by membrane wetting. In this study, a superhydrophobic PVDF membrane was prepared via in-situ FeOOH growth and low surface energy substance grafting. The successful modification of superhydrophobic FeOOH/PVDF membrane was confirmed through scanning electron microscope, Fourier infrared spectrometer, X-ray photoelectron spectroscopy, contact angle analyzer, etc. The static water contact angle of the modified membrane was 152.6° and the rolling angle was 8.2°, proving it's superhydrophobic. CO₂ membrane absorption experiments revealed that the modified membrane held CO₂ removal rate that higher than 50% under various operating conditions, showing good absorption performance. In a 40-hours membrane absorption experiment, the modified membrane consistently maintained an average absorption flux of 4.4mmol/(m²∙s), while the pristine membrane got wet within 20hours and its flux decreased to 2.8mmol/(m²∙s), proving the significant role of superhydrophobic modification in enhancing the membrane's lifespan.

Key words: iron hydroxide oxide, superhydrophobic membrane, membrane contactor, membrane absorption, carbon dioxide