Diatomite has a huge specific surface area, and the particles contain a large amount of silicon hydroxyl. The silicon hydroxyl will dissociate H + in aqueous solution, so that the surface of diatomite has a strong negative charge. It is an adsorbent with excellent performance.
In order to further improve the adsorption performance of diatomite, a large number of researchers have carried out a series of modification work. The modified diatomite can be used to treat domestic sewage, wastewater containing heavy metal ions, papermaking wastewater and printing and dyeing wastewater.
Fan Yi et al. Synthesized zirconium modified diatomite by surface crosslinking method. It was found that the phosphorus adsorption capacity of zirconium modified diatomite was higher than that of pure zirconia adsorbent. For eutrophic lake water with phosphorus concentration of 2mg / L, when the dosage of zirconium modified diatomite was greater than 1.25g/l, the phosphorus concentration in the water body after reaction could meet the class III standard of lake and reservoir specified in the environmental quality standard for surface water. Wang Fang modified diatomite with transition metals (Fe, Cu, Zn). When the addition of Fe is 7%, the adsorption capacity of ammonia nitrogen is 1.18mg/g, and the removal rate of ammonia nitrogen is 2.19 times that of unmodified diatomite.
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