Highly effective photocatalytic decomplexation of Cu-EDTA by MIL-53(Fe): Highlight the important roles of Fe
Highly effective photocatalytic decomplexation of Cu-EDTA by MIL-53(Fe): Highlight the important roles of Fe
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DOI：
10.1016/j.cej.2021.130515
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发表时间：
2021
影响因子：
15.1
通讯作者：
Si-yun He;Tengfei Li;Lan-tao Zhang;Xiaofang Zhang;Ziwen Liu;Ying Zhang;Jingzhen Wang;Hanzhong Ji
中科院分区：
文献类型：
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作者：
Si-yun He;Tengfei Li;Lan-tao Zhang;Xiaofang Zhang;Ziwen Liu;Ying Zhang;Jingzhen Wang;Hanzhong Ji
重金属-有机络合物难以通过经典沉淀法去除。本研究成功制备了MIL-53（Fe）光催化剂，并考察了其对重金属-有机络合物的光催化解络活性。选择乙二胺四乙酸铜（Cu-EDTA）为目标物。实验结果表明，在紫外光照射下，约91%的Cu-EDTA在60 min内被分解，64%在120 min内被矿化。MIL-53（Fe）催化Cu-EDTA脱络合反应主要是由H2+、HO·和1 O2的产生所驱动。MIL-53（Fe）释放的Fe（III）被光生电子和Cu（I）还原为Fe（Ⅱ），抑制了光生电子与h+的复合。更重要的是，Fenton类反应和共沉淀来自释放的Fe（III）促进了Cu-EDTA的解络合。结果，生成了一些小分子化合物，包括甘氨酸、乙酸、次氮基三乙酸、草酸、草氨酸和NO3-。提出了MIL-53（Fe）络合剂对Cu-EDTA的可能解络合途径。考察了共存无机离子和有机物对Cu-EDTA解络合的影响。此外，还探讨了该催化剂对其他重金属络合物的光催化降解潜力。
Heavy metal–organic complexes are difficult to remove by classic precipitation methods. In this study, MIL-53(Fe) photocatalyst was successfully synthesized and its photocatalytic activity for the decomplexation of heavy metal–organic complex was explored. Ethylenediaminetetraacetic acid complexed copper (Cu-EDTA) was chosen as the target. Experimental results showed that approximately 91% of Cu-EDTA was decomposed within 60 min under ultraviolet irradiation (UV), and 64% was mineralized within 120 min. Cu-EDTA decomplexation was mainly driven by the production of h+, HO•and1O2from the MIL-53(Fe). Fe(III) released from the MIL-53(Fe) was reduced by the photogenerated electrons and Cu(I) to form Fe(Ⅱ), which inhibited the recombination of photogenerated electrons and h+. More importantly, Fenton-like reactions and coprecipitation derived from the released Fe(III) promoted the decomplexation of Cu-EDTA. As a result, some small molecular compounds, including glycine, acetic acid, nitrilotriacetic acid, oxalic acid, oxamic acid, and NO3–, were generated. The possible decomplexation pathways of Cu-EDTA by MIL-53(Fe) photocatalysis were proposed. Effects of coexisting inorganic ions and organic matter on Cu-EDTA decomplexation were evaluated. Furthermore, the photocatalytic degradation potentials for other heavy metal complexes were also explored.