768
L. Rozhdestvenska et al.
Regarding the PAN-3 sample, similar regularities are observed for the BSA
filtration evidently due to impossibility of protein macromolecules to penetrate
into membranes. However, smaller OVA species remain on the pore walls due to
smaller size. They are adsorbed on the pore walls. It is similar for fouling of the
composite membranes with organic species and inorganic colloidal particles, which
are contained in tap water.
The reason for this is partially hydrophobic surface of the modifier. This is
possible when aggregated GO nanosheets penetrate into the polymer pores during the
membrane modifying. As known, the surface of aggregates is hydrophobic [52, 63].
9 Conclusions
Composite materials based on polyacrylonitrile polymers were synthesized by modifying commercial membranes with HZD–GO composite. The particles of the inorganic ion exchanger are covered with GO nanosheets. The composite forms a
“secondary active layer” inside polymer membranes. Its thickness was estimated
according to the Kozeny–Carman equation, these values are about 3–12% of the
total membrane thickness.
The effect of polymer matrix on ion transport and fouling with organic substances,
particularly with OVA and BSA proteins, has been found. Large pores of polymer
matrix evidently provoke the deposition of GO aggregates inside the membrane. This
provided hydrophobicity of pore walls. As a result, the fouling mechanism involves
adsorption of organic species on pore walls similar to pristine polymer membranes.
Moreover, GO swelling causes acceleration of diffusion of alkaline metal ions. The
modified membrane with smaller pores shows slow diffusion of monovalent ions. The
mechanism of fouling is the cake formation: the precipitate can be easily removed
from the outer surface of the membranes. In all the cases, HZD–GO composite
provides rejection of hardness ions (10–14%) as well as BSA and OVA (95–98%).
References
1. Roy S, Ragunath S (2018) Emerging membrane technologies for water and energy sustainability: future prospects, constrains and challenges. Energies 11:2997. https://doi.org/10.3390/
en11112997
2. Babenyshev SP, Nesterenko PG, Bratsikhin AA et al (2018) Hydrodynamics and mass transfer
with gel formation in a roll type ultrafiltration membrane. Foods Raw Mater 6(2):350–357
3. Macedo A, Monteiro J, Duarte E (2018) A contribution for the valorisation of sheep and goat
cheese whey through nanofiltration. Membranes 8(4):114. https://doi.org/10.3390/membranes
8040114
4. Santibáñez L, Córdova A, Astudillo-Castro C et al (2019) Effect of the lactose hydrolysis on
galacto-oligosaccharides mixtures subjected to nanofiltration: a detailed fractionation analysis.
Sep Purif Technol 222:342–351
L. Rozhdestvenska et al.
Regarding the PAN-3 sample, similar regularities are observed for the BSA
filtration evidently due to impossibility of protein macromolecules to penetrate
into membranes. However, smaller OVA species remain on the pore walls due to
smaller size. They are adsorbed on the pore walls. It is similar for fouling of the
composite membranes with organic species and inorganic colloidal particles, which
are contained in tap water.
The reason for this is partially hydrophobic surface of the modifier. This is
possible when aggregated GO nanosheets penetrate into the polymer pores during the
membrane modifying. As known, the surface of aggregates is hydrophobic [52, 63].
9 Conclusions
Composite materials based on polyacrylonitrile polymers were synthesized by modifying commercial membranes with HZD–GO composite. The particles of the inorganic ion exchanger are covered with GO nanosheets. The composite forms a
“secondary active layer” inside polymer membranes. Its thickness was estimated
according to the Kozeny–Carman equation, these values are about 3–12% of the
total membrane thickness.
The effect of polymer matrix on ion transport and fouling with organic substances,
particularly with OVA and BSA proteins, has been found. Large pores of polymer
matrix evidently provoke the deposition of GO aggregates inside the membrane. This
provided hydrophobicity of pore walls. As a result, the fouling mechanism involves
adsorption of organic species on pore walls similar to pristine polymer membranes.
Moreover, GO swelling causes acceleration of diffusion of alkaline metal ions. The
modified membrane with smaller pores shows slow diffusion of monovalent ions. The
mechanism of fouling is the cake formation: the precipitate can be easily removed
from the outer surface of the membranes. In all the cases, HZD–GO composite
provides rejection of hardness ions (10–14%) as well as BSA and OVA (95–98%).
References
1. Roy S, Ragunath S (2018) Emerging membrane technologies for water and energy sustainability: future prospects, constrains and challenges. Energies 11:2997. https://doi.org/10.3390/
en11112997
2. Babenyshev SP, Nesterenko PG, Bratsikhin AA et al (2018) Hydrodynamics and mass transfer
with gel formation in a roll type ultrafiltration membrane. Foods Raw Mater 6(2):350–357
3. Macedo A, Monteiro J, Duarte E (2018) A contribution for the valorisation of sheep and goat
cheese whey through nanofiltration. Membranes 8(4):114. https://doi.org/10.3390/membranes
8040114
4. Santibáñez L, Córdova A, Astudillo-Castro C et al (2019) Effect of the lactose hydrolysis on
galacto-oligosaccharides mixtures subjected to nanofiltration: a detailed fractionation analysis.
Sep Purif Technol 222:342–351