Penicillium camemberti lipase immobilized on a magnetized poly(styrene‐co‐divinylbenzene) was used as a biocatalyst for isopropyl palmitate synthesis. The reaction conditions were determined by 22 factorial central composite design. A mathematical model based on a simplified kinetic approach was developed to describe the system and validated with the experimental data. An assay carried out in a stirred‐tank reactor confirmed the proposed model. The ester was purified and the properties such as density and water content were similar to those found in commercially available isopropyl palmitate.

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Dedico este trabalho aos meus pais por sempre confiarem e apoiarem minhas decisões e sonhos AGRADECIMENTOS A Deus, por iluminar meu caminho e ter me concedido forças e capacidade para chegar até aqui. Aos meus pais, Márcia e Giovani, meu irmão e minha cunhada, Guilherme e Walquíria, pelo amor incondicional e incentivo em todos os momentos. À Profª. Drª. Larissa de Freitas, minha orientadora. Obrigado pela orientação, pela oportunidade de desenvolver este projeto, pelos ensinamentos, conversas, atenção, muita paciência e confiança em meu trabalho. Às Profª. Drª. Heizir Ferreira de Castro e Profª. Drª. Patrícia Da Rós e ao Prof. Dr. Leandro Gonçalves de Aguiar, pelas inúmeras contribuições ao trabalho, pela disponibilidade e apoio.

Magnetic polymers supports have proven to be valuable materials for enzyme immobilization, as they allow recovering the catalyst by magnetic separation, precluding the need for costly and time‐consuming separation steps. In this study, magnetic copolymer supports were synthesized using styrene (STY) and different crosslinking agents (divinylbenzene, ethylene glycol dimethacrylate, or triethylene glycol dimethacrylate) and initiators (azobisisobutyronitrile or benzoyl peroxide) and used to immobilize Candida antarctica lipase B (CALB). The aim was to obtain biocatalysts with high enzymatic activity and satisfactory morphological properties for use in biotransformation reactions. Two morphological properties known to influence the immobilization yield were taken into consideration, specific surface area, and swelling index. Experimental data were compared to the predictions of a model based on molar balance, method of moments, numerical fractionation, and elementary gel structures. The high correlation (R2 = 0.9974) between experimental and predicted values demonstrated the suitability of the model for estimating the textural properties of enzyme supports. CALB was successfully immobilized, showing high hydrolytic activity (500–700 U g−1) and good thermal stability at 50°C. CALB/STY‐EGDMA‐M was 14 times more stable than free CALB. The results confirm the efficiency of the immobilization method and the suitability of the copolymers for enzyme immobilization.