Nanoporous membranes with cellulose nanocrystals as functional entity in chitosan: Removal of dyes from water

作者：Karim Zoheb; Mathew Aji P^*; Grahn Mattias; Mouzon Johanne; Oksman Kristiina

来源：Carbohydrate Polymers, 2014, 112: 668-676.

DOI：10.1016/j.carbpol.2014.06.048

• Cellulose nanocrystals
• Chitosan
• Nanoenabled membranes
• Dye removal
• Water purification
• Adsorption

Fully biobased composite membranes for water purification were fabricated with cellulose nanocrystals (CNCs) as functional entities in chitosan matrix via freeze-drying process followed by compacting. The chitosan (10 wt%) bound the CNCs in a stable and nanoporous membrane structure with thickness of 250-270 mu m, which was further stabilized by cross-linking with gluteraldehyde vapors. Scanning electron microscopy (SEM) studies revealed well-individualized CNCs embedded in a matrix of chitosan. Brunauer, Emmett and Teller (BET) measurements showed that the membranes were nanoporous with pores in the range of 13-10 nm. In spite of the low water flux (64 Lm(-2) h(-1)), the membranes successfully removed 98%, 84% and 70% respectively of positively charged dyes like Victoria Blue 2B, Methyl Violet 2B and Rhodamine 6G, after a contact time of 24h. The removal of dyes was expected to be driven by the electrostatic attraction between negatively charged CNCs and the positively charged dyes.

• 出版日期2014-11-4