6533b826fe1ef96bd12846ca
RESEARCH PRODUCT
Alkaline Pre-treatment of Hardwood Chips Prior to Delignification
Joni LehtoRaimo Alénsubject
chemistry.chemical_classificationAqueous solutionGeneral Chemical EngineeringGeneral ChemistryPolysaccharideAlkali metalHydrolysatechemistry.chemical_compoundchemistryHardwoodDegradation (geology)Organic chemistryMonosaccharideLigninGeneral Materials Scienceta116description
Scots pine (Pinus sylvestris) chips were pre-treated with alkaline solutions (alkali charges of 1, 2, 3, 4, 6, and 8% of NaOH on the oven-dried wood material) at 130°C and 150°C for various treatment times (30, 60, 90, and 120 minutes). Under these conditions, 2.0–13.6% of the wood d.s. was dissolved into the aqueous hydrolysates. The soluble organic fraction was primarily characterized in terms of carbohydrates (monosaccharides and oligo-/polysaccharides) and their alkali-catalyzed degradation products: aliphatic carboxylic acids containing, besides non-volatile hydroxy carboxylic acids, volatile formic and acetic acids. With increasing alkali charge, temperature, and time, the enhanced formation of various hydroxy monocarboxylic acids was detected. Under the most drastic pre-treatment conditions, two-thirds of the total organic fraction dissolved was composed of various aliphatic carboxylic acids, the residual material being mainly degraded lignin and extractives. Only relatively small concentrations of...
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2013-06-01 | Journal of Wood Chemistry and Technology |