Kinetic and chemical studies on the isomerization of monosaccharides in N-methylmorpholine-N-oxide (NMMO) under Lyocell conditions.
The Lyocell process is a modern and environmentally fully compatible industrial fiber-making technology. Cellulosic pulp is dissolved without chemical derivatization in a melt of N-methylmorpholine-N-oxide monohydrate (NMMO). In the present work, the reactions of monosaccharides under Lyocell conditions were investigated in detail, using capillary zone electrophoresis as the analytical technique to clarify the composition of reaction mixtures and to follow the kinetics. Under Lyocell conditions, xylose and glucose undergo two competitive reactions: rapid conversion to nonreducing products, and complete isomerization involving the whole carbohydrate backbone, via ketose intermediates. Sugar acids are present in minor amounts only, as demonstrated by employing isotopically labeled material for NMR techniques.
Adorjan
Immanuel
I
Christian-Doppler-Laboratory, Department of Chemistry, University of Natural Resources and Applied Life Sciences (BOKU), Muthgasse 18, A-1190 Vienna, Austria.
Sjöberg
John
J
Rosenau
Thomas
T
Hofinger
Andreas
A
Kosma
Paul
P
D002236:Carbohydrate Conformation; D002241:Carbohydrates / Q000737:chemistry; D002247:Carbon Isotopes; D003497:Cyclic N-Oxides / Q000737:chemistry*; D019075:Electrophoresis, Capillary / Q000379:methods; D005947:Glucose / Q000737:chemistry; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy; D009005:Monosaccharides / Q000737:chemistry*; D009025:Morpholines / Q000737:chemistry*; D013237:Stereoisomerism; D013997:Time Factors; D014994:Xylose / Q000737:chemistry
D002241:Carbohydrates; D002247:Carbon Isotopes; D003497:Cyclic N-Oxides; D009005:Monosaccharides; D009025:Morpholines; D014994:Xylose; C067960:4-methylmorpholine N-oxide; D005947:Glucose