四氧化三铁-蛭石复合材料制备及其对Pb^(2+)的吸附性能

Synthesis of Fe_3O_4-vermiculite composite and its adsorption performance for Pb^(2+)

以天然蛭石为载体制备了四氧化三铁-蛭石复合材料,采用静态平衡实验对该复合材料吸附Pb^(2+)的特性进行了研究,同时考虑了pH值、温度和投加量对吸附的影响.结果表明,四氧化三铁-蛭石复合材料对Pb^(2+)的吸附等温线符合Langmuir方程和Freundlich方程,Elovich方程和双常数方程可较好地描述该复合材料对Pb^(2+)的吸附动力学过程.由Langmuir等温式计算得出,在30℃、pH 5.50、投加量1.50 g·L^(-1)时,四氧化三铁-蛭石复合材料对Pb^(2+)的最大吸附量为128 mg·g^(-1).四氧化三铁-蛭石复合材料对Pb^(2+)的吸附量均随pH值、温度和投加量的增大而增加.与天然蛭石的对比实验表明,四氧化三铁-蛭石复合材料表现出较高的磁饱和强度且Pb^(2+)吸附能力提高55.5%.

In this study,Fe3O4-vermiculite composite was synthesized using natural vermiculite as carrier,and its adsorption performance for Pb2＋ in aqueous solution was studied by batch experiments under conditions of different pH values,temperatures and adsorbent dosages. The results showed that the adsorption isotherms of Pb2＋ in aqueous solution was well described by both Langmuir and Freundlich equations,and the adsorption kinetic fitted well with Elovich equation and double constant equation. The adsorption capacity of Pb2＋ in aqueous solution increased with the increase of pH value,temperature and adsorbent dosage,respectively. The maximum adsorption capacity of Pb2＋ in aqueous solution was 128 mg·g-1 under the condition of pH 5.50, 30 ℃, and 1.50 g·L-1 adsorbent dosage. Compared with natural vermiculite,the Fe3O4-vermiculite composite showed higher saturated magnetic intensity and its adsorption capacity was increased by 55.5%.