Synthesis of new bacterial cellulose-oriented micropore membrane filter

Abstract

This study investigates a novel synthesis method of bacterial cellulose (BC)-oriented micropore membrane filter and its characteristics. BC-oriented micropore membrane filter has been synthesized by preparation of BC-benzol suspension and evaporation of benzol to render dried BC membrane micro-sized porosity. The structures of BC fibrils before and after hydrolysis are studied by X-ray diffraction (XRD). XRD intensity at 23° (2θ) in HCl-treated BC is higher (73%) than the control (60%), however, the diffraction intensity at 23° (2θ) in BC treated with mixture of H₂SO₄ and HNO₃ is lower(53%) than the control. The SEM analysis reveals that the synthesized BC membrane has many micropores in comparison to the native BC film. The FTIR spectra of cotton cellulose, native BC film and the synthesized BC microfilter showed a band at 3345 and 1643 cm⁻¹ which is assigned to OH stretching vibration and OH deformation vibration and a band attributed to CO asymmetric and symmetric stretching vibration in a range from 1032 to 1166 cm⁻¹, respectively. Maximum pore size, pure water flux, the breakage pressure, ζ-potential and bacteria-retentive efficiency of the filter are characterized. The synthesized microfilter has maximum pore size of 0.2 µm and high water flux of 220 L/m² h under 0.1 MPa. It demonstrates 99.9% filterability against Escherichia coli and Brevundimonas diminuta. The biodegradability test shows that the newly developed BC microfilter is totally decomposed in a month. This suggests that the novel BC microfilter can be a promising candidate for membrane filer used in pharmaceutical, food, cosmetic and water industry.