樟树叶生物炭对挥发性有机物的吸附研究

Research on the adsorption of volatile organic compounds by camphor leaves biochar

以樟树叶为原料制成的生物炭作为吸附剂,对挥发性有机污染物(Volatile organic compounds,VOCs)的吸附特性进行研究。结果表明:生物炭对不同物质的饱和吸附量与其分子粒径和沸点成负相关。甲苯、四氯甲烷、1,2-二氯乙烷和1,2,4-三甲基苯4种物质在生物炭中的饱和吸附量分别为228.4,275.2,253.4,176.6 mg/g。生物炭吸附甲苯的穿透时间为2.97 min,达到穿透点后,吸附效率会显著下降。不同组分同时吸附存在抑制作用,导致单个组分饱和吸附量降低,但吸附总量有所增加,表明不同组分之间也存在一定的叠加效应。同时,利用热再生法能够有效地再生生物炭,再生利用率达到91.3%。因此,樟树叶生物炭可以作为一种有效的、可再生的VOCs吸附剂。

The adsorption characteristics against VOCs were studied using biochar made from camphor leaves.The results showed that the saturated adsorption of this biochar against different substances was affected by molecular weight and boiling point of these substances in a negatively correlated manner.The capacities of toluene,tetrachloromethane,1,2-dichloroethane and 1,2,4-trimethylbenzene were 228.4,275.2,253.4 and 176.6 mg/g,respectively.The breakthrough time of toluene adsorption by biochar was 2.97 min.After reaching the breakthrough point,the adsorption efficiency will decrease significantly.Simultaneous adsorption of multiple components will lead to competitive adsorption,resulting in the decrease of saturated adsorption concentration of single component.However,the total adsorption amount increased,which indicated that there could be certain synergistic effect among different components.Meanwhile,the thermal regeneration method can effectively regenerate biochar,and the regeneration utilization rate reached 91.3%.Therefore,camphor leaf biochar can be used as an effective and reproducible VOCs adsorbent.