Xylooligosaccharides production by acid hydrolysis of an alkaline extraction filtrate from Eucalyptus globulus bleached kraft pulp

Abstract The finding that hexenuronic acid (HexA) groups can be selectively removed from kraft pulps by acid hydrolysis has provided an opportunity to reduce bleaching chemicals. However, there is evidence that the acid hydrolysis is not uniform. In this report, we evaluate the kinetics of acid hydrolysis of HexA in a xylan sample enriched with HexA, a conventional kraft pulp, and three modified kraft pulps: anthraquinone pulp (Kraft-AQ), polysulfide pulp (PS), and polysulfide-anthraquinone pulp (PS-AQ). We found that HexA present in the xylan and conventional kraft pulp behaved similarly toward the acid hydrolysis throughout. On the other hand, HexA present in the Kraft-AQ, PS-AQ and PS pulps was heterogeneous toward acid hydrolysis and the reaction can be separated into two pseudo-first-order kinetic phases, each of which has a different rate constant. The kinetic data provide evidence for the formation of lignin-HexA-xylan complexes during modified kraft pulping processes.

Download Full-text

Optimization of furfural production by acid hydrolysis of Eucalyptus globulus in two stages

Chemical Engineering Journal ◽

10.1016/j.cej.2013.11.073 ◽

2014 ◽

Vol 240 ◽

pp. 195-201 ◽

Cited By ~ 33

Author(s):

F. López ◽

M.T. García ◽

M.J. Feria ◽

J.C. García ◽

C.M. de Diego ◽

...

Keyword(s):

Acid Hydrolysