Loading on clay mineral can improve the agglomeration behavior of zero-valent iron particles and enhance their reactivity. Particle agglomeration and reactivity are related to the mass ratio of iron to clay. In this study, CTMAB/A-nZVI-3 and CTMAB/A-nZVI-5 were prepared using organic attapulgite (CTMAB/A) as carrier by liquid phase reduction method when the mass ratio of iron to clay were set to 1:3 and 1:5, respectively. The loaded sample and the unloaded nZVI sample were characterized by X-ray diffractometry (XRD) and scanning electron microscopy (SEM). The product of the sample after reaction with Cr(VI) was analyzed by X-ray photoelectron spectroscopy (XPS). The results showed that with the ratio of iron to clay decreasing, the agglomeration of nZVI particles were improved and the particle size distributions of nZVI were changed. The nZVI particles with particle size less than 10nm accounted for 3.60% in CTMAB/A-nZVI-3, 7.60% in CTMAB/A-nZVI-5, and zero in unloaded nZVI samples. When the amount of iron in supported samples was 0.75g/L, the Cr(VI) removal rateresulting from iron was 86.20% in CTMAB/A-nZVI-5samples and 78.00% in CTMAB/A-nZVI-3samples.
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