Catalysed alkaline oxidation as a wood fractionation technique

Stella Rovio, Anne Kallioinen, Tarja Tamminen, Maija Hakola, Markku Leskelä, Matti Siika-aho

Research output: Contribution to journalArticleScientificpeer-review

15 Citations (Scopus)

Abstract

Alkaline oxidation (AlkOx) is an effective fractionation technique for lignocellulosic raw materials. The efficiency of the AlkOx treatment can further be enhanced by using a catalyst (CatOx). Both CatOx and AlkOx provide a fiber fraction containing readily hydrolysable carbohydrates that can be utilized in biotechnical processes and a liquid fraction containing solubilized lignin and reaction products from various biomass components. The effects of different fractionation conditions on yields and chemical composition of solubilized and insoluble fractions were investigated. Two temperatures and two reaction times were studied with and without a catalyst. The composition and content of carbohydrates in the fiber and liquid fractions were examined. The generation of aliphatic carboxylic acids as oxidation products was also investigated. The catalytically assisted oxidation was more efficient than the alkaline counterpart in dissolution of wood components under a four-hour treatment period resulting in higher dissolution of hemicelluloses. A longer reaction time of 20 hours leveled out the differences between the oxidation processes. Comparison of different bases showed that similar solubilisation of dry matter was obtained with NaOH, KOH, and Na2CO3. Oxidation in Na2CO3 caused higher dissolution of glucomannan and greater acid production. The dissolution of hemicellulose and lignin, and their oxidation to acids was most efficient in the first 4 hours of oxidation.
Original languageEnglish
Pages (from-to)756-776
Number of pages20
JournalBioResources
Volume7
Issue number1
Publication statusPublished - 2012
MoE publication typeA1 Journal article-refereed

Fingerprint

Fractionation
Wood
fractionation
oxidation
Oxidation
Dissolution
dissolution
Lignin
Carbohydrates
lignin
carbohydrate
catalyst
Catalysts
liquid
Acids
Fibers
acid
Liquids
solubilization
carboxylic acid

Keywords

  • Catalysis
  • alkaline oxidation
  • chromatography
  • capillary electrophoresis
  • spruce
  • pretreatment
  • fractionation

Cite this

Rovio, S., Kallioinen, A., Tamminen, T., Hakola, M., Leskelä, M., & Siika-aho, M. (2012). Catalysed alkaline oxidation as a wood fractionation technique. BioResources, 7(1), 756-776.
Rovio, Stella ; Kallioinen, Anne ; Tamminen, Tarja ; Hakola, Maija ; Leskelä, Markku ; Siika-aho, Matti. / Catalysed alkaline oxidation as a wood fractionation technique. In: BioResources. 2012 ; Vol. 7, No. 1. pp. 756-776.
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abstract = "Alkaline oxidation (AlkOx) is an effective fractionation technique for lignocellulosic raw materials. The efficiency of the AlkOx treatment can further be enhanced by using a catalyst (CatOx). Both CatOx and AlkOx provide a fiber fraction containing readily hydrolysable carbohydrates that can be utilized in biotechnical processes and a liquid fraction containing solubilized lignin and reaction products from various biomass components. The effects of different fractionation conditions on yields and chemical composition of solubilized and insoluble fractions were investigated. Two temperatures and two reaction times were studied with and without a catalyst. The composition and content of carbohydrates in the fiber and liquid fractions were examined. The generation of aliphatic carboxylic acids as oxidation products was also investigated. The catalytically assisted oxidation was more efficient than the alkaline counterpart in dissolution of wood components under a four-hour treatment period resulting in higher dissolution of hemicelluloses. A longer reaction time of 20 hours leveled out the differences between the oxidation processes. Comparison of different bases showed that similar solubilisation of dry matter was obtained with NaOH, KOH, and Na2CO3. Oxidation in Na2CO3 caused higher dissolution of glucomannan and greater acid production. The dissolution of hemicellulose and lignin, and their oxidation to acids was most efficient in the first 4 hours of oxidation.",
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author = "Stella Rovio and Anne Kallioinen and Tarja Tamminen and Maija Hakola and Markku Leskel{\"a} and Matti Siika-aho",
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Rovio, S, Kallioinen, A, Tamminen, T, Hakola, M, Leskelä, M & Siika-aho, M 2012, 'Catalysed alkaline oxidation as a wood fractionation technique', BioResources, vol. 7, no. 1, pp. 756-776.

