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This article purified vermiculite and hydroxy-Fe ion solution for different time , preparation of the three low polymerization hydroxyl iron - vermiculite complex . By chemical analysis , electron microprobe analysis , powder X - ray diffraction analysis , differential thermal analysis as it is, by means of vermiculite the low polymerization hydroxy iron - Vermiculite complex characterization . The composite characterization results show that the composite body iron only partially into the vermiculite structural interlayer , and most are deposited on the surface of the vermiculite , the formation of the water content of the iron oxide phase . The content of the vermiculite surface iron phase and increased with increasing duration of action of vermiculite and hydroxy-Fe . In actual soil acidity ( pH = 4 to 7) and temperature (20 to 40 ° C ) conditions, iron ion solution with the vermiculite and a hydroxyl group three months obtained oligomerization hydroxy-Fe - vermiculite composite adsorption harmful elements chromium and arsenic experiments to explore the relationship between the complex arsenic , chromium adsorption capacity and pH, temperature , adsorption time , arsenic and chromium initial mass concentration and ionic strength , and vermiculite arsenic , chromium adsorption the behavior of the contrast. The adsorption results show that , under the experimental conditions , the composite body having a strong chromium and arsenic adsorption capacity, its chromium, arsenic adsorption amount is significantly higher than the vermiculite . Chromium , arsenic initial mass concentration affect the complex chromium , arsenic adsorption amount of the most important factors , pH, followed by . The adsorption time (12 hours later) , the smaller the impact of temperature and ionic strength on the amount of adsorption of composite chromium, arsenic . Acidic soil conditions , the complex has a strong and stable chromium, arsenic adsorption capability . Studies have shown that under the experimental conditions , low polymerization hydroxy-Fe - vermiculite composite body of arsenic, chromium, have a significant affinity , low polymerization hydroxy-Fe - vermiculite composite adsorbed arsenic , chromium process there may be surface rocks and soil important geochemical processes , an important factor is the impact of arsenic , chromium on the surface , especially soil migration, enrichment .
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