单宁酸稳定纳米铁的制备及其迁移性研究OA

The tannic acid-stabilized nano-iron(TA-nZVI)was prepared with the molar ratio of tannic acid to iron of 0.012 5,0.025 0,0.050 0,0.100 0,0.200 0 respectively.The morphology,particle size,composition,stability and dispersion of TA-nZVI were analyzed by TEM,XRD,Zeta and magnetism.Compared with the nano-iron(Bare-nZ-VI)prepared without tannic acid as stabilizer,TA-nZVI was a special cluster structure whose particle size was mainly distributed between 40 and 70 nm.With the increase of tannic acid dosage,the Zeta po-tential value of the corresponding nano-iron particles increased,and the dispersion and oxidation resist-ance of the particles were significantly improved.By studying the sedimentation and migration experiments of TA-nZVI,it was found that with the increase of the amount of tannic acid,the adhesion efficiency of nanomaterials decreased,and the particles were in"non-favorable settling conditions"in the sand col-umn,so that the migration ability of particles was sig-nificantly improved.Among them,the iron nanoparti-cles prepared under the condition of 0.200 0 mole rati-o of tannic acid to iron ion through the dynamic col-umn experiment,the total iron migration rate reached 97.56%,almost no retention phenomenon,17.96 times that of Bare-nZVI under the same condition,which had certain environmental application value.