CO2 controlled flocculation of microalgae using pH responsive cellulose nanocrystals

Cellulose nanocrystals were grafted with imidazole functionalities up to DS 0.06 using a one-pot functionalization strategy. The resulting nanocrystals were shown to have a pH responsive surface charge which was found to be positive below pH 6 and negative above pH 7. These imidazolyl cellulose nanocrystals were tested for flocculation of Chlorella vulgaris using CO2 to induce flocculation. Up to 90% flocculation efficiency was achieved with 200 mg L(-1) dose. Furthermore, the modified cellulose nanocrystals showed good compatibility with the microalgae during cultivation, giving potential for the production of reversible flocculation systems.crosscheck: This document is CrossCheck deposited related_data: Supplementary Information identifier: Wim Thielemans (ResearcherID) copyright_licence: The Royal Society of Chemistry has an exclusive publication licence for this journal copyright_licence: This article is freely available. This article is licensed under a Creative Commons Attribution Non Commercial 3.0 Unported Licence (CC BY-NC 3.0) history: Received 11 June 2015; Accepted 25 July 2015; Accepted Manuscript published 28 July 2015; Advance Article published 7 August 2015; Version of Record published 20 August 2015status: publishe