Influence of nanoparticles on filterability of fruit-juice industry wastewater using submerged membrane bioreactor

Abstract

In this study, polyethersulfone (PES) ultrafiltration membrane surface was modified with nano-sized zinc oxide (nZnO) and silver (nAg) to improve the membrane filterability of the mixed liquor and used to treat fruit-juice industry wastewater in a submerged membrane bioreactor (MBR). The nAg was synthesized using three different methods. In the first method, named as nAg-M1, PES membrane was placed on the membrane module and nAg solution was passed through the membrane for 24 h at 25 ± 1 °C. In the second method, named as nAg-M2, PES membrane was placed in a glass container and it was shaken for 24 h at 150 rpm at 25 ± 1 °C. In the third method, named as nAg-M3, Ag nanoparticles were loaded onto PES membrane in L-ascorbic acid solution (0.1 mol/L) at pH 2 for 24 h at 150 rpm at 25 ± 1 °C. For the preparation of nZnO coated membrane, nZnO nanoparticles solution was passed through the membrane for 24 h at 25 ± 1 °C. Anti-fouling performance of pristine and coated membranes was examined using the submerged MBR. The results showed that nZnO and nAg-M3 membranes showed lower flux decline compared with pristine membrane. Moreover, pristine and coated PES membranes were characterized using a permeation test, contact angle goniometer, and scanning electron microscopy.

A Comprehensive Review on Polymeric Nano-Composite Membranes for Water Treatment

“…In order to mimic polymer membrane fouling, various solutions are available such as traditional methods which involves physical cleaning via backwash (A process where permeate is used in flushing membrane backwards), relaxation (prior to filtration process), chemical cleaning of membrane using acids, caustic soda and hypochlorite, changing flow mode (cross flow filtration and low flux operation) and ultrasonic entrenchment prior to installation are some of the strategies to avoid fouling [49] 3 , Zeolite, Silver to form hybrid materials results in enhancement of membrane hydrophilicity, water flux, improved mechanical, selectivity, permeability, increase in salt rejection, chemical and thermal stability. Due to improvement in hydrophilicity of membrane and being cost effective, fabrication of membrane material using nano-materials is an easy and well-developed method [50][51][52][53][54].…”

Manufacturing and Characterisation of Polymeric Membranes for Water Treatment and Numerical Investigation of Mechanics of Nanocomposite Membranes

“…On the other hand, the most significant disadvantage of PES membranes is that their resistance to clogging is low because of their hydrophobic nature. However, it is possible to increase the resistance against clogging by using PES as the matrix material of nanocomposite membranes [11][12][13][14]. PVDF membranes show hydrophobic properties.…”

Manufacturing, Characterisation and Mechanical Analysis of Polyacrylonitrile Membranes

“…The reinforcements can be in different forms such as particle, platelet/sheet or fibre, and materials like graphene, carbon nanotubes, and clay. These reinforcements affect mechanical properties significantly as well as the treatment performance of the membranes [31,64,65].…”