Department of Environmental Science, Faculty of Natural Resources, University of Guilan, Rasht, Guilan, Iran.
Department of Environmental Science, Faculty of Natural Resources, Tarbiat Modares University, P.O. Box 46414-356, Noor, Iran.
Environ Sci Pollut Res Int. 2019 Sep;26(26):26542-26552. doi: 10.1007/s11356-019-05842-3. Epub 2019 Jul 10.
The economic potential of activated carbon (AC) synthesis from walnut shell biomass for CO capture was evaluated in the present study. For this purpose, the chemical activation was employed to manufacture ACs and the effect of different impregnation ratios of activation agents, comprising KOH (KH) and HPO (HP), onto the properties of fabricated ACs was examined. The obtained results demonstrated that the synthesized AC by HP activation with an impregnation ratio of 1:2.5, which was identified as HP2.5, possesses the highest surface area (1512.6 m/g), micropore volume percentage (74.65%), and CO adsorption (3.55 mmol/g) at 1 bar and 30 °C. Moreover, the equilibrium CO adsorption data for HP2.5 were better fitted with the Freundlich model, indicating the multilayer CO adsorption onto the heterogeneous AC surface dominantly through a physisorption process. In addition, the economic estimations revealed a cost of about $1.83/kg for the ultimate production that was significantly lower than the most of available CACs in the market. Therefore, walnut shells can be considered as a cost-effective and promising biomass source from a scale-up point of view.
本研究评估了从核桃壳生物质合成活性炭（AC）用于 CO 捕集的经济潜力。为此，采用化学活化法制造 AC，并考察了不同活化剂浸渍比（包括 KOH（KH）和 HPO（HP））对所制备 AC 性能的影响。结果表明，用 HP 活化剂以 1:2.5 的浸渍比合成的 AC（HP2.5）具有最高的比表面积（1512.6 m/g）、微孔体积百分比（74.65%）和在 1 巴和 30°C 下的 CO 吸附量（3.55 mmol/g）。此外，HP2.5 的平衡 CO 吸附数据更符合 Freundlich 模型，表明 CO 通过物理吸附过程主要以多层形式吸附到非均相 AC 表面上。此外，经济估算显示，最终生产的成本约为 1.83 美元/公斤，明显低于市场上大多数可用的 CAC。因此，从扩大规模的角度来看，核桃壳可以被认为是一种具有成本效益和前景的生物质资源。
