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In this thesis immobilized laccase for the synthesis of magnetic material and used to degradation of 2,4 - dichlorophenol. The source of the paper used magnetic Fe304 particles and γ-Fe2O3 load mesoporous SiO2. Fe3O4 and γ-Fe203 nanoparticles favored because of its magnetic, catalytic and anisotropic properties widely used in the biomedical, environmental and other fields. Immobilized laccase is recyclable through the strong magnetic field, and its activity can remain active within a longer time. The first portion with the thermal solvents Synthesis Fe304 magnetic particles, the preparation of the magnetic particles are dispersed in ethanol, to prepare a magnetic fluid standby. The using improved StOber method, successfully synthesized a chain of Fe3O4 @ SiO2 composite. Use of APTES on the composite material made of the amino function, and ultimately the amination of the synthetic chain structure nano-magnetic carrier. Laccase by glutaraldehyde immobilized laccase in the amination nano-magnetic carrier, thereby preparing immobilized laccase, and crosslinker concentration, immobilization time, enzyme concentration, temperature, and pH, etc. , it was found that the optimum conditions of the amination nano-magnetic carrier immobilized laccase: 25 ℃, the glutaraldehyde concentration of 5%, and the crosslinking time 8H, contained the enzyme an amount of 40mg / g, a pH of 4.5 , immobilization time 6h. Immobilized laccase degradation of 2,4 - dichlorophenol, 2,4-DCP concentration, reaction pH of the solution, the influence of temperature on the degradation process, found 35 ℃, 2,4 - dichlorophenol concentration 6.5mg / L, pH of the solution was 5.0, 2,4 - dichlorophenol removal rate of 85%, the degradation rate of 43%; dynamics study laccase degradation of 2,4 - dichloro- The activation energy of the phenol found the laccase at room temperature degradation of 2,4 - dichlorophenol. Also studied the fixed enzyme can be reused, and storage stability. It was found that, compared with the free enzyme fixed enzyme degradation of 2,4 - dichlorophenol reusability improved significantly after the continuous degradation of 5 times, the degradation rate remains over 30%. The second part of the first P123 templating agent, TEOS as a silicon source, the synthesis of spherical mesoporous silica spheres (MSS). Impregnated with Fe (NO3) 3-alcohol solution and then calcined in an argon gas atmosphere for MSS microspheres obtained spherical mesoporous magnetic material, i.e. the of MSS coated γ-Fe2O3. Mesoporous magnetic material via its amino group, to give the amino mesoporous magnetic carrier APTES processing. Laccase is fixed on the magnetic carrier of the amino mesoporous prepared immobilized laccase, crosslinker concentration, immobilized time, enzyme concentration, temperature, and pH, etc. in terms of the influence of the immobilized laccase, was found with amino mesoporous magnetic carrier immobilized laccase best conditions are: 25 ℃, the glutaraldehyde concentration of 4%, and the crosslinking time 8H, contained the enzyme an amount of 50 mg / g, a pH of 5.0, and the immobilization time for 6h; obtained immobilized laccase degradation of 2,4 - dichlorophenol, 2,4-DCP concentration, reaction pH of the solution, the influence of temperature on the degradation process, found in 35 ℃, 2,4 - dichlorophenol concentration of 6.5mg / L, solution pH of 5.5, 2,4 - dichlorophenol removal rate of 88%, the degradation rate of 47%. Immobilized enzyme degradation rate remained above 34% after reused five times
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