磁场作为一种物理强化零价铁去除四价硒的手段，可以极大地提高零价铁的反应活性。在不同温度下，磁场可以大大提高零价铁去除四价硒的速率。当温度为15℃、不加磁场时，在720 min内可去除90%左右的四价硒，但是加磁场后只需要90 min就可以将去除率提高至99%以上。磁场存在时四价硒的快速去除伴随着二价铁的快速释放。在静置条件下，磁场依然可以提高硒的去除率。当磁场存在时，纤铁矿是其主要的腐蚀产物。磁场对零价铁处理实际的含硒废水亦有很大的提高作用，外加弱磁场时零价铁可以在100 min内将硒的浓度降低至国家污水综合排放二级标准以下。%Magnetic field, a physical means, can greatly improve Se ( IV) removal by zero-valent iron ( ZVI) . In the presence of magnetic field, a higher removal rate of Se ( IV) by ZVI was achieved at different temperatures. When the temperature was 15℃, more than 90% Se ( IV) could be removed within 90 min in the presence of magnetic field, but 720 min in the absence of magnetic field, at the same time magnetic field led to a quicker re-lease of Fe2+. Under static conditions, the removal of Se ( IV) was also enhanced by magnetic field. In the pres-ence of magnetic field, the main corrosion products were lepidocrocite. Magnetic field also had a remarkably im-proved effect on smelting wastewater treatment. Se ( IV) was removed below the national standard of wastewater discharge within 100 min. Thus, applying an external magnetic field is an environmental friendly and energy-free approach to enhancing the Se ( IV) removal by ZVI.
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