载镧活性氧化铝的除氟及再生性能研究

Fluorine removal and regeneration of lanthanum-loaded activated alumina

为研究载镧活性氧化铝对F-的吸附能力,文中实验利用浸渍法合成载镧活性氧化铝,分别探究吸附时间、pH值、吸附剂用量、干扰离子对吸附过程的影响,同时利用不同浓度的NaOH溶液对吸附剂进行再生,探究吸附剂的再生效果。结果表明:对于质量浓度为10 mg/L的F-溶液,吸附剂用量为5 g/L,其除氟效率为86%,酸性条件下有利于F-的吸附,其最佳除氟pH值为6,各种阴离子对吸附的影响顺序为CO^(2-)_(3)>PO^(3-)_(4)>SO^(2-)_(4)>Cl->NO^(-)_(3),再生实验中,浓度为0.25 mol/L的NaOH溶液对材料再生性能最好,并且经历5次循环再生后其除氟效率保持在70%以上。通过静态吸附实验表明:载镧活性氧化铝具有良好的除氟实际应用潜力,该改性材料为废水除氟工业应用提供依据。

To study the adsorption capacity of the lanthanum-loaded activated alumina on F-,the impregnation method was used to synthesize the lanthanum-loaded activated alumina,the effects of the adsorption time,pH,dosage,interference ions on the adsorption process were explored,at the same time,different molar concentration of NaOH solutions were used to regenerate the adsorbent for the purpose of exploring the regeneration effect.The results show that for F-solution of 10 mg/L,the dosage is 5 g/L,and the fluorine removal efficiency is 86%.It is beneficial to the adsorption of F-under acidic condition,and the best pH for fluorine removal is 6,the order of the effects of various anions on the adsorption is CO^(2-)_(3)>PO^(3-)_(4)>SO^(2-)_(4)>Cl->NO^(-)_(3).The NaOH solution of 0.25 mol/L has the best regeneration performance for material by conducting regeneration experiments,after 5 regeneration cycles,the fluorine removal efficiency remains above 70%.The static adsorption experiment shows that the lanthanum-loaded activated alumina has good practical application potential for fluorine removal,and the modified material provides the basis for industrial application of wastewater fluorine removal.