利用X射线粉末衍射(XRD)、透射电子显微镜(TEM)、差热重量分析法(TG)、比表面积分析仪(BET)等研究了除铁除锰水厂富含铁锰氧化物的反冲洗泥经过不同焙烧温度处理后的产物结构变化对吸附除砷的影响.结果表明:铁锰氧化物反冲洗泥原料为无定型结构,粒径小且比表面积大,能高效除砷;焙烧温度为150℃时,结晶水开始脱除,比表面积与孔容变化不大,As(III)和As(V)的去除率均略微增加;焙烧温度为500℃时,脱羟基反应促使微孔逐渐合并成介孔,比表面积降低,As(III)和As(V)的去除率降至70％;当焙烧温度升高到800℃后,热处理产物脱水完全,微孔和介孔随焙烧温度升高逐渐合并成大孔,比表面积和孔容分别下降至12.755m2/g和0.052cm3/g,平均孔径增长了约10nm,且产生的赤铁矿晶体颗粒间出现烧结现象,对As(III)和As(V)的去除率大幅下降,为原来的10％左右.%Structural change of iron and manganese oxide sludge which were calcined in air at different temperatures, was analyzed by X-ray powder diffraction, transmission electron microcopy, differential thermogravimetry and nitrogen adsorption analysis for specific surface area, respectively. And also the adsorption behaviors towards As was investigated. The results show that the iron and manganese oxide sludge is amorphous structure, with high efficiency of arsenical removal, due to its characteristics of small particle size and big specific surface area. Crystallization water beganto lose at 150℃, and specific surface area and pore volume had a little change,with As (III) and As (V) removal rate increased slightly corresponding.Dehydroxylation reaction at 500℃made the micropores gradually merge into mesopores , leading to the decrease of specific surface area, and further dramatically decrease of As (III) and As (V) removal rate by 30％ of the original value. As the temperature rising to 800℃, the micropores and mesopores gradually merged into macropores, resulting in the increase of the average pore diameter by 10nm, and the reduce of the specific surface area and pore volume to 12.755m2/g and 0.052cm3/g, meanwhile the sintering phenomenon generated between hematite crystal particles ,which made the removal rate of As (III) and As (V) plunge to about 10％ of the original value.
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