Therefore, it is important to detect and remove cobalt (II) ions from wastewater prior to their discharge into the environment. While cobalt ions are biologically necessary and an essential component vitamin B12 and cobalamins which play role in red blood cells production, the exposure to high level of (Co2+)has been reported to cause various health effects such vomiting, nausea, paralysis, vision problem, lung irritation, sterility, hair loss, thyroid, low blood pressure, bone defects and diarrhea. Like other heavy metals, most of cobalt ions find their way into the environment through waste waters discharged from nuclear power plants as well as mining, electroplating, pigment, metallurgical, electronic and paint industries. Keywords: Extraction, red onion skin, azo dyes, quercetin, Co2+ ions.Д¬obalt ion (Co2+) is among inorganic compounds formed from metals known as transitional metals. The slope analysis carried out on the experimental data demonstrated that Co2+ions reacted with the ligands in 1:2 metals to ligand ratio. The results also showed that the % extraction (% E) of Co2+ions increased with agitation time and concentration of the ligand. The highest removal efficiencies were obtained within the pH ranges 6-7. The study revealed that the azo dyes were effective in removing Co2+ ion from aqueous solution. The effect of pH, agitation time, ligand concentration, and metal ion concentration on Co2+ ions removal efficiency as well as the stoichiometric coefficients were examined. Uche John Chukwu 3ДЎ Chemistry Department, College of Science and Technology, University of Rwanda, RwandaДўChemical Engineering Department, African Center of Excellence for Sustainable Mining, Copperbelt University, ZambiaДЈPure and Industrial Chemistry Department, University of Port Harcourt, NigeriaДЄbstract: The present study investigated the synthesis of low cost and environmental friendly red onion skins azo dyes derivatives and their application as ligands for the extraction of cobalt (II) ions from aqueous media. Gervais Manizabayo 1*, Aimable Niyomugabo 2, Dr. Synthesis and Application of Eco-Friendlyred Onion Skins Azo Dyes for The Removal of Cobalt from Aqueous Media International Journal of Research and Innovation in Applied Science (IJRIAS) | Volume VI, Issue VII, July 2021|ISSN 2454-6194

Analysis synthesis and application