羟丙基壳聚糖纳米微粒的制备及其对Ni^(2+)的吸附研究

Preparation of hydroxypropyl-chitosan nanoparticles and their properties for Ni^(2+) absorption

通过在碱性条件下将羟丙基引入到壳聚糖分子上,再利用离子凝胶法制备羟丙基壳聚糖(HCS)纳米微粒。结果表明,HCS溶液的质量浓度为0.8～2.0mg/mL、多聚磷酸钠(TPP)的质量浓度为0.4～1.5mg/mL时,均可以生成HCS纳米微粒。粒径分布表明,HCS纳米微粒主要粒径约为200～300nm,粒径分布较窄。HCS纳米微粒对工业电镀废水中的Ni2+吸附性能研究表明,粒径小的HCS纳米微粒对Ni2+的吸附容量要大于粒径大的吸附容量;HCS取代度越高,则对Ni2+吸附容量就越大,吸附能力越强。脱附实验表明,4种脱附剂的脱附能力总体为H2SO4>HCl>HNO3>EDTA,前3种酸的脱附能力相当,都较EDTA脱附能力强,重现性较好,且使用H2SO4时,脱附时间只需30min便能达到87%以上的脱附率。

Hydroxypropyl was introduced into chitosan under the alkaline condition,the hydroxypropyl-chitosan（HCS） nanoparticles was prepared through the ion-gel technologies.Results showed when HCS concentration was 0.8-2.0 mg/mL and sodium tripolyphosphate（TPP） concentration was 0.4-1.5 mg/mL,HCS nanoparticle could be generated.The nanoparticle size was mainly ranged from 200 nm to 300 nm,the size distribution was narrow.Applying the obtained HCS nanoparticles to removal the Ni2＋ from industrial electroplating wastewater,results showed the smaller nanoparticles had a better adsorption capacity for Ni2＋.The higher substitution degrees of HCS,the greater adsorption capacity of HCS nanoparticles to Ni2＋.The desorption experiment demostrated that the performance of 4 desorption agents follow the order of H2SO4HClHNO3EDTA.Appling H2SO4 as desorption reagent and desorption for 30 min,the desorption rate could achieve over 87%.