Utilization of magnetic silica as tofu wastewater treatment absorber (influence of mass and adsorption time)

Abstract

AbstractWastewater from tofu production generally has many pollutant parameters, such as nitrogen, phosphorus, turbidity, and total suspended solids (TSS). These pollutants can cause a decrease in oxygen levels and pollute water bodies. This study aims to determine changes in pH and removal efficiency of turbidity and TSS in tofu wastewater using the size of 80 mesh magnetic silica. The research used a laboratory-scale batch system with variations in the absorbent mass of 5 g, 7.5 g, and 10 g per 1 liter of tofu wastewater and adsorption times of 15, 30, 45, and 60 minutes. The stirring speed used is 100 rpm, and the operating temperature is adjusted to the laboratory temperature. As a result, the TSS removal has the most effective results of 80%, with 7.5 g of magnetic silica added per liter of wastewater and 45 minutes of adsorption time with a TSS value of 90 mg/L. Meanwhile, the optimum turbidity removal was 82.52% with 7.5 g adsorbent and adsorption time of 15 minutes resulting in a turbidity value of 82.1 NTU. The resulting pH varies in the range of 3.28-4.27, depending on the mass of the adsorbent and the adsorption time.