Mild electrocatalytic hydrogenation of lactic acid to lactaldehyde and propylene glycol

Tulika S. Dalavoy, James E. Jackson, Greg M. Swain, Dennis J. Miller, Jie Li, Jacek Lipkowski

Research output: Contribution to journalArticle

  • 22 Citations

Abstract

Reduction of fermentation-derived lactic acid (LA) offers a renewables-based pathway to propylene glycol (PG), a large-scale commodity chemical, currently manufactured by the oxidation of petroleum-derived propene. Complementing our previously described catalytic hydrogenation of LA to PG, we now report electrocatalytic hydrogenation (ECH) of LA in an aqueous electrolyte using constant current electrolysis. A reticulated vitreous carbon (RVC) electrode serves to agglomerate, support, and supply current to a 5% Ru/C powder catalyst, the same catalyst used in the classical hydrogenations. The ECH conditions are mild (ambient pressure, 70 °C vs 1500 psi H2, 150 °C) relative to the chemical hydrogenation. More surprisingly, the major electrohydrogenation product is lactaldehyde (LAL), with small quantities of PG also formed. Variable current studies in the range of 10-100 mA show an increase in product yields and a shift in selectivity toward PG with increasing current. Experiments carried out with different acids as electrolytes reveal a distinct effect of the anion on the yields of the two products. In situ ATR-FTIR studies of the ECH of LA point to a chelating bidentate carboxylate adsorption mode for lactate on the Ru surface and offer insight into the effects of electrolyte anions on surface adsorption and reactivity.

LanguageEnglish (US)
Pages15-28
Number of pages14
JournalJournal of Catalysis
Volume246
Issue number1
DOIs
StatePublished - Feb 15 2007

Profile

Propylene Glycol
lactic acid
Lactic acid
Glycols
propylene
Hydrogenation
hydrogenation
Propylene
glycols
Lactic Acid
Electrolytes
electrolytes
Anions
Negative ions
products
anions
Adsorption
catalysts
commodities
lactates

Keywords

  • ATR
  • Electrocatalytic hydrogenation
  • Electrosynthesis
  • FTIR
  • Green chemistry
  • Lactaldehyde
  • Lactic acid
  • Organic electrochemistry
  • Propylene glycol
  • Reticulated vitreous carbon
  • SEIRAS

ASJC Scopus subject areas

  • Catalysis
  • Process Chemistry and Technology

Cite this

Mild electrocatalytic hydrogenation of lactic acid to lactaldehyde and propylene glycol. / Dalavoy, Tulika S.; Jackson, James E.; Swain, Greg M.; Miller, Dennis J.; Li, Jie; Lipkowski, Jacek.

In: Journal of Catalysis, Vol. 246, No. 1, 15.02.2007, p. 15-28.

Research output: Contribution to journalArticle

@article{5e0c4ff7b3524ef3b132b56d316107b0,
title = "Mild electrocatalytic hydrogenation of lactic acid to lactaldehyde and propylene glycol",
abstract = "Reduction of fermentation-derived lactic acid (LA) offers a renewables-based pathway to propylene glycol (PG), a large-scale commodity chemical, currently manufactured by the oxidation of petroleum-derived propene. Complementing our previously described catalytic hydrogenation of LA to PG, we now report electrocatalytic hydrogenation (ECH) of LA in an aqueous electrolyte using constant current electrolysis. A reticulated vitreous carbon (RVC) electrode serves to agglomerate, support, and supply current to a 5{\%} Ru/C powder catalyst, the same catalyst used in the classical hydrogenations. The ECH conditions are mild (ambient pressure, 70 °C vs 1500 psi H2, 150 °C) relative to the chemical hydrogenation. More surprisingly, the major electrohydrogenation product is lactaldehyde (LAL), with small quantities of PG also formed. Variable current studies in the range of 10-100 mA show an increase in product yields and a shift in selectivity toward PG with increasing current. Experiments carried out with different acids as electrolytes reveal a distinct effect of the anion on the yields of the two products. In situ ATR-FTIR studies of the ECH of LA point to a chelating bidentate carboxylate adsorption mode for lactate on the Ru surface and offer insight into the effects of electrolyte anions on surface adsorption and reactivity.",
keywords = "ATR, Electrocatalytic hydrogenation, Electrosynthesis, FTIR, Green chemistry, Lactaldehyde, Lactic acid, Organic electrochemistry, Propylene glycol, Reticulated vitreous carbon, SEIRAS",
author = "Dalavoy, {Tulika S.} and Jackson, {James E.} and Swain, {Greg M.} and Miller, {Dennis J.} and Jie Li and Jacek Lipkowski",
year = "2007",
month = "2",
day = "15",
doi = "10.1016/j.jcat.2006.11.009",
language = "English (US)",
volume = "246",
pages = "15--28",
journal = "Journal of Catalysis",
issn = "0021-9517",
publisher = "Academic Press Inc.",
number = "1",

