Smart and Reusable Biopolymer Nanocomposite for Simultaneous Microalgal Biomass Harvesting and Disruption: Integrated Downstream Processing for a Sustainable Biorefinery

One of the major technological challenges in developing a microalgal biorefinery is to minimize the fossil energy inputs, particularly in two important downstream unit operations, cell harvesting and disruption. Hence, this study involved synthesizing and applying biopolymer nanocomposite to achieve concomitant biomass harvesting, cell disruption, and nanocomposite recovery by exploiting its cationic, photocatalytic, and magnetic properties respectively, in an integrated and optimized process chain. Accordingly, dual-functionalized chitosan-TiO2 conjugated particles (CTC) and trifunctionalized magnetic nanocomposites (MNCs) namely, chitosan coated core–shell structures of Fe3O4–TiO2, were prepared and characterized. The harvesting efficiency of >98% was achieved at the optimal dosages of chitosan, CTC and MNCs of 0.11, 0.09, and 0.07 g g–1 Chlorella minutissima biomass, respectively. TiO2 driven photocatalysis could effectively disrupt harvested wet-biomass, when exposed to UV irradiation in the presence ...