Preparation of discarded cigarette butt-derived activated carbon and its decolorization for waste edible oils

In order to improve the high added values and solve the environmental pollution problems of the waste edible oil (EO) and discarded cigarette butt (CB), the CB-derived activated carbons (ACs) were prepared by H₃PO₄, KOH, and CO₂ activation methods and used as an adsorbent for the decolorization of waste EO. The CB-AC@H₃PO₄ prepared by H₃PO₄ activation method had the high surface area of 1423 m²/g, oxygen contents of 11.24%, and yield of 14.11%, and exhibited better decolorization performance for EO than the CB-AC@KOH and CB-AC@CO₂. The optimal decolorization process parameters of CB-AC@H₃PO₄ based on the orthogonal experimental results were the AC contents of 8%, the decolorization temperature of 90 °C, and the decolorization time of 30 min, which resulted in the corresponding decolorization rate of 83%. Therefore, these provided one application case for turning waste into wealth, energy conservation, and emission reduction.