Application of an Organic Plant-derived Binder in the Fabrication of Diatomaceous Earth Waste- Based Membranes for Water Purification Systems

Abstract

This work reports on the use of diatomaceous earth (DE) waste and organic binder derived from Corchorus olitorius, locally known as “Mrenda” in the design of an efficient water filtration membranes. Charcoal powder was incorporated to enhance the porosity of the membrane. The firing was done at temperatures varying from 700.0 °C to 1150.0 °C. The DE waste samples comprised 79.0% silica (by mass) and 11.0% total flux content compared to porter's clay that had 50.0% silica, 28.8% AL2O3 and 7.0% total flux content. On the other hand, the “Mrenda” binder contained 6.5% total organic matter. The use of the plant- derived binder enhanced the mechanical strength of the greenware by 52.7% and the fired membranes by 152.2%. The fabricated DE waste-based membranes were 15.0% stronger than clay-based ceramic membranes prepared under similar conditions. A sintering temperature of 900.0 °C was optimal in producing porous membranes for filtering of 4.1 liters of water per hour. The pore diameter of the membranes fabricated from DE waste only ranged between 2.0 nm – 99.0 nm. On micro-organisms filtering efficacy, the DE waste-based membranes and those fabricated with 5.0% charcoal were 99.9% and 88.4% effective in the removal of E. coli and Rotavirus respectively.