淀粉纳米颗粒的高效制备及吸附性能

Highly efficient preparation of starch nanoparticles and their adsorption capacity

以木薯淀粉为原料,在微波和超声波双外场的作用下采用沉淀法制备淀粉纳米颗粒(starch nanoparticles,SNPs)。通过动态光散射仪(dynamic light scattering,DLS)、场发射扫描电镜(scanning electronic microscope,SEM)、原子力显微镜(atomic force microscope,AFM)、比表面积分析仪(Brunner-Emmet-Teller,BET)对SNPs进行表征,考察了SNPs对番红花红T的吸附机理,进一步考察了时间、吸附剂的投加量、粒径对吸附的影响。结果表明:SNPs具有较好的球形形貌,是V型淀粉晶体结构,Zeta电位值为-23. 7 m V,比表面积大大增加。在番红花红T的质量浓度为200 mg/L,吸附时间为60 min,温度为298. 15 K的条件下,投加20 mg平均粒径为40 nm的SNPs,吸附量可达115 mg/g。SNPs对番红花红T的吸附过程符合准二级动力学模型和Langmuir等温吸附模型。

Cassava starch was used as raw material to prepare starch nanoparticles (SNPs) in a microwave-ultrasonic reactor via precipitation. The structure and morphology of SNPs were characterized by dynamic light scattering (DLS), scanning electronic microscope (SEM), atomic force microscope (AFM), and Brunner-Emmet-Teller (BET). The adsorption capacity of SNPs to adsorb saffron red T, as well as effects of time, adsorbent dosage, and particle size were investigated. The results showed that SNPs were spherical and exhibited a V-type crystallinity. Their ζ-potential value was -23.7 mV, and their specific surface area greatly increased. It was found that 20 mg SNPs with an average size of 40 nm could adsorb 115 mg/g saffron red T when there were 200 mg/L saffron red T adsorbed for 60 min at 298.15 K. The process of SNPs adsorbing saffron red T conformed well to a pseudo-second-order kinetic model and a Langmuir isothermal adsorption model. In conclusion, this study provides an experimental basis for applying SNPs in treating environmental water.