摘要:
本文对中和共沉淀法Fe3O4生成过程中重金属离子并合程度及其影响因素进行了研究,在实验条件下,发现重金属离子在Fe3O4晶格中的并合与其离子半径、电负性和外层电子分布等因素有关。并合程度为:Cu2+,CO2+,Fe2+>Mn2+,Zn2+>Ni2+,Cd2+,当Fe2+/Fe3+=0.5,pH=9.5±0.5时,对40mgCu2+,总铁量(Fe2++Fe3+)2.5g为最小投料量,其并合率可达99.7%以上,相同条件下CO2+并合率大于99.7%,其它重金属离子由于本征特性影响,并合率各不相同,工艺条件适合于污水中Cu2+和Co2+的有效去除,对Mn2+,Zn2+的去除也有一定效果,从沉渣的XRD物相分析可知,重金属离子在Fe3O4中的并合,是以尖晶石型结构取代式固溶体组成完成的。
Abstract:
Heavy metal annexing and related factors in the process of Fe3O4 formation by neutral coprecipitation was studied.It was found that the heavy metal annexing in the crystal lattice of Fe3O4 was influenced by ion radii, electronegativity and the distribution of outlayer electron, and the annexing degree is in the order of Cu2+, Co2+, Fe2+>Mn2+, Zn2+>Ni2+,Cd2+ .The minimum additive amount of total iron (Fe2+ + Fe3+) is 2.5g for 40mg Cu2+ with Fe2+/Fe3+=0.5 and pH9.5�0.5.The annexing ratio can reach 99.7% for Cu2+and 99.7% for Co2+. Annexing ratio of heavy metals are not the same. This process is suitable for effective removal of Cu2+,Co2+ and some other heavy metals in wastewater. By X-ray powder diffraction pattern the annexing of heavy metals in the crystal lattice of Fe3O4 results in the formation of substitutive spinel ferrites solid solution.