Cellulose Acetate Membrane Preparation for Wastewater Treatment

For a long time, humans have used cellulose, as a natural, renewable, and transformative polymer, for scientific development to create new technologies. Cellulose is the most abundant biopolymer on Earth, accounting for more than 50% of terrestrial biomass. For this reason, the treated cellulose (cellulose acetate (CA)) was used in the membrane preparation for water desalination. However, membrane preparation has recently attracted big attention of several research groups. In this case, cellulose acetate (CA), as an inexpensive hydrophilic biopolymer, was chosen as a polymer for preparing the membranes via the inversion phase, since it offers an efficient purification benefit with low energy consumption and less cost. The purpose of this chapter is to describe the various types of membrane preparation based on cellulose acetate, with pathogens, bacteria, and heavy metal (cadmium), and the applications of these membranes in the treatment of contaminated water, to ensure a clean water supply for both human and industrial uses

Dye removal using keggin polyoxometalates assisted ultrafi ltration: characterization and UV visible study

To improve dye retention, there is a concurrent interest in the development and optimization of an alternative and promising method for the dye recovery in aqueous solutions. In this regard, considerable attention was paid to the polyoxometalates (POMs) assisted ultrafiltration (POMAUF). The aim of the present study is to eliminate toluidine blue (TB) dye by ultrafiltration membrane using keggin polyoxometalates (POMs) as complexing agents. In the first step, the keggin polyoxometalates K3[PW12O40]∙6H2O (PW12) and K7 [PW11O39]∙14H2O (PW11) were prepared. Then, the obtained powders were characterized by X-ray diffraction and infrared spectroscopies. Afterwards, the removal of toluidine blue (TB) using polyoxometalates assisted ultrafiltration (POMAUF) was studied. Factors affecting the retention of dye and permeate flux such as transmembrane pressure, operating time, polyoxometalates concentration, ionic strength, surfactant and pH were investigated. All results of both compounds have been presented and discussed. The results reveal that the addition of POMs leads to an increase in dye retention from 11 to 95% for the PW12 and to 98% for the PW11. The results of this work have thus suggested the promising enhancement of ultrafiltration membrane selectivity for the dye removal using new complexing agents such as POMs in place of polyelectrolytes and surfactants