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We report here the synthesis, characterization, and use of tin (3‐hydroxy‐2‐methyl‐4‐pyrone)2(H2O)2, lead (3‐hydroxy‐2‐methyl‐4‐pyrone)2 (H2O)2, mercury (3‐hydroxy‐2‐methyl‐4‐pyrone)2‐(H2O)2, and zinc (3‐hydroxy‐2‐methyl‐4‐pyrone)2(H2O)2 as catalysts in the transesterification reaction of soybean oil with methanol. All complexes are active in this reaction, with the following decreasing activities: Sn2+≫Zn2+>Pb2+≈Hg2+. The catalytic activities of these complexes were also compared with classical alkali and acid transesterification catalysis (with NaOH and H2SO4).

Neste trabalho são apresentados a preparação de novos materiais obtidos da co-precipitação de alumina e óxidos de estanho e zinco e seu uso como sistemas catalíticos ativos para alcoólise de óleos vegetais. Foi observado que estes óxidos metálicos do tipo (Al 2 O 3 ) X (SnO) Y (ZnO) Z são ativos para a alcoólise do óleo de soja usando diversos álcoois, incluindo ramificados. Os melhores resultados foram observados utilizando metanol, sendo atingidas conversões acima de 80% em 4 horas. Foi também possível reciclar estes materiais sem perda aparente de sua atividade catalítica.The preparation of new materials obtained from the co-precipitation of aluminum, tin and zinc oxides and their use as catalytic system activities for vegetable oils alcoholysis are reported herein. It was observed that these metal-oxides of the type (Al 2 O 3 ) X (SnO) Y (ZnO) Z are active for soybean oil alcoholysis, uzing several alcohols, including branched ones. Best result was achieved using methanol, with conversion yields up to 80% in 4 h. It was also possible to recycle the catalysts without apparent loss of activity.

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