论文成果

发布时间：

2026-07-13

论文名称：

Preparation of high-performance porous biochar adsorbents from eucalyptus sawdust under supercritical CO2 pretreatment: Mechanistic insights into structure evolution and dye adsorption

发表刊物：

Fuel

摘要：

The efficient conversion of biomass and the controlled fabrication of carbon materials with hierarchical pore structures are of great significance for energy transition and pollution control. However, conventional pyrolysis under inert atmospheres tends to generate tar deposits, which hinder pore development and limit material performance. In this work, biomass was subjected to thermochemical reduction under supercritical CO2 (scCO2) atmosphere, followed by KOH activation to produce activated biochar. The effects of reaction temperature (200–400 ℃) and residence time (20–60 min) on structural evolution and adsorption performance were systematically investigated, with a comparative analysis between scCO2 and N2 atmospheres. The results show that scCO2 regulates carbon structure evolution and alleviates pore blockage by promoting tar migration and cracking, as well as enhancing the carbon-CO2 reaction. The activated biochar exhibited a high specific surface area (759.58–1895.05 m2/g) with a micropore-dominated structure. Compared with N2, scCO2 pretreatment led to a more developed and uniform pore network. The maximum adsorption capacity of the activated biochar, prepared by pre-treatment followed by 20 min reaction at 200 ℃, reached 436.63 mg/g in the methylene blue adsorption experiment. Kinetic analysis indicated that chemisorption plays a dominant role in dye adsorption process (R2 > 0.99). The results demonstrate that adsorption performance is governed by the synergistic effects of pore structure and surface chemical properties. It elucidates the multifunctional role of scCO2 in biomass conversion and pore structure regulation, providing a theoretical basis for the targeted design of high-performance biochar.

卷号：

429

页面范围：

140536

是否译文：

否

发表时间：

2026-07-10