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采用氧化沉淀法在羧甲基纤维素(CMC)体系中制备了以纳米Fe3O4为核心,外包覆羧甲基纤维素的复合纳米Fe3O4.对比研究了复合纳米Fe3O4和微米Fe3O4对水中磷的吸附以及对土壤中磷的固化,并考察了添加纤维素酶在此过程中所起的作用.结果表明,在水中微米Fe3O4的平衡吸附量为3.2 mg/g,而复合纳米Fe3O4为2.1 mg/g.当将纤维素酶(用以降解包覆在氧化铁表面的羧甲基纤维素)添加到复合纳米Fe3O4吸附磷的溶液中,复合纳米Fe3O4的除磷效率(86%)接近于微米Fe3O4(90%),说明羧甲基纤维素的存在减弱了复合纳米Fe3O4的吸附能力.在土柱实验中,将2种Fe3O4悬浊液注入到10 cm高的土壤柱中,72%的复合纳米Fe3O4穿过土壤柱溢出,而微米Fe3O4完全滞留在土壤柱中没有溢出.原始土壤的固磷率为30%,注入复合纳米Fe3O4的土壤固磷率达到45%,而将纤维素酶和复合纳米Fe3O4一起注入土壤中固磷效率提高到74%.
The composite nano-Fe3O4 coated with carboxymethylcellulose with nano-Fe3O4 as the core was prepared by carboxymethylated cellulose (CMC) system by oxidative precipitation method. The effects of composite nano-Fe3O4 and micro-sized Fe3O4 on phosphorus adsorption in water And the effect of adding cellulase in the process of immobilizing phosphorus in soil.The results showed that the equilibrium adsorption capacity of Fe3O4 in water was 3.2 mg / g, while that of composite Fe3O4 was 2.1 mg / g When cellulase (used to degrade the carboxymethyl cellulose coated on the surface of iron oxide) was added into the solution of composite nano-Fe3O4 for adsorbing phosphorus, the efficiency of removing phosphorus (86%) of composite nano-Fe3O4 was close to that of micro-Fe3O4 90%), indicating that the presence of carboxymethyl cellulose weakened the composite nano-Fe3O4 adsorption capacity.In the soil column experiment, the two kinds of Fe3O4 suspension into 10 cm high soil column, 72% of the composite nano-Fe3O4 Spilled through the soil column, while the micro-Fe3O4 completely retained in the soil column does not overflow.The solid content of the original soil was 30%, the composite solid Fe3O4 composite soil solid-P rate reached 45%, and the cellulase and composite nano-Fe3O4 Pour into the soil with phosphorus efficiency increased to 74%.