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Phosphorylated nanocellulose papers for copper adsorption from aqueous solutions
Mautner, A.; Maples, H. A.; Kobkeatthawin, T.; Kokol, V.; Karim, Z.; Li, K. & Bismarck, A.
Abstract
Copper is a major problem in industrial
wastewater streams, seriously affecting the quality of
potential drinking water. Several approaches, including
continuous membrane processes or batch-wise application
of adsorbents, are in use to tackle this problem. Unfortunately, these processes suffer from their particular drawbacks, such as low permeance or disposal of saturated
adsorbents. However, a combination of these processes
could constitute a step towards a more efficient copper
removal solution. Here, we present a nanopaper ion-exchanger prepared from cellulose nanofibrils produced from
fibre sludge, a paper industry waste stream, for the efficient, continuous removal of copper from aqueous solutions. This nanopaper ion-exchanger comprises
phosphorylated cellulose nanofibrils that were processed
into nanopapers by papermaking. The performance of these
phosphorylated nanopaper membranes was determined
with respect to their rejection of copper and permeance. It
was shown that this new type of nanopaper is capable of
rejecting copper ions during a filtration process by
adsorption. Results suggest that functional groups on the
surface of the nanopapers contribute to the adsorption of
copper ions to a greater extent than phosphate groups
within the bulk of the nanopaper. Moreover, we demonstrated that those nanopaper ion-exchangers could be
regenerated and reused and that in the presence of calcium
ions, the adsorption capacity for copper was only slightly
reduced.
Keywords
Cellulose nanofibrils; Heavy metal ion; Ion-exchange; Phosphorylation
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