Details

Autor(en) / Beteiligte

• Shi, Shengbin
• Wu, Yuanfeng
• Zhang, Mengting
• Zhang, Zongqi
• Oderinde, Olayinka
• Gao, Lijing
• Xiao, Guomin

Titel

Direct conversion of cellulose to levulinic acid using SO3H-functionalized ionic liquids containing halogen-anions

Ist Teil von

• Journal of molecular liquids, 2021-10, Vol.339, p.117278, Article 117278

Ort / Verlag

Elsevier B.V

Erscheinungsjahr

2021

Link zum Volltext

Quelle

ScienceDirect

Beschreibungen/Notizen

• SO3H-Functionalized ionic liquids containing halogen-anions were successfully synthesized and used as catalyst for conversion of biomass to levulinic acid, a high levulinic acid yield of 76.5% was achieved when used cellulose as substrates. [Display omitted] •Synthesis and characterization of SO3H-functionalized ionic liquids containing halogen-anions.•The yield of LA is up to 76.5% at reaction time of 20 min with using [BSim]Br as catalyst.•The [BSim]Br was easily recycled and showed high catalytic activity even after four cycles.•The yield of LA were dependent on the anions and in the order of increase: F- ＜ Cl- ＜ Br-. The conversion of cellulose to levulinic acid (LA) and other platform chemicals is a promising route to solve the energy crisis. For this purpose, a series of new SO3H-functionalized ionic liquids (ILs), containing different halogen-anions were synthesized and applied for catalytic conversion of cellulose to LA. The structure, thermal stability, and acidity of SO3H-functionalized ILs were characterized by Nuclear magnetic resonance (NMR) spectra, Fourier-transform infrared (FT-IR), High resolution mass spectrometry (HRMS), thermogravimetric analysis (TGA), and Hammet acidity method. The results revealed that as the size of halogen anions increased, the Hammett acidity gradually increased from SO3H-functionalized ILs containing fluorine- to chlorine- and then to bromine-anions. When SO3H-functionalized ILs were used as a catalyst for the production of LA from cellulose, the yield of LA gradually increased as the size of halogen-anions increased from fluorine- to chlorine- and then to bromine-anions. Among the SO3H-functionalized ILs, 1,1-bis(3-(4-sulfobutyl)imidazolium-1-yl)butylene bromine ([BSim]Br) exhibited the best catalytic activity with 76.5% yield of LA in cellulose/[BSim]Br/H2O (m/m/m = 1:9:8) reaction system at 180 °C for 20 min, which was the highest yield compared to previous literature reports using ILs as catalyst. Besides, the [BSim]Br was easily recovered and showed high catalytic activity after five cycles. The efficient catalyst, [BSim]Br is then proposed to have a great potential for mass production of LA from biomass.