Preparation Of Porous Carrier Immobilized Enzyme And Its Performance For Efficient Degradation Of Organic Pollutants

The number of contaminants released into water bodies is growing along with the global population and industrialisation,which is leading to major global water pollution issues.However,secondary contamination is a common issue with traditional physicochemical approaches of pollutant treatment.Because of its low cost and capacity to reduce pollutant concentration,bioremediation has received a lot of attention lately.Enzyme remediation is preferred over whole biological organisms because it is less susceptible to environmental influences and maintains a higher catalytic effect at lower pollution concentrations.However,there are drawbacks to using free enzymes,including low stability,sensitivity to temperature and p H fluctuations,and undesirable transport and preservation.Therefore,it was suggested to immobilize the enzyme on the substance to increase its stability,lengthen its duration of preservation,and reduce cost.In this paper,to create magnetic mesoporous silica（Fe₃O₄@d-SiO₂@p-SiO₂）microspheres with a core-shell structure,Fe₃O₄ microspheres were first produced as precursors by the hydrothermal method,covered with a thin coating of dense SiO₂（d-SiO₂）,and then with a layer of mesoporous SiO₂（p-SiO₂）.The ideal circumstances and mechanism of the immobilized enzyme were examined.Porous Fe₃O₄@d-SiO₂@p-SiO₂ was utilized as a carrier to immobilize laccase through adsorption.The findings demonstrated that the immobilized laccase had a wider p H and temperature range than the free laccase,high activity was retained at p H 4-10 and temperature 20℃-40℃respectively and that the immobilized,enzyme activity was still retained at 58%after 10 cycles and at 80%after 20 days of storage.Finally,the immobilized enzyme was used to degrade the benzo[a]pyrene,and it was discovered that at p H=5,30°C,and a starting concentration of 10 mg/L,the immobilized enzyme had the maximum degradation efficiency,the removal rate reached 99%.The manufacture of immobilized enzyme carriers and their use in environmental treatment are discussed in this work along with some research questions to consider.