Stricter environmental norms and fossil fuel pollution call for cleaner fuels such as biodiesel. This vegetable oil- or animal fat-based diesel is biodegradable—up to four times faster than petroleum diesel—and nontoxic. However, the high production cost of biodiesel remains a major barrier to its wider applicability, and, depending on the biomass source, using it may cause pollution. Adding a blender such as a triacetin compound, can solve both of these issues, according to research. Unfortunately, triacetin is usually produced chemically, consuming a lot of chemicals, and resulting in waste and toxic residues.
“Triacetin is used as a plasticizer in cigarettes’ filter, so, naturally, cigarette butts are rich in it,” says Samy Yousef, a chief researcher at Kaunas University of Technology, Lithuania. Together with his colleagues from the Lithuanian Energy Institute (LEI), he conducted a series of experiments where they used pyrolysis to thermally decompose cigarette waste. The experiments were carried out in a 200 g reactor at different reaction temperatures (650, 700, and 750°C). The biggest quantity of triacetin (43%) was synthesized at 750°C.
Cigarette butts’ collection systems, e.g., metal wastebaskets and ashtrays, are used widely to collect them separately from solid waste. As for the recycling strategy, the researchers propose using pyrolysis treatment at 750°C, which thermally converts cigarette butts into char, gas, and oil. Gaseous products can be used to generate electricity and to power the conversion plant, char can be used as absorbents, while oil can be added to biofuels at a rate of up to 25% since the allowable triacetin rate is 10%.
Source: European Commission