摘要
咖啡渣为咖啡副产品，因其产量丰富、组分多样而使研究学者对其资源化利用产生广泛关注。文章以咖啡渣为原料，采用水热法制备咖啡渣基水热炭，并分析碱处理方式对水热炭材料形貌、表面官能团及U（VI）吸附性能的影响。实验结果显示，由浓度为3 mol/L氢氧化钾溶液处理后的咖啡渣制备出的水热炭（AHOC）表面更为疏松多孔，含氧官能团更多，且U（VI）吸附性能最佳；温度对三种水热炭U（VI）吸附性能的影响并不一致，碱溶液处理咖啡渣基水热炭（HAC）对U（VI）的吸附量随温度升高而升高，咖啡渣基水热炭（HOC）和AHOC在298 K时的U（VI）吸附量高于288 K和308 K；咖啡渣基水热炭具备较快的U（VI）去除速率，在反应60 min时可达到平衡；咖啡渣基水热炭去除U（Ⅵ）的过程中除吸附作用外还存在还原作用。
关键词： 咖啡渣；水热炭；碱处理；铀；吸附
Abstract
Coffee grounds, a byproduct of coffee production, have garnered significant attention from researchers due to their abundant availability and diverse composition, prompting exploration into their potential resource utilization. In this study, coffee grounds were utilized as raw materials to synthesize hydrochar, with an analysis conducted on the impact of alkaline treatment on the morphology, surface functional groups, and U(VI) adsorption capabilities of the resulting material. The results revealed that coffee grounds treated with a 3 mol/L KOH solution yielded hydrochar (AHOC) with a more porous surface, increased oxygen-containing functional groups, and exhibited superior U(VI) adsorption performance. The influence of temperature on the U(VI) adsorption performance of the three hydrochar materials was found to be inconsistent. The adsorption amount of U(VI) by HAC increased with increasing temperature, while the adsorption amount of U(VI) by HOC and AHOC at 298 K was higher than that at 288 K and 308 K. Furthermore, the coffee grounds based hydrochar demonstrated rapid U(VI) adsorption kinetics, reaching equilibrium within 60 minutes of reaction. Importantly, the coffee grounds based hydrochar not only exhibited adsorption behavior towards U(VI), but also demonstrated reduction effect.
Key words： Coffee grounds; Hydrochar; Alkali treatment; Uranium; Adsorption
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