摘要：

On the basis of OCED Guideline 106, batch sorption studies were employed to reveal sorption of atrazine by amending biochar in tropical soils, namely, laterite, paddy soil and dry red soil. Biochar,a micro-porosity and great surface product, was generated by pyrolysis of manioc wastes at 750°C(BC750) and modified substances (MC750) were produced by loading Fe3+. The mechanism of sorption was examined by charactering BC750 and MC750. In this study, carbonization can improve aromaticity, specific surface and alkaline groups of biomass. The isotherms of atrazine in soil seemed closed to linear with partition, whereas the sorption of atrazine in biochar-added soil was a mainly pore-filling mechanism to exhibit nonlinearity. Temkin model was satisfactorily analyzed the sorption isotherm of atrazine by BC750/MC750 into soil with R2 between 0.92~0.998. HI of all the sorbents were greater than 1, which indicated that the desorption rate was higher than the sorption rate. BC750/MC750 had a greater affinity for atrazine in soil than that of unamended soil. And the sorption capacity of unmodified biochar is slightly less than modified biochar, but the desorbed amounts of atrazine are less. Results indicated that biochars derived from agricultural wastes can play a crucial role in the removal of hydrophobic organic chemicals.

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