Catalysed alkaline oxidation as a wood fractionation technique. / Rovio, Stella; Kallioinen, Anne; Tamminen, Tarja; Hakola, Maija; Leskelä, Markku; Siika-aho, Matti.

In: BioResources, Vol. 7, No. 1, 2012, p. 756-776.

Research output: Contribution to journalArticleScientificpeer-review

TY - JOUR

T1 - Catalysed alkaline oxidation as a wood fractionation technique

AU - Rovio, Stella

AU - Kallioinen, Anne

AU - Tamminen, Tarja

AU - Hakola, Maija

AU - Leskelä, Markku

AU - Siika-aho, Matti

N1 - Project code: 258311 (SA-Cadewo)

PY - 2012

Y1 - 2012

N2 - Alkaline oxidation (AlkOx) is an effective fractionation technique for lignocellulosic raw materials. The efficiency of the AlkOx treatment can further be enhanced by using a catalyst (CatOx). Both CatOx and AlkOx provide a fiber fraction containing readily hydrolysable carbohydrates that can be utilized in biotechnical processes and a liquid fraction containing solubilized lignin and reaction products from various biomass components. The effects of different fractionation conditions on yields and chemical composition of solubilized and insoluble fractions were investigated. Two temperatures and two reaction times were studied with and without a catalyst. The composition and content of carbohydrates in the fiber and liquid fractions were examined. The generation of aliphatic carboxylic acids as oxidation products was also investigated. The catalytically assisted oxidation was more efficient than the alkaline counterpart in dissolution of wood components under a four-hour treatment period resulting in higher dissolution of hemicelluloses. A longer reaction time of 20 hours leveled out the differences between the oxidation processes. Comparison of different bases showed that similar solubilisation of dry matter was obtained with NaOH, KOH, and Na2CO3. Oxidation in Na2CO3 caused higher dissolution of glucomannan and greater acid production. The dissolution of hemicellulose and lignin, and their oxidation to acids was most efficient in the first 4 hours of oxidation.

AB - Alkaline oxidation (AlkOx) is an effective fractionation technique for lignocellulosic raw materials. The efficiency of the AlkOx treatment can further be enhanced by using a catalyst (CatOx). Both CatOx and AlkOx provide a fiber fraction containing readily hydrolysable carbohydrates that can be utilized in biotechnical processes and a liquid fraction containing solubilized lignin and reaction products from various biomass components. The effects of different fractionation conditions on yields and chemical composition of solubilized and insoluble fractions were investigated. Two temperatures and two reaction times were studied with and without a catalyst. The composition and content of carbohydrates in the fiber and liquid fractions were examined. The generation of aliphatic carboxylic acids as oxidation products was also investigated. The catalytically assisted oxidation was more efficient than the alkaline counterpart in dissolution of wood components under a four-hour treatment period resulting in higher dissolution of hemicelluloses. A longer reaction time of 20 hours leveled out the differences between the oxidation processes. Comparison of different bases showed that similar solubilisation of dry matter was obtained with NaOH, KOH, and Na2CO3. Oxidation in Na2CO3 caused higher dissolution of glucomannan and greater acid production. The dissolution of hemicellulose and lignin, and their oxidation to acids was most efficient in the first 4 hours of oxidation.

KW - Catalysis

KW - alkaline oxidation

KW - chromatography

KW - capillary electrophoresis

KW - spruce

KW - pretreatment

KW - fractionation

M3 - Article

VL - 7

SP - 756

EP - 776

JO - BioResources

JF - BioResources

SN - 1930-2126

IS - 1

ER -

Rovio S, Kallioinen A, Tamminen T, Hakola M, Leskelä M, Siika-aho M. Catalysed alkaline oxidation as a wood fractionation technique. BioResources. 2012;7(1):756-776.