Chemical and structural changes of pretreated empty fruit bunch (EFB) in ionic liquid-cellulase compatible system for fermentability to bioethanol

The pretreatment of empty fruit bunch (EFB) was conducted using an integrated system of IL and cellulases (IL-E), with simultaneous fermentation in one vessel. The cellulase mixture (PKC-Cel) was derived from Trichoderma reesei by solid-state fermentation. Choline acetate [Cho]OAc was utilized for the pretreatment due to its biocompatibility and biodegradability. The treated EFB and its hydrolysate were characterized by the Fourier transform infrared spectroscopy, scanning electron microscopy, and chemical analysis. The results showed that there were significant structural changes in EFB after the treatment in IL-E system. The sugar yield after enzymatic hydrolysis by the PKC-Cel was increased from 0.058 g/g of EFB in the crude sample (untreated) to 0.283 and 0.62 ± 06 g/g in IL-E system after 24 and 48 h of treatment, respectively. The EFB hydrolysate showed the eligibility for ethanol production without any supplements where ethanol yield was 0.275 g ethanol/g EFB in the presence of the IL, while lower yield obtained without IL-pretreatment. Moreover, it was demonstrated that furfural and phenolic compounds were not at the level of suppressing the fermentation process

Studies on thermal stability of amino acid ionic liquids

Porównano stabilność termiczną soli zbudowanych z aminokwasowego anionu i różnych organicznych kationów. Badania obejmowały ciecze jonowe z kationem: tetrabutyloamoniowym (TBA), tributylometyloamoniowym (tBMA), didecylodimetyloamoniowym (DDA), benzalkoniowym (BA), 2-hydroksyetylotrimetyloamoniowym (Chol) i 1-etylo-3-metyloimidazoliowym (EMIM). Zbadano wpływ kationu na stabilność termiczną dla cieczy z anionem L-leucynianowym, natomiast wpływ budowy aminokwasowego anionu określono dla soli z kationem benzalkoniowym. Dla analizowanych związków, na podstawie analizy termograwimetrycznej (krzywych TG i DTG), wyznaczono temperatury początku rozkładu, temperatury 50% ubytku masy oraz temperatury najszybszego rozkładu związku. Wykazano, że badane aminokwasowe ciecze jonowe mogą być bezpiecznie stosowane do temperatury ok. 140°C. Najwyższą stabilność termiczną wykazywał L-leucynian 1-etylo-3-metyloimidazoliowy. Badania pokazały, że zdecydowanie większy wpływ na stabilność termiczną ma rodzaj kationu. Wykazano ponadto, że pochodne aminokwasów, zawierających w łańcuchu bocznym ugrupowania aromatyczne – indolu (Trp) lub fenolu (Tyr), są termicznie najtrwalsze.We compared the thermal stability of the salt composed of amino acid anions and various organic cations. Studies included cations such as: tetrabutylammonium (TBA), tributylmethylammonium (tBMA), didecylodimethylammonium (DDA), benzalkonium (BA), (2-hydroxyethyl)trimethylammonium (choline) (Chol) and 1-ethyl-3-methylimidazolium (EMIM). We investigated the influence of the cation on the thermal stability of the ionic liquid with L-leucine anion, and the impact of the anion in amino acids ionic liquids with benzalkonium cation. Based on thermogravimetric analysis (TG curves and DTG curves) we determined initial decomposition temperatures, 50% weight loss temperatures and the fastest decomposition temperatures. It has been shown that the amino acid ionic liquids can be safely applied to a temperature of approximately 140°C. The compound with the highest decomposition temperature is 1-ethyl-3-methylimidazolium L-leucinate. Studies showed that type of cation affects on the thermal stability. It was also demonstrated that amino acid derivatives containing the aromatic moieties – indole (in Trp) or phenol (in Tyr), reveal the highest thermally stability

Efficient method for Knoevenagel condensation in aqueous solution of amino acid ionic liquids (AAILs)

This work reports on the use of the amino acid ionic liquids (AAILs) which have been used as catalysts in Knoevenagel condensation of various aldehydes with malononitrile. For research we use tetrabutylammonium ionic liquids based on eight natural amino acids. The reaction was carried out in an aqueous medium. Using water as solvent provided efficient and simple method of isolation of pure product with high yield. Moreover, amino acid ionic liquid dissolved in water could be reused many times without any loss of its catalytic activity. The influence of the anion was studied. Moreover the effect of technological parameters such as: the temperature, the catalyst content, and the reaction time on yield of reaction were investigated