Abstract: A new phosphorous sorbent was prepared by ferric salt technology in which ferric oxyhydroxide（FeOOH） particles were immobilized on diatomite to produce FeOOH coated diatomite (FCD).Prepared FCD samples were characterized by means of SEM,EDAX,XRD,and physical adsorption etc..From the results of characterization,conclusions were generalized as follows:FeOOH particles were immobilized on the surface of diatomite,causing its micropore and surface roughness changed evidently,and specific surface area became 10 times of unmodified diatomite.In addition,using shaking-bottle-incubating test to simulate natural environment,influences of the factors including FCD dosage,oscillating adsorption time,pH,and temperature on adsorption effect were studied and discussed.According to study results,best adsorption effect was reached at ambient temperature and acidic condition,after oscillating for 3 h.At 25 ℃,pH=3,phosphorous removal rate of 92% was reached,the adsorption capacity was 3.68 mg/g,thus FCD was suitable for phosphorus removal of the Pearl River of which water sample is acidic.Langmuir and Freundlich adsorption isotherm equations can well describe isothermal adsorption characteristics of diatomite to phosphorus,which provide theoretical basis for effectively controlling water eutrophication. 

Key words: eutrophication, modified diatomite, ferric oxyhydroxide, phosphorous removal performance