Preparation of Amino-Modified SBA-15 Mesoporous Molecular Sieves Co-immobilized Double Enzymes/Epoxy Composite Coating and Its Corrosion Resistance

Amino-modified SBA-15 mesoporous molecular sieves were prepared first. The amino-modified SBA-15 mesoporous molecular sieve was used as a carrier to immobilize lysozyme and lipase respectively, and the immobilization conditions were optimized. The optimal conditions for co-immobilization of double enzymes on amino-modified SBA-15 mesoporous molecular sieve were determined by orthogonal test. The co-immobilized double enzymes were added to epoxy resin to prepare a composite coating. Polarization curve method and electrochemical impedance method were used to analyze the corrosion resistance of the composite coating. The results show that the optimal conditions of co-immobilization of double enzymes were as following: the mass fraction of lysozyme was 0.2 g/L and the time of immobilizing lysozyme was 6 h, the mass fraction of lipase was 0.8 g/L and the time of immobilizing lipase was 10 h. The composite coating added with 1.5% (mass fraction) immobilized double enzymes had the best corrosion resistance, its corrosion inhibition efficiency hit 96.61%.