Production of candles from waste cooking oil

Abstract

Waste cooking oil is generated in large amount all over the world. Hence, it has devised serious problems on its waste management. Disposal of waste cooking oil by pouring it into the drain and watercourse will result in pipes clogging and destruction towards wastewater and septic system besides polluting the environment. Therefore, production of candles is the latest approach of efficient waste management and utilization of waste product across the globe. In the present work, candles were produced by mixing 100 ml of waste cooking oil (originated from palm oil) with different amounts (10 g, 15 g, 20 g, 25 g and 30 g) of candle palm wax powder. Besides, the effects of different additives such as polyethylene, stearic acid and microcrystalline wax to the candles were studied and compared. Hardness of the candles was evaluated using texture analyzer (Stable Micro Systems) while the burning characteristics such as burning periods, burn rates, flame sizes and pool diameters of the candles were studied by letting the candles burn for 6 hours. Adding microcrystalline wax to the candles improved both the hardness and burning properties of the candles. Adding polyethylene and stearic acid decreased the hardness and burning performance of the candles due to the fluidity of the candles which couldn’t be solidified. However, adding stearic acid into the candles with 25 g and 30 g candle palm wax improved the hardness of the candles due to the lower fluidity in the candles. Changing the candle palm wax composition and inconsistent of the temperature of pouring the melted wax to the container as well as the tightness of the wick in the candles resulted in candles with desirable quality attributes.