Preparation of Zinc Oxide from Used Batteries as a Catalyst in the Transesterification of Recycled Oil for the Production of Biodiesel

Nowadays, batteries and cooking oil consumption has been increasing in Ecuador. This is a big problem because the vast majority of used batteries are disposed of in landfills or in the trash; due to their composition, health and environmental problems are produced. Also, used cooking oil usually is disposed of in rivers and sewers, polluting water, and soil. For these reasons, the circular economy has been raised through the use of these environmental passives. Zinc oxide was obtained from spent batteries with a hydrometallurgical method to later be used as a catalyst. Zinc oxide showed a 98.49% purity, 56.20% of yield and a white coloration. Biodiesel was produced with treated recycled cooking oil, alcohol, and the obtained catalyst. Prepared biodiesel had a heating power of 37.553 kJ/g, a density of 0.8916 g/cm3, a viscosity of 4.1887 mm2/s, a water content of 0.001% and a 70.91% yield.