Abstract: Through carbonization, pre-oxidization with KMnO₄ and modification with FeSO₄, rice straw was prepared into low-cost modified carbonized rice straw (MCRS). Physical and chemical properties of the carbonized rice straw and MCRS were analyzed with Zeta potential analyzer, scanning electron microscope (SEM), alpha ray spectrometer (ARS), specific surface area analyzer (BET), Fourier transform infrared spectrum analyzer (FTIR) and X-ray diffraction analyzer (XRD). Meanwhile static adsorption tests were carried out to explore effects of dosage of the adsorbent, pH and temperature on phosphate adsorption efficiency of the adsorbent. It was found that phosphate adsorption on MCRS was an endothermic process, and its adsorption isotherm fitted well with the Langmuir equation. In the solution, 7 in pH, 4g•L^-1 of MCRS was added, the phosphate removal rate could reach as high as 96%, and at 30 ℃,it could adsorbed as much as 5.49mg•g ^-1 phosphorus, according to the Langmuir equation.

Key words: rice straw, KMnO₄ preoxidization, modification, adsorption isotherms, phosphate