Biodiesel offers a promising solution to the need for cleaner alternatives to fossil fuels, but the high cost of biodiesel production and potential pollution from biomass sources have prevented its widespread use. Now, researchers at Kaunas University of Technology (KTU) and the Lithuanian Energy Institute (LEI) have found a novel solution by incorporating a by-product of cigarette waste recycling into the production process. It’s estimated that over 6.5 trillion cigarettes are purchased worldwide annually, creating an enormous amount of cigarette waste. This new approach could provide a solution to repurpose this waste and demonstrates the potential for scalable implementation in waste management systems.
“Triacetin, a key compound used in the production of biodiesel, is abundant in cigarette filters,” said Samy Yousef, a chief researcher at KTU Faculty of Mechanical Engineering and Design.
The team was able to successfully extract valuable components from cigarette waste through a series of experiments using pyrolysis – a thermal decomposition process. The process was conducted at varying temperatures, and yielded oil, char, and gas from the waste, with oil content notably rich in triacetin. The largest quantity of triacetin (43%) was synthesized at 750°C. This oil could be integrated as an additive in biodiesel production, potentially reducing production costs and increasing efficiency.
The process would also address the environmental impact of cigarette waste and harvest its components for practical applications. The porous char produced, when enriched with calcium, has the potential for fertilizers, wastewater treatment, and energy storage applications. The gas extracted could be an energy source.
“In our research group, we are working on the topics of recycling and waste management, therefore we are always looking for the waste, which is present in huge amounts and has a unique structure. Cigarettes are made of three components – tobacco, paper and a filter made of cellulose acetate fibers – and are a good source of raw materials and energy. Plus, cigarette butts are easy to collect as there are many systems and companies for collecting this waste in place,” stated Yousef.