Inorganic Rare Earth-based Adsorbent For Fluoride In Drinking Water, Arsenic Adsorption Studies

Arsenic pollution and fluorine pollution in drinking water attract more and more people's attention. Research and develop new effective adsorbent is the focus for the present. This dissertation compiled many data, we find that high effective adsorbent is practical in water purification, and that to develop this adsorbent need high technique. According to character of rare earth's specific physical chemistry, such as specific electron composition, large atom magnetic torque, ligand range from 3 to 12 when combined with other elements, diversity of compound crystal structure, we develop three adsorbent: hydrous Zirconium, hydrous Cerium and CTA. We made expriment on their physical chemistry character, adsorbent property and adsorbent mechanism. The experiment results: 1. impaction of pH is very large on adsorption capacity, in acid water it conducive to adsorption but in alkli it declines capacity and when pH value is higher than 11 the adsorbent can hardly adsorb; 2.we adopt Freundlich Equation and longmiur equation to depict adsorbent's adsorption. 3.high adsorption speed 4.it is simple to desorpt and use proper sodium hydroxide; 5.we compared with alumigel and find that the three adsorbent can adsorb arsenic and fluorine very large and effectively and they can use in wide pH value range. 6.Through column experiment we grope the proper condition and adsorption capacity.By virue of contemporary analytical machine such as infrared analysis, EMS, XRD, and potentiometric titration, we speculated the adsorption mechanism: the adsorbent proper hydroxyl plays an important role in eliminating arsenic and fluorine.To make pratical material we made a further step to mould the powder into granule to imitate on- the -spot experiment. The result showed that rare earth based adsorbent can adsorb well, eradicate effectively and regenerate easily, so they are effective and economical adsorbent.