Investigation the fouling behavior of HDPE-silica nanocomposite membrane in the filtration of humic acid solution
Paper ID : 1144-MST2015-FULL
Ali Akbari, Reza Yegani *, farhad mansourizadeh
Sahand University of Technology
Polyethylene as a membrane material possesses many desirable properties including excellent mechanical strength, thermal and physicochemical stability and low cost compared with other commercial polymers. However, PE membranes exhibit a low water flux compared to other membranes prepared from hydrophilic polymers because of their hydrophobic nature and absence of polar functional groups in PE molecular chains. Furthermore, its water flux continuously decreases during the filtration process in aqueous solutions specially water treatment process due to fouling, originating from hydrophobic interactions between the membrane and the feed solution. The foulants in drinking water include suspended inorganic particles, bacteria, algae, viruses, and naturally organic matter (such as humic acid) all of which may, potentially, adsorb to the membrane surface and pores resulting in pore blocking and accumulation on the membrane surface. Therefore, hydrophilic modification of the PE membranes to change the anti-fouling property of these membranes has attracted great attention. In the present work, silica nanoparticles were used to improve the hydrophilicity and antifouling characteristic of PE membrane. The properties of HDPE mixed matrix membrane were investigated using FE-SEM and pure water flux. Furthermore, the fouling characteristics of the membranes were examined for the separation of humic acid (HA) solution as one of the main foulants in water treatment process. Finally, the fouling mechanism of membranes was analyzed using hermia models to investigate the effect of nanoparticles on the fouling mechanisms of polyethylene membrane. Results showed that pure HDPE membrane had low flux about 11 L/m2h. However, water flux increases in the presence of nanoparticles about 2.73-fold higher than that of pure HDPE membrane. It was observed the model that best describe the experimental data for pure HDPE and silica NPs/HDPE membranes is the cake formation mechanism.
HDPE, Silica nanoparticle, Membrane Fouling, Humic acid filtration
Status : Conditional Accept (Oral Presentation)