纳米羟基磷灰石绿色合成及其对Cd^(2+)的吸附

Green synthesis of nano-hydroxyapatite and its adsorption performance for Cd^(2+)

以黑曲霉发酵液为基质实现了温和条件下纳米吸附剂羟基磷灰石(bHAP)的绿色合成。利用SEM-EDS、XRD、FTIR、TG-DTA等手段对bHAP进行表征分析,并考察其对水中Cd^(2+)的吸附行为和机理。实验结果表明:黑曲霉发酵液辅助合成的bHAP呈圆形片状结构,分散性良好,颗粒尺寸小于200 nm,且含丰富的生物官能团。静态吸附实验证实,在pH=7、初始质量浓度为50 mg/L的Cd^(2+)溶液中投加0.5 g/L的bHAP,吸附8 h后bHAP对Cd^(2+)的饱和吸附容量达93.81 mg/g。吸附过程符合准二级动力学模型和Tempkin吸附等温模型。机理分析表明,黑曲霉辅助合成的bHAP对Cd^(2+)的吸附去除是离子交换和表面络合共同作用的结果。

Nano-adsorbent hydroxyapatite(bHAP)was greenly synthesized with Aspergillus Niger fermentation broth under mild conditions.The bHAP sample was characterized by SEM-EDS,XRD,FTIR and TG-DTA,and its adsorption performance and mechanism were examined.The results show that bHAP is disc-shaped with abundant biological functional groups.The sample disperses well with the average particle size less than 200 nm.The static adsorption experiment shows that the maximum adsorption capacity of bHAP on Cd^(2+)is 93.81 mg/g under the conditions of pH=7,reaction time 8 h,and the initial Cd^(2+)mass concentration 50 mg/L by adding 0.5 g/L bHAP to Cd^(2+)solution.The adsorption process conforms to the pseudo-second-order kinetic model and the Tempkin adsorption isothermal model.The mechanism analysis proves that the adsorption process of Cd^(2+)by bHAP is controlled by ion exchange and surface complexation.