铁铝复合氧化物/壳聚糖颗粒的制备及其对磷酸盐吸附性能的研究

Preparation of iron-aluminum composite oxides/chitosan particles and study on their adsorption performance to phosphates

采用铁铝复合氧化物对壳聚糖进行改性,制备了铁铝复合氧化物/壳聚糖颗粒(FACP),并用于富营养化水体中磷酸盐的去除。结果表明,采用初始磷质量浓度为30 mg/L的溶液、体积为300 m L、吸附剂投加质量浓度为10 g/L,于(25±1)℃、150 r/min振荡96 h,铁铝复合氧化物/壳聚糖颗粒对磷酸盐的吸附量(2.033 mg/g)远高于壳聚糖(CTS,0.168 mg/g),高于铁铝复合氧化物(Fe-Al,1.533 mg/g)。溶液初始pH为3时,FACP对磷酸盐的最大吸附量为0.99 mg/g。溶液中加入Na Cl对FACP吸附磷酸盐影响不大,表明FACP对磷酸盐具有选择吸附性。通过动力学模型拟合发现,FACP吸附过程由液膜扩散和内扩散共同控制。通过Langmuir模型模拟得出FACP对磷酸盐最大的吸附容量为11.05 mg/g。

Fe-Al composite oxides/chitosan particles(FACP)are prepared through modifying chitosan by Fe-Al composite oxides and used to remove phosphates from eutrophic water.The results indicate that the adsorption capacity of FACP to phosphates reaches 2.033 mg·g^(-1),much higher than either the 0.168 mg·g^(-1)of chitosan or the 1.533 mg·g^(-1)of Fe-Al composite oxides when the initial concentration of phosphates solution is 30 mg·L^(-1),the volume of solution is 300 m L,the adsorbent dosage is 10 g·L^(-1),the temperature is at 25±1℃,the oscillation lasts for 96 h at a speed of 150r·L^(-1).When the solution has an initial p H value of 3,the maximum adsorption capacity of FACP to phosphates is 0.99mg·g^(-1).The addition of Na Cl in the solution has little impact on the adsorption of phosphates by FACP,indicating that FACP has selective adsorption on phosphates.It is found by kinetic model fitting that the adsorption process of FACP is jointly controlled by liquid film diffusion and internal diffusion.It is shown through Langmuir model simulation that the maximum adsorption capacity of FACP to phosphates is 11.05 mg·g^(-1).