Valorization of cigarette butts for top value-added chemicals: Levulinic Acid

Levulinic acid (LA), one of the top value-added intermediates of chemical industry, can be obtained by thermal hydrolysis (at 200 °C) from cigarette butts (as cellulose feedstock) catalysed by phosphoric acidic. The protocol avoids the use of more aggressive H2SO4 and HCl, that are generally employed on several cellulose sources (e.g. sludge paper), thus minimizing corrosion phenomena of plants. Neither chemical pre-treatment of butts nor specific purification procedure of LA are required. Notably, by simply modifying acid catalyst (e.g. using CH3COOH), another top value-added fine chemical such as 5-hydroxymethylfuraldehyde (HMF) is obtained, thus widening the scope of the method.Being cigarette filters a waste available in quantities of megatonnes per year, they represent an unlimited at no cost source of cellulose, thus enabling the up-scale to an industrial level of LA production.