Year: 2024
Type: article
Abstract: Esterification of levulinic acid with ethanol was investigated using deep eutectic systems based on choline chloride and oxalic or p-toluenesulfonic acid as catalysts under conventional heating and alternative energy inputs, namely microwave, ultrasound, and mechanochemical treatment. The experiments were performed under varying operating conditions such as catalyst type and loading, alcohol to carboxylic acid molar ratio, temperature, or time. The obtained results demonstrate the overall better catalytic performance of the p-toluenesulfonic acid-based deep eutectic mixture in comparison with the oxalic acid-based analogue. The best results: levulinic acid conversion of 76% and 58%, for p-toluenesulfonic and oxalic acid containing deep eutectic systems, respectively, with 100% selectivity for both cases, were achieved for microwave-assisted synthesis with 5 wt.% of catalyst and excess alcohol to acid (molar ratio 5), at 413.15 K and for 10 min. The main advantage of all of the alternative activation methods studied (microwaves, ultrasounds, and ball mill processing) was the significant reduction in the reaction time.
Source: Catalysts
Language: English
Subfield: Biomedical Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $3,069
Awards: G1240268737, G138060719, G1509028180, G1522114529, G1977608718, G2012127377, When solids become liquids: natural deep eutectic solvents for chemical process engineering, G2339299466, G2346795057, Laboratório Associado para a Química Verde - Tecnologias e Processos Limpos, Laboratório Associado para a Química Verde - Tecnologias e Processos Limpos, G2756637201, G2783038177, G2814222956, G3127682330, G332082475, G4046065984, G434337789, G4378797157, G4823118686, G567200461, G5868090805, G6113984419, G6119126181, G6463117426, G6997658380, G7609414147, G7613298549, G7786427436, G8213652065, G824076568, G8708718943, Laboratório Associado para a Química Verde - Tecnologias e Processos Limpos, G8963217260
OpenAlex ID: W4404586721