Baú, AnaLenzi, Giane G.Ribeiro, António E.Queiroz, AnaBrito, Paulo2020-02-212020-02-212018Baú, Ana; Lenzi, Giane G.; Ribeiro, António E.; Queiroz, A.M.; Brito, Paulo (2018). Acidic waste cooking oil valorization by biodiesel synthesis catalyzed by hydrogen sulfate 1-butyl-3-methylimidazolium. In XXIV Encontro Luso-Galego de Química. Portohttp://hdl.handle.net/10198/20653Biodiesel is a fuel that shows growing demand as a promising alternative to petroleum-derived fuels. It is produced by esterification or transesterification reactions from renewable raw materials such as animal fats and vegetable oils , where the presence of catalysts is used for an effective conversion. The basic catalysts are very sensitive to the presence of water and FFAs, promoting saponification reactions. On the other hand, the use of acid catalysts means reaction times up to 4000 times higher, higher alcohol/oil molar ratios and higher reaction temperatures. In this context, Ionic Liquids (ILs) used as catalysts, come as a viable alternative to overcome these problems in biodiesel production processes. Imidazolium-based ILs, have been extensively studied, mainly due to their specific characteristics such as, low pressure and ability for self-organization in different states.engconference poster