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Hanyang Univ. Preparation of Nanoporous Silica and its Application for Enzyme Immobilization. Jong-Kil Kim,Jin Koo Park and Ho-Kun Kim Dept. of Applied Chemistry HanYang University. Inorganic Advanced Material Lab. Trend of Bio-chem. Process in 21st Century. Chem-Syn Bio-Synthesis
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Hanyang Univ. Preparation of NanoporousSilica and its Application for Enzyme Immobilization Jong-Kil Kim,Jin Koo Park and Ho-Kun Kim Dept. of Applied Chemistry HanYang University Inorganic Advanced Material Lab.
Trend of Bio-chem. Process in 21st Century • Chem-SynBio-Synthesis • (VOC useWaterBase) • PollutionPro->Envirn-Friendly • Limit Condition RX->RoomTemp • H-Cost,L-Effi->L-cost H-Effi Worldwide Trend of Medicine,Food, Fine Chemical Industry Strategy Bio-Conversion process - biocatalyst -Immobilization tech Hanyang Univ. Inorganic Advanced Material Lab
Bioconversion processes using immobilized enzymes Immobilization yield vs. pore diameter. Covalent Immobilization of D-amino acid oxidase to Nano-porous silica. 3APTES (3-aminopropyltriethoxysilane)
Hanyang Univ. Bioconversion processes using immobilized enzymes
Hanyang Univ. Classification of Silica • Natural/Synthetic • Crystalline/Amorphous • Porous/Nonporous • Hydrophilic/Hydrophobic • Pure/ Composits
Hanyang Univ. Typical precipitated silica Silica MFG by Wet process Liquid reaction Silica gel & precipitated silica Na2O·xSiO2 + 2HCl +nH2O 2NaCl + xSiO2 nH2O + H2O Due to liquid reaction, water can not be removed totally from product. Water content is about 4-6% in the products.
Gel type silica • Na2O·xSiO2 + 2HCl +nH2O 2NaCl + xSiO2 nH2O + H2O Acid excess Surface Area : 250-850m2 /gr Pore Size : 2.5 - 30nm
White Carbon (precipitated silica) • Na2O·xSiO2 + 2HCl +nH2O 2NaCl + xSiO2 nH2O + H2O Base excess Surface Area : 150-250m2 /gr Pore Size : 15 - 25nm
Hanyang Univ. What is Nanoporous Gel ? • A nanoporous solid • Produced by sol-gel procedure • high surface area • small pore size. • High porosity • low density
Hanyang Univ. What is the structure of Nanoporous Gel ? • A three-dimensional • Highly branched network • Primary particles(2-20nm) • Aggregate into larger(㎛-mm)particles. • Pore dimensions of 3-100nm
Hanyang Univ. Application of Nanoporous material • Separation Materials • Filtering device • Catalysts support • Cell immobilization • Battery materials • Advanced biomaterials • Thermal Insulators
Hanyang Univ. Preparation of nano porous silica Sodium Silicate Hydrochloric acid Reaction hydrosol Silica content temp Gelation Raw gel Time, Temp. Wet treatment hydrogel Time, temp, flow rate,pH Drying Temp, Time Drying&size control Pressure, Temp Feed rate Final product Xerogel,Aerogel
BET Specific SurfaceArea 700-1000m2/g 600m2/g 500m2/g 400m2/g 300m2/g 200m2/g 100m2/g 50m2/g Primary Silica Particle Size 3-4nm 5nm 6nm 7.5nm 10nm 15nm 30nm 60nm pH 7-10, Na2SO4<Iso Electric Point Primary Silica Particles Grow pH<7 or pH 7-10, Na2SO4>Iso Electric Point Gelation and Three-Dimensional Gel Network Gel Type Silica Area Precipitated Type Silica Area Aging Process