液化黑藻基炭微球水热制备及吸附诺氟沙星的过程与机制

Preparation of carbon spheres derived from liquefied Hydrilla verticillata by hydrothermal fabrication and their adsorption performance and mechanism for norfloxcin

以沉水植物轮叶黑藻为原材料,采用生物质液化和水热合成技术制备黑藻基炭微球(PCSs),并以磷酸为活化剂对所制备的炭微球进行活化以提升其吸附性能.对PCSs的结构和化学性质进行了表征和分析,同时采用扫描电镜对所制备PCSs的表面形貌进行了观察.并系统研究了PCSs用量、溶液温度及pH值对诺氟沙星(NOR)吸附效果的影响.结果表明,PCSs的BET比表面积、平均孔径、总孔容和等电点分别为67.92 m^2·g^(-1)、6.52 nm、0.11 cm^3·g^(-1)和3.0.PCSs用量、溶液温度及pH值对PCSs吸附去除NOR具有显著的影响,在PCSs用量0.6 g·L^(-1)、溶液温度30℃和pH=6时,10 mg·L^(-1)NOR的吸附去除率可达99.3%.动力学实验表明NOR在PCSs上的吸附行为符合准二级动力学模型,等温吸附曲线符合Langmuir方程,PCSs对NOR的最大单分子层吸附量为36.95 mg·g^(-1).热力学参数表明PCSs对NOR的吸附是一个熵增加的自发吸热反应.

Carbon spheres（PCSs） derived from submerged macrophytes Hydrilla verticillata waste biomass,were prepared by the combination of biomass liquefaction and hydrothermal synthesis,and were activated with phosphoric acid. The structure and chemical properties of the prepared PCSs were analyzed,and the morphology was also observed by scanning electron microscopy. The effects of adsorbent dosage,temperature and pH on the adsorption performance of norfloxcin（NOR） on PCSs were investigated. The results showed that the specific surface area,average pore size,total pore volume and pHzc of PCSs were 67.92 m^2·g^-1,6.52 nm,0.11 cm^3·g^-1and 3. 0,respectively. The adsorbent dosage,temperature and pH had significant effect on the removal efficiency of NOR,and the maximum removal efficiency of 10 mg·L^-1NOR was 99.3% at 0.6 g·L^-1PCSs dosage,30 ℃ and solution pH 6. The adsorption process was governed by pseudo-second-order kinetics. The adsorption fitted the Langmuir equation well,and the maximum adsorption capacity was 36. 95 mg·g^-1. Thethermodynamic parameters revealed that the adsorption process was a spontaneous endothermic reaction with the increase of entropy.