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In this work, the optimization of synthesis of terpolymer monolith based on glycidyl methacrylate (GMA), ethylene glycol dimethacrylate (EGDMA) and additional cross-linkers: trimethylolpropanetriacrylate (TMPTA) or triethylene glycol dimethacrylate (TEGDMA) was performed. Moreover, novel vinyl functionalized cross-linkable polymers: ethanolamine (EA)/methacryloyl (MAC) modified poly (methyl methacrylate) (PMMA), and hydrolyzed poly (ethylene-co-vinyl acetate) copolymer (EVOH) modified with MAC either directly or via ethyl malonyl chloride/EA bridging group (m-EVA) were used as cross-linkable polymer to improve mechanical/elastic properties of the obtained monoliths. Optimization procedure, performed applying response surface methodology (RSM), was focused on the production of materials with improved dimensional stability/integrity and porosity with abundance of epoxide groups capable for immobilization of lipase from Candida rugosa (CRL). Structural characterization of the synthesized monoliths was determined using FTIR, Raman and H-1 NMR spectroscopies, while morphology/porosity was determined by SEM technique and image analysis; and mechanical properties by diametral compression testing. The most potential monolith containing m-EVA polymeric cross-linker, i.e. GMA/EGDMA/TEGDMA/m-EVA monolith, was used as CRL carrier in a two-step immobilization process. Enzyme loading and the activity of obtained preparations for various initial enzyme concentrations were monitored after 4 and 48 h of immobilization. The resulting catalysts show high potency in biocatalytic reactions with the highest percentage of retained initial lipase activity of 64.5%.

The adsorption performance of three-dimensionally ordered macroporous (3DOM) gamma-alumina was investigated for enhanced Pb2+, Ni2+ and Cd2+ removal. The synthesis was based on a modified sol-gel method using a colloidal crystal template (CCT) method based on PMMA microspheres. The structure was characterized by means of FTIR spectroscopy and XRD analysis. The three-dimensional structure was examined by scanning electron microscopy, which enabled image analysis that showed significantly low shrinkage (8.77%) after calcination at 800 degrees C. The influential parameters, including contact time and adsorbent dosage, were investigated in a batch adsorption study. The adsorption equilibrium and kinetic data were found to be in agreement with the Freundlich isotherm for Pb2+ removal and the Dubinin-Radushkevich isotherm for Ni2+ and Cd2+ removal. The time-dependent adsorption was best described by a pseudo-second-order kinetic model and the Weber-Morris model. High adsorption capacities: 95.39, 23.32 and 25.39 mg/g were obtained for Pb2+, Cd2+ and Ni2+ removal at 45 degrees C, respectively. The existence of interconnected macroporous and mesoporous structures of highly ordered gamma-alumina enabled a higher adsorption capacity in comparison with literature data for others alumina-based adsorbents.