摘要
制备了2种负载铁锰氧化物的改性活性炭(FM-GAC-1、FM-GAC-2)并研究其对水中的亚砷酸盐的去除性能.考察了2种改性活性炭除三价砷的吸附等温线、反应动力学及pH、温度、水中共存离子对其去除三价砷的影响,发现FM-GAC-1和FM-GAC-2对三价砷均有较好的去除效果,吸附容量分别为32.37、26.67 mg.g-1.吸附速率符合拟二级反应动力学,化学反应控制过程是改性活性炭除砷的限速步骤.pH值偏酸性有利于吸附的进行,温度升高,吸附容量有所下降,该吸附过程是自发的放热过程.同时,水体中的共存阴离子在其浓度值为三价砷的200倍时,SiO32-、PO32-、NO3-对FM-GAC-1吸附三价砷有明显影响;SiO32-、CO32-对FM-GAC-2吸附三价砷有显著影响.总体上讲,FM-GAC-1较FM-GAC-2有更为优异的去除三价砷性能.
Two kinds of Fe-Mn oxide impregnated GAC（ FM-GAC-1, FM-GAC-2）were prepared and their arsenite removal performance were studied. The adsorption isotherm and reaction kinetic models of arsenite on the two kinds of modified GAC and influence of solution pH, temperature and co-exist anions were investigated in the study. The results showed FM-GAC-1 and FM-GAC-2 can adsorb arsenite effectively, the adsorption capacities were 32.37 mg· g- 1 and 26.67 mg· g- 1 respectively. The adsorb velocity could be predicted well by applying pseudo- second order rate equation and the chemistry reaction process was the limitation of the reaction for both modified GAC. The lower solution pH was benefit to the removal of arsenite. The adsorption capacity of FM-GAC-1 and FM-GAC-2 decreased with temperature increasing. The adsorption processes were spontaneous heat-discharge processes. Some co-exist anions can influence arsenite adsorption on modified GAC when their concentration were 200 times of arsenite. It was found that SiO3^2- , PO3^2- , NO3- had a significant negative influence on arsenite removal by FM-GAC-1 and SiO3^2- , CO3^- can markedly decrease arsenite adsorption on FM-GAC-2. As a whole, FM-GAC-1 had better arsenite removal performance than FM-GAC-2.
出处
《环境科学》
EI
CAS
CSCD
北大核心
2009年第3期780-786,共7页
Environmental Science
