Immobilization of carobonic anhydrase on functionalized and metal nanoparticles confined mesoporous SBA 15 for CO2 sequestration

Abstract

There is growing concern to indicate that anthropogenic carbon dioxide (CO2) emissions to atmosphere are contributing to global climate change. Many number of CO2 capture and storage technologies have been explored to arrest CO2 during the post-, pre- and oxy-combustion processes. The study involves immobilization of enzyme carbonic anhydrase on functionalized and metal nanoparticles confined mesoporous SBA-15 for CO2 sequestration as CaCO3. Two types of enzymes, Bovine carbonic anhydrase (BCA) and Human carbonic anhydrase (HCA) were immobilized on support materials and used for hydration of CO2 and its sequestration to CaCO3. Mesoporous SBA-15 was synthesized by using tetraethyl orthosilicate (TEOS), pluronic P123 and trimethyl benzene (TMB) as silica source, structure directing agent and swelling agent, respectively. The conventionally synthesized mesoporous SBA-15 were characterized by X-ray diffraction (XRD), N2 adsorption-desorption analysis, Fourier Transform- Infra Red spectroscopy (FT-IR) and Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) analysis. Performance studies, including assays on temperature, storage stability and reusability on the biocatalytic of BCA were studied by p-NPA hydrolysis. Gold nanoparticles confined on APTES/SBA-15, MPTES/SBA-15 and silver nanoparticles confined on TEPA/SBA-15, TAEA/SBA-15 and OAPS/SBA-15 was conventionally synthesized for HCA immobilization. The presence of gold and silver nanoparticles was verified by EDS analysis. Data resulted from different experimental studies at various conditions, it is concluded that the immobilized BCA and HCA retains about 90% of enzymatic activity more than 20 cycles. It is also concluded that the storage stability and thermal stability of immobilized BCA and HCA are better than those of free enzymes. newline newline newline