纳米Fe/Ni双金属的制备及其对水中2,4-二氯酚的还原效果

 采用液相还原法制备了纳米Fe/Ni双金属材料，分析了FeCl₂浓度、n（Ni）/n（Fe）和n（NaBH₄）/n（FeCl₂）物质的量之比对制得的Fe/Ni双金属还原水中2，4-二氯酚（2，4-DCP）效果的影响，明确了Fe/Ni对2，4-DCP的还原脱氯途径。结果表明：在FeCl₂浓度为3 mol/L、n（Ni）/n（Fe）=4%，n（NaBH₄）/n（FeCl₂）=1的条件下制备的Fe/Ni双金属对2，4-DCP的去除率接近100%，且其中95%被还原成苯酚。纳米Fe/Ni为球形颗粒，粒径约为50 nm，在自身磁力作用下相互链接为枝状，又通过静电稳定作用分散聚集，形成海绵状多孔结构，BET比表面积为44.8 m²/g。纳米Fe/Ni还原2，4-DCP的途径主要是苯环上的2个C-Cl键依次被加氢还原，先脱去一个氯生成2-氯酚或4-氯酚，再进一步脱氯转化为稳态的苯酚。

Study on the preparation of nanoscale Fe/Ni bimetal and its reduction of 2,4-dichlorophenol from aqueous solution

Nanoscale Fe/Ni bimetal is prepared by the liquid phase reduction method. The effects of the FeCl₂ concentration, n(Ni)/n(Fe), and n(NaBH₄)/n(FeCl₂) on the reduction of 2, 4-dichlorophenol(2, 4-DCP) are investigated and the reduction pathway of 2, 4-DCP is confirmed. The results show that when the concentration of the FeCl₂ solution is 3 mol/L, n(Ni)/n(Fe)=4%, and n(NaBH₄)/n(FeCl₂)=1, the removal efficiency of 2, 4-DCP is nearly 100%, with 95% of 2, 4-DCP being reduced to phenol. The morphology of the nano Fe/Ni is spherical particles with diameter of about 50 nm. The Fe/Ni particles are linked into branches by their inherent magnetic force and are aggregated dispersedly owing tothe electrostatic stabilization. The BET surface area of the Fe/Ni particles reaches 44.8 m²/g. The pathway of 2, 4-DCP is mainly attributed to the fact that two C-Cl bands are broken in turns to form 2-chlorophenol or 4-chlorophenol, and then dechlorinated to phenol.