Regeneration Potential of Eggshell Adsorbent on Spent Vegetable Oil: A Mean to Achieving Global Sustainability

The regeneration potential of activated eggshell adsorbent (AESA) on spent vegetable oils (SVOs) is a promising approach to realizing global sustainability. Eggshell, which are typically discarded, was converted into an effective adsorbent in removing impurities from spent vegetable oil. This involved the cleaning and drying of eggshell followed by pulverization and chemical treatment for better modification, and improved adsorption capacity. Batch adsorption method was adopted at dosage range of 4 to 20 g at 4 g interval, and optimum time and temperature of 80 min and 50 oC respectively. Oil and adsorbents were mixed using magnetic stirrer and heated for 80 minutes at 50 oC. The adsorbent was separated from the oil by filtration of hot suspension on Buchner’s funnel with filter paper in a vacuum at (10-15 mm Hg) for 2 hours. The cool filtrates were stored in sealed bottles for further analysis. The results revealed that at the optimum dosage of 16 g, the percentage recovery of free fatty acids (FFA) and peroxide (PO) was 91.63 and 87.11 % respectively. The adsorbent was able to turn the dark brown colour of SVOs to golden brown, and the objectionable odour becomes less objectionable. Overall, the adsorbent was able to regenerate the SVOs close to the original status, thereby providing an innovative solution that contributes to global sustainability, by reducing waste, conserving resources, and promoting circular economy.