Abstract：The rice straw was chemically modified to prepare anion adsorbent in order to utilize the excess rice straw in China reasonably and reduce eutrophication at the same time. Characteristics of the anion adsorbent derived from rice straw were analyzed using BET, SEM and FTIR analyzer. Meanwhile, the influence of the adsorbent dosage, initial pH of phosphoric acid solution and temperature to the adsorption capacity were also considered. The results indicated that the modified rice straw was able to absorb phosphate effectively within the pH range of phosphoric acid solution from 4.0 to 10.0 and the optimum adsorbent dosage was 5g/L.The adsorption data fitted the Langmuir adsorption isotherm very much and the maximum adsorption capacity was 1.96 mmol/g.
