纳米Al2O3-海藻酸钠联合固定化小球藻去除水中总磷

Removal of Total Phosphorus by Nanometer Al2O3 and Sodium Alginate Jointly Immobilized Chlorella vulgaris

针对以海藻酸钠为代表的传统固定化材料制备的微藻胶球传质性能较差,对水中总磷去除率低的问题,开发了纳米Al2O3-海藻酸钠联合固定化小球藻胶球,研究了初始总磷浓度、胶球粒径和粒数对联合固定化小球藻去除总磷的影响。结果表明:纳米Al2O3增加了固定化小球藻胶球的比表面积,促进了小球藻对水中总磷的去除,总磷去除率随着胶球加入量的增加和胶球粒径的减小而提高。纳米Al2O3-海藻酸钠联合固定化小球藻胶球的最优制备方案如下:将0.15 g纳米Al2O3加入到30 m L浓度为1.8%海藻酸钠溶液中,然后再加入小球藻至藻细胞密度为2×106cell/m L,交联CaCl2浓度为1%。胶球重复使用3次时总磷去除率仍达到77.51%。

The microalgae immobilized bead prepared by traditional immobilized materials has the problem of poor mass transfer performance and low removal efficiency of total phosphorus in water.Nanometer Al2O3 and sodium alginate jointly immobilized Chlorella vulgaris was prepared,and the effects of initial total phosphorus concentration,bead size and number on removal of total phosphorus in water were explored.The nanometer Al2O3 increased the specific surface area of the immobilized Chlorella vulgaris bead and promoted its removal efficiency of total phosphorus,and the removal efficiency of total phosphorus increased with the increase of the dosage of jointly immobilized Chlorella vulgaris and the decrease of particle size.The optimum conditions for beads preparation were as follows:0.15 g nanometer Al2O3 was added to 30 mL sodium alginate solution with a concentration of 1.8%,then Chlorella vulgaris was added with algae cell density of 2×106 cell/mL,and cross-linking agent(CaCl2)concentration was 1%.The removal efficiency of total phosphorus could still reach 77.51%after the jointly immobilized Chlorella vulgaris beads being reused for three times.