Page 469 - Demo

SECTION II. APPLIED BIOTECHNOLOGY IN THE PHARMACEUTICAL INDUSTRY... 473the treatment of ammonium-rich agricultural wastewater%u201d was conducted to investigate and develop new granular biomass based on the mixture of PVA, SA and using GO as a reinforcing agent for effective treatment of ammonium-rich wastewater. 2. MATERIALS AND METHODS 2.1. MaterialsPolyvinyl alcohol was purchased from HiMedia Laboratories - India, and sodium alginate was purchased from Zhanyun Co., Ltd., Shanghai, China. Graphene oxide prepared by the Hummer method was provided by Nano Institute, Phenikaa University, Hanoi. Boric acid, sodium sulfate, hydrochloric acid, and sodium hydroxide were purchased from Sigma Aldrich, USA.Activated sludge was obtained from the Laboratory of the Center for Materials Technology. The sludge used was light brown, settled well, and the MLVSS/MLSS ratio was 0.88.Synthetic wastewater is prepared from the following materials: glucose (C6 H12O6), ammonium chloride (NH4Cl), potassium dihydrogen phosphate (KH2PO4), NaHCO3 and trace chemicals: FeCl3.6H2O; KI; CoCl2.6H2O; H3BO3; MnCl2.4H2O; ZnSO4.7H2O; CuSO4.5H2O and EDTA.2.2. Research method2.2.1. Gel particle formation1g of graphene oxide (GO) was dissolved in 1 L of distilled water by ultrasonication to obtain a dark brown GO solution. The gel solution for gel formation was prepared by dissolving 10 g of PVA powder in 100 mL of distilled water and stirring well. After obtaining a homogeneous solution, 2 g of SA was slowly added to the newly obtained PVA solution. The solution was stirred for 60