Dicationic Ionic Liquids as Environmentally Benign Catalysts for Biodiesel Synthesis

Abstract

Some dicationic ionic liquids, N,N,N′,N′-tetramethyl-N,N′-dipropanesulfonic acid ethylenediammonium hydrogen sulfate, N,N,N′,N′-tetramethyl-N,N′-dipropanesulfonic acid 1,3-propanediammonium hydrogen sulfate, N,N,N′,N′-tetramethyl-N,N′-dipropanesulfonic acid 1,6-hexanediammonium hydrogen sulfate, were prepared. These ionic liquids could be used as efficient and recyclable catalysts for the synthesis of biodiesel from free long-chain fatty acids or their mixtures with low-molecular-weight alcohols as substrates. the reaction was accomplished in a monophase at 70 °C for 6 h, while the products was separated from the catalyst system by liquid/liquid biphase separation at room temperature with good yields of 93−96%. The post processing was simple, and after removal of water, the catalysts could be reused at least six times and the decrease in the yield was 3%. The novel and clean procedure offers advantages including short reaction time, good yield, operational simplicity, and environmentally benign characteristics.

Prospecção Para Obtenção De Biodiesel Empregando Óleo De Babaçu (Orbigynia Martiniana) E De Óleo De Soja (Glycine Max) Utilizando Líquido Iônico Como Catalisador

“…Eles têm apontado como excelentes catalisadores para reações de síntese orgânica, incluindo a transesterificação e esterificação de ácidos graxos (DAS et al, 2014;FANG, YANG, JIAO, 2011) e podem ser facilmente recuperados e reutilizados com baixa geração de subprodutos e ausência de solventes orgânicos (YANG, 2009). …”

Long-chain double SO3H-functionalized Brønsted acidic ionic liquids catalyzed selective alkylation of phenol andp-cresol with tert-butanol

“…BAILs-1 and 2 were synthesized according to previous literatures (20,21). For the synthesis of BAILs-1, tetramethylethylene diamine (0.1 mol) and 1,3-propanesultone (0.21 mol) were dissolved in CH 3 CN (30 mL) and stirred at room temperature for 24 h. On completion, the obtained white solid was filtered off.…”

Use of ionic liquids in biodiesel production: a review

“…Fang et al (2011) synthesized an ionic liquid containing two dialkylsulfonic acid groups with acyclic amines, varying the hydrocarbon chain size between the two nitrogen atoms, as shown in Figure 6 (i). These catalysts were used for the esterification of free fatty acids at 70°C for 6 hours, with a yield of 93 to 96% biodiesel.…”