Investigation of wastewater treatment using waste materials and algae through carbonization and activation processes

Abstract

Clean drinking water is one of the most important issues in the world and will be one of the most studied subjects together with food in the near future. Some freshwater sources are contaminated with sulfur, nitrogen, phosphorous, and other organic and inorganic contaminants. Desalination, a solution to this wastewater problem, is a costly and time-consuming process. The objective of this study was to develop a cheaper and sustainable process for cleaning lakes and other drinking water sources using waste materials. In this study, algae, clothes, waste paper, and fruit waste, such as date and olive seeds, were used to produce activated carbons (ACs). These materials were briquetted under high pressure using different amounts of molasses as a binder. Date and olive seeds were crushed, sieved, and dried prior to the briquetting process. Chemical activation of the seed briquettes was performed using zinc chloride (ZnCl2) and calcium chloride (CaCl2). Following chemical activation, carbonization in an inert atmosphere was performed to prepare the proper samples. The pH adjustments were applied after the chemical activation and carbonization processes. Additionally, Brunauer-Emmett-Teller (BET) and scanning electron microscopy (SEM) tests were performed to determine the surface area, morphology, and porosity of the produced ACs. This is a promising technique to clean wastewater; activated carbons are expected to remove nitrogen, phosphorus, sulfur, and other contaminants from wastewater. The produced ACs were used to build a water column filter. Water quality was investigated before and after filtration. It was observed that after filtering using AC, the water became suitable for drinking.