功能化壳聚糖改性中空介孔SiO2

以通过溶胶-凝胶法制备的中空介孔SiO₂（HMSiO₂）纳米微球为骨架材料，通过反相微乳液合成使天然高分子壳聚糖（CTS）沉积在HMSiO₂纳米微球表面，随后在铈离子引发下于CTS表面进行丙烯腈接枝共聚并偕胺肟化，制备HMSiO₂复合壳聚糖接枝聚偕胺肟（PAO）复合纳米粒子（HMSiO₂@CTS-g-PAO）。通过FTIR和XRD对HMSiO₂@CTS-g-PAO复合纳米粒子的结构进行表征。采用SEM和激光粒度分析仪对HMSiO₂@CTS-g-PAO复合纳米粒子的形貌和粒径进行探究。结果表明：HMSiO₂@CTS-g-PAO复合纳米粒子的内层为HMSiO₂，外层为CTS-g-PAO，是典型的核-壳纳米粒子。以K₂Cr₂O₇为Cr源，探究HMSiO₂@CTS-g-PAO复合纳米粒子对Cr^Ⅵ的吸附。结果表明，HMSiO₂@CTS-g-PAO复合粒子对Cr^Ⅵ的吸附过程符合伪二级吸附动力学，主要为化学吸附，对pH=2.0、浓度为91.4 mg/L的K₂Cr₂O₇溶液中铬的最大吸附量高达3.28 mmol/g。

Functionalized chitosan modified hollow mesoporous SiO2

A composite nanoparticle hollow mesoporous SiO₂(HMSiO₂)@chitosan-graft-polyamidoxime(CTS-g-PAO) was prepared via HMSiO₂ through sol-gel method used as CTS coating on HMSiO₂ by inverse microemulsion synthesis used as the matrix to graft polyacrylonitrile (PAN), which was transformed to PAO. The component and the structure of the HMSiO₂@CTS-g-PAO composite were examined by FTIR and XRD. The morphology and the size of the HMSiO₂@CTS-g-PAO were confirmed by SEM and Laser Particle Size Analyzer. The results show that the HMSiO₂@CTS-g-PAO is core-shell nanoparticle with the HMSiO₂ as the core and the CTS-g-PAO as the shell. K₂Cr₂O₇ solution is used as the Cr target for detecting the adsorption capacity of the prepared HMSiO₂@CTS-g-PAO. The results indicate that the adsorption capacity of Cr^VI is 3.28 mmol/g when the pH of K₂Cr₂O₇ solution is 2 and the concentration of the solution is 91.4 mg/L. Furthermore, the adsorption process is consistent with the pseudo-second-order kinetics and mainly belongs to chemical adsorption.