不同改性活性炭吸附苯酚和亚甲基蓝的实验研究

Experimental Study of Absorption of Phenol and Methylene Blue with Different Modified Activated Carbons

选用木质、果壳、椰壳和煤质4种不同材质的活性炭,经过HNO_3酸化和Na OH碱化,选出对苯酚和亚甲蓝吸附效果最好的活性炭,并进行最佳投加量,最佳pH值和最佳吸附时间的研究。结果表明:碱化木质炭比表面积大、孔隙发达,吸附效果最好。对于初始浓度为1 g/L的苯酚和亚甲基蓝溶液,最佳投加量分别为1.5 g和0.5 g。当pH<10时,碱化木质炭对苯酚有较高的去除率,pH值对亚甲基蓝影响不大,在强酸,中性及碱性溶液中吸附效果更佳。碱化木质炭对苯酚的吸附速度高,在极短时间内去除率高达到88%。当亚甲基蓝的吸附时间在20 min之后,碱化木质炭对亚甲基蓝的吸附趋于平衡,去除率达90%。

In this paper, activated carbons prepared from wood, shell, coconut shell and coal were selected and modified by nitric acid and sodium hydroxide for determination of the one with best removal efficiency of phenol and methylene blue. Simultaneously, study of the optimal dosage, pH value and adsorption time was also conducted. The results showed that the adsorption effect of alkali modified wooden activated carbon was the best with larger specific surface area and developed porosity. The optimal dosages for the phenol and methylene blue solutions with initial concentration of lg/L were 1.5 g and 0.5 g respectively. When the value of pH was below 10, the alkali modified wooden activated carbon had higher removal rate of phenol, but the pH value had little influence on methylene blue removal. The adsorption effects were better in strong acid, neutral and alkaline solutions. The alkali modified wooden activated carbon had high adsorption rate of phenol, with the removal rate reaching to 88% within a rather short time. After 20 minutes, the adsorption of methylene blue by the alkali modified wooden activated carbon tended to balance with the removal rate of 90%.