Fabrication of low cost, green silica based ceramic hollow fibre membrane prepared from waste rice husk for water filtration application

In order to develop low cost ceramic membranes and effectively utilize abundantly and dumped waste agriculture, fabrication of green silica based ceramic hollow fibre membranes from waste rice husk was evaluated. Rice husk was converted into amorphous and crystalline silica based rice husk ash (ARHA and CRHA) by burning process at 600 °C and 1000 °C, respectively. The properties of silica based rice husk ashes were studied by transmission electron microscopy (TEM), x-ray powder diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), BET analysis, thermogravimetry and differential thermal analysis (TG/DTA) and x-ray fluorescence (XRF). Effect of silica content and sintering temperature towards membrane fabrication were investigated and characterized in term of morphological properties, mechanical strength, surface roughness, pore size distribution, porosity and pure water flux (PWF). The ceramic hollow fibre membrane (CHFM) prepared at 37.5 wt% CRHA content and sintered at 1200 °C achieved a good mechanical strength (71.2 MPa) and excellent porosity (50.2%). As a result, high PWF with value ~ 300 L/m2 h and stable at 20 min was obtained. Due to the excellent pure water flux, the prepared ceramic membrane from waste rice husk hold promise for water treatment application.