Cascade Production of Lactic Acid from Universal Types of Sugars Catalyzed by Lanthanum Triflate

Journal Article · 16 January 2018 · ChemSusChem

DOI: https://doi.org/10.1002/cssc.201701902 · OSTI ID:1417216

Liu, Dajiang ^[1]; Kim, Kwang Ho ^[1]; Sun, Jian ^[1]; Simmons, Blake A. ^[2]; Singh, Seema ^[3]

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1. Deconstruction Division Joint BioEnergy Institute Emeryville CA 94608 USA, Biomass Science and Conversion Technology Department Sandia National Laboratories Livermore CA 94551 USA
2. Deconstruction Division Joint BioEnergy Institute Emeryville CA 94608 USA, Biological Systems and Engineering Division Lawrence Berkeley National Laboratory Berkeley CA 94720 USA
3. Deconstruction Division Joint BioEnergy Institute Emeryville CA 94608 USA, Biomass Science and Conversion Technology Department Sandia National Laboratories Livermore CA 94551 USA, Department of Bioproducts and Biosystems Engineering University of Minnesota St. Paul MN 55108 USA

Abstract Lignocellulosic biomass conversion into value‐added platform chemicals in the non‐toxic, water‐tolerant Lewis acid, and water solutions bears the hallmark of green chemistry. Lactic acid derived from biomass is an important chemical building block for biodegradable polymers such as polylactide. Herein, a universal method of converting lignocellulosic sugars into lactic acid using catalytic amount of water‐stable Lewis acid La(OTf) ₃ is demonstrated. The lignocellulosic sugars studied in this work include 1) pyrolytic sugars from pyrolysis oil, and 2) sugars derived from ionic liquid (IL)‐pretreated biomass. Under moderate conditions (250 °C, 1 h), levoglucosan (major pyrolytic sugar), glucose, and xylose were converted into lactic acid with carbon‐based molar yields of 75, 74, and 61 %, respectively. Furthermore, roughly 49 mol % (based on levoglucosan) and 74 wt % (relative to pretreated biomass) of lactic acid were obtained from the conversion of pyrolytic sugars and sugar‐rich fraction after lignin removal from switchgrass, respectively. To our knowledge, this is the first reported conversion of pyrolytic sugar into lactic acid by chemocatalysis and also lignocellulosic sugars are converted into lactic acid without hydrolysis. This approach could potentially be extended to other lignocellulosic sugars after simple removal of lignin from biomass pretreatment, rendering moderate to high yields of lactic acid.

• Sponsoring Organization: USDOE
• Grant/Contract Number: AC02-05CH11231
• OSTI ID: 1417216
• Journal Information: ChemSusChem, Journal Name: ChemSusChem Journal Issue: 3 Vol. 11; ISSN 1864-5631
• Publisher: Wiley Blackwell (John Wiley & Sons)Copyright Statement
• Country of Publication: Germany
• Language: English