(442f) Dissolution of Activated Sludge Biomass in Imidazolium-Based Ionic Liquids

Activated sludge biomass (ASB), the solid produced during biological treatment of wastewater contains a network of polysaccharides and proteins collectively known as extracellular polymeric substance (EPS).  The nature of ASB predicts that it may behave similarly with cellulose upon dissolution in ionic liquids (IL). Cellulose dissolution in ionic liquids is well-known and studied. In this work, ASB was dissolved in various ionic liquids such as 1-butyl-3-methylimidazolium chloride ([BMIM][Cl]) and 1-allyl-3-methylimidazolium chloride ([AMIM][Cl]), both of which are recognized to dissolve cellulose effectively. The biomass was recovered after precipitation with water. The regenerated ASB was characterized by Thermogravimetric Analysis (TGA). The bulk structure was observed through Scanning Electron Microscopy (SEM). Factors such as the nature of the ionic liquid, ASB homogeneity and temperature effects (microwave irradiation versus direct heating) on dissolution were investigated. Establishing successful dissolution parameters of ASB in imidazolium-based IL’s will open doors for new ASB utilization i.e. sugar source for biofuels production.