生物炭-铁锰氧化物复合材料制备及去除水体砷(Ⅲ)的性能研究

Preparation of Biochar-Ferro Manganese Oxide Composite Material and Properties of Removal of Arsenic(Ⅲ)from Aqueous Solution

采用浸渍法制备了4种不同的生物炭-铁锰氧化物复合材料(F_1M_1BC_(10),F_1M_3BC_(20),F_1M_4BC_(25),F_3M_1BC_(20)),采用SEM,XPS和FTIR表征方法分析了几种复合材料与生物炭表面性质的差异,比较了4种不同配比生物炭-铁锰氧化物复合材料对砷(Ⅲ)去除性能,分析了不同投加量的吸附材料对砷(Ⅲ)去除效率及吸附量的差异。结果表明,与生物炭相比,炭、铁和锰不同配比的生物炭-铁锰氧化物复合材料比表面积明显增大,由61.0 m^2·g^(-1)增加到208 m^2·g^(-1),孔径变小,由23.7 nm下降到2.76 nm;碱性官能团含量明显增加;材料表面形成了MnOx、FeOx。与生物炭相比,4种生物炭-铁锰氧化物复合材料对砷(Ⅲ)的动力学吸附量大小与去除率顺序依次为F_1M_4BC_(25)>F_1M_3BC_(20)>F_1M_1BC_(10)>F_3M_1BC_(20)>BC。F_1M_4BC_(25)(m铁∶m锰∶m炭=1∶4∶25)是去除砷(Ⅲ)最优的复合材料,在用量为0.016 g·m L^(-1)时,对砷(Ⅲ)的去除率可达82.6%,是生物炭去除率的2.3倍。研究表明,生物炭-铁锰氧化物复合材料是一种潜在的去除水体砷污染的炭基材料。

By impregnation method for four kinds of different proportions of biochar-ferro manganese oxide composite（FMBC ） material （F1M1BC10, F1M3BC20, FIM4BC25, F3MIBC20） were prepared. FMBC materials at four different ratios were characterized using SEM, XPS, and FTIR and the As（ Ⅲ） removal efficiencies and adsorbing capacities were studied. When comparing the FMBC with biochar（BC ）, the specific surface area increased from 61.0 m^2·g^-1 to 208 m^2·g^-1, the pore diameter decreased from 23.7 nm to 2.76 nm, and the concentration of basic functional groups increased. MnOx and FeOx were created on surface of FMBC. The As（Ⅲ） removal efficiency and adsorbing capacity using different ratios of FMBC increased significantly compared with BC. The As （Ⅲ ） removal efficiencies and adsorbing capacities were in the order of F1M4BC25〉 FLM3BC20〉FIM1BC10〉 F3MIBC20〉BC, and the As（ Ⅲ ） removal rate of FiM4BC^（Fe：Mn：biochar=1：4：25, mass ratio） （82.6%） was higher than that of BC （35.4%） when their dosage was 0.016 g-mL^-1. This study demonstrated that FMBCs would be potential carbon sorbents for removing As（ Ⅲ ） from polluted waterbodies.