改性活性炭的制备及吸附亚甲基蓝研究

分别采用HNO_3、NaOH、HNO_3与NaOH联用对活性炭进行表面化学改性,考察了投加量、pH值及温度对亚甲基蓝去除率的影响,并对吸附过程进行动力学拟合。结果表明,HNO_3与NaOH联用改性活性炭(YH-C)表面具有较多的碱性基团、酸性基团和内酯基含量,而酚羟基含量很少。活性炭投加量越大,溶液pH值和温度越高,对亚甲基蓝去除效果越好。不同温度和不同pH值下活性炭吸附亚甲基蓝的过程分别符合拟一级动力学方程、二级动力学方程。红外光谱表明,YH-C保留了未改性活性炭的基团,只是峰强度有所不同。

Preparation of Modified Activated Carbon and Adsorption of Methylene Blue

Surface chemical modificated activated carbon were prepared by three kinds of modificated substances such as HNO3, NaOH, both HNO3 and NaOH. The modificated activated carbon was used to adsorb methylene blue and the following factors were considered according to the adsorption process. They were adsorbent dosage, pH value and temperature. And also, kinetics equations were used in the adsorption process. The results showed that, modified by the combined modifier of both HNO3 and NaOH, the activated carbon had more alkaline groups, acidic functional group and lactonic groups, and less phenolic hydroxyl groups. The more dosage of adsorbent and the higher pH value, temperature, the better removal effect of methylene blue. Under different temperature and pH value, the adsorption process of methylene blue matched the pseudo first-order and second-order kinetics. IR spectra showed that YH-C kept the unmodified activated carbon's group, but only the strength of the peak were different.