This study investigates the effects of rice husk silica (RHS) as additive in the
polysulfone membrane to enhance antifouling properties in membrane separation
process. The flat sheet PSf/RHS membrane was prepared via phase inversion
technique. The characterization and performance test were conducted on PSf
ultrafiltration membrane prepared from a different additive concentration. The
thermal stability of prepared membrane was observed by using thermogravimetric
analysis (TGA). The cross section area and particles distribution of additive were
carried out by using the scanning electron microscope (SEM) while the surface
morphology was investigated via field emission scanning electron microscope
(FESEM). The surface roughness and hydrophilicity were also determined by using
Atomic force microscopy (AFM) and contact angle measurement respectively.
Meanwhile, the performance was evaluated in term of pure water flux (PWF),
rejection and antifouling properties. The optimized of normalized flux (Jf /Jo) at
different parameter filtration condition (pH, ionic strength and tranmembranepressure)
was
carried
out
by
using
the
response
surface
methodology
(RSM).
From
the
analysis
of
SEM,
FESEM
and
AFM,
results
showed
that
the
microstructure
of
the
membrane
especially at top layer and sub layer obviously changed with the
incorporation of RHS. The results also demonstrated that the mean pore size was
decreased and hyrophilicity was increased as increased RHS particles in PSf
membrane. The performance of the membrane was analyzed by using distilled water
for permeation test and humic acid for the rejection test. The results also showed that
the hydrophilic PSf/RHS membrane has significantly improved the permeation and
rejection performance after the addition of RHS. The results showed that the addition
of 4 wt. % RHS give the highest flux at 300.50 L/m².hour (LMH). The highest
rejection was found at 3 wt. % of RHS membrane with value 98% for UV254 and
96% for TOC. The optimal value of Jf/Jo was found at 0.62 with the parameter
condition pH: 6.10, ionic strength: 0.05 mol/L and transmembrane-pressure: 2.67
bars. Optimize of RSM analysis also proved that the error of model is less than
0.05% which indicates that the model is significant