}

TY - JOUR

T1 - Mild electrocatalytic hydrogenation of lactic acid to lactaldehyde and propylene glycol

AU - Dalavoy,Tulika S.

AU - Jackson,James E.

AU - Swain,Greg M.

AU - Miller,Dennis J.

AU - Li,Jie

AU - Lipkowski,Jacek

PY - 2007/2/15

Y1 - 2007/2/15

N2 - Reduction of fermentation-derived lactic acid (LA) offers a renewables-based pathway to propylene glycol (PG), a large-scale commodity chemical, currently manufactured by the oxidation of petroleum-derived propene. Complementing our previously described catalytic hydrogenation of LA to PG, we now report electrocatalytic hydrogenation (ECH) of LA in an aqueous electrolyte using constant current electrolysis. A reticulated vitreous carbon (RVC) electrode serves to agglomerate, support, and supply current to a 5% Ru/C powder catalyst, the same catalyst used in the classical hydrogenations. The ECH conditions are mild (ambient pressure, 70 °C vs 1500 psi H2, 150 °C) relative to the chemical hydrogenation. More surprisingly, the major electrohydrogenation product is lactaldehyde (LAL), with small quantities of PG also formed. Variable current studies in the range of 10-100 mA show an increase in product yields and a shift in selectivity toward PG with increasing current. Experiments carried out with different acids as electrolytes reveal a distinct effect of the anion on the yields of the two products. In situ ATR-FTIR studies of the ECH of LA point to a chelating bidentate carboxylate adsorption mode for lactate on the Ru surface and offer insight into the effects of electrolyte anions on surface adsorption and reactivity.

AB - Reduction of fermentation-derived lactic acid (LA) offers a renewables-based pathway to propylene glycol (PG), a large-scale commodity chemical, currently manufactured by the oxidation of petroleum-derived propene. Complementing our previously described catalytic hydrogenation of LA to PG, we now report electrocatalytic hydrogenation (ECH) of LA in an aqueous electrolyte using constant current electrolysis. A reticulated vitreous carbon (RVC) electrode serves to agglomerate, support, and supply current to a 5% Ru/C powder catalyst, the same catalyst used in the classical hydrogenations. The ECH conditions are mild (ambient pressure, 70 °C vs 1500 psi H2, 150 °C) relative to the chemical hydrogenation. More surprisingly, the major electrohydrogenation product is lactaldehyde (LAL), with small quantities of PG also formed. Variable current studies in the range of 10-100 mA show an increase in product yields and a shift in selectivity toward PG with increasing current. Experiments carried out with different acids as electrolytes reveal a distinct effect of the anion on the yields of the two products. In situ ATR-FTIR studies of the ECH of LA point to a chelating bidentate carboxylate adsorption mode for lactate on the Ru surface and offer insight into the effects of electrolyte anions on surface adsorption and reactivity.

KW - ATR

KW - Electrocatalytic hydrogenation

KW - Electrosynthesis

KW - FTIR

KW - Green chemistry

KW - Lactaldehyde

KW - Lactic acid

KW - Organic electrochemistry

KW - Propylene glycol

KW - Reticulated vitreous carbon

KW - SEIRAS

UR - http://www.scopus.com/inward/record.url?scp=33846203236&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=33846203236&partnerID=8YFLogxK

U2 - 10.1016/j.jcat.2006.11.009

DO - 10.1016/j.jcat.2006.11.009

M3 - Article

VL - 246

SP - 15

EP - 28

JO - Journal of Catalysis

T2 - Journal of Catalysis

JF - Journal of Catalysis

SN - 0021-9517

IS - 1

ER -