Abstract:
A rapid increase in population worldwide is giving rise to many issues, safe drinking
water availability being the most important one. There is a need to find ways that are
effective and economical to be able to meet this challenge. For this purpose, membrane
technology has shown a lot of promise but face the biggest challenge of fouling that
reduces its life time. Fouling is the continuous buildup of materials that are deposited
on membrane surfaces clogging the pores resulting ultimately in membrane failure.
Chitosan and activated carbon have been proved to add value to the polymer
membranes. Chitosan not only improves membranes hydrophilicity but also increases
its anti-fouling properties. Activated carbon maintains taste and odor of the water and
also acts as excellent adsorbent that also helps in reduction of fouling. Ultrafiltration
polyethersulfone membranes were synthesized in two different concentrations i.e. 16
% wt. and 20 % wt. Chitosan, activated carbon and thiolated chitosan were
incorporated individually in both the concentrations to see their effect on
polyethersulfone membranes. The membranes were then incorporated with
chitosan/activated carbon and thiolated chitosan/activated carbon to evaluate the
changes in property by introducing modified chitosan having thiol groups. The
membranes were then analyzed using ATR-FTIR, SEM, Optical profilometry,
Mechanical Testing and Contact angle. Gravimetric analysis was done to gauge the
effect on mean pore size. Water uptake and permeability rate was done to investigate
flux rate. BSA (Bovine serum Albumin) was performed to assess the antifouling
activity with change in fillers. The results show a general improvement in the
membranes properties with the addition of chitosan/activated carbon and thiolated
chitosan/activated carbon composites. The results showed increased hydrophilicity,
mean pore size and water retention abilities. SEM micrographs also showed better
channels for permeability with the addition of composites. Surface roughness for
thiolated chitosan/Activated carbon composite was observed at 20 % wt. The
mechanical properties for thiolated chitosan/activated carbon incorporated PES
membranes showed decrease in mechanical properties which may be because of its
solubility in water and high hydrophilicity. There was a significant increase in flux
rate and BSA flux. Apart from membranes incorporated with only chitosan, the best
BSA flux was shown by 20 % wt. thiolated chitosan/activated carbon composite
membrane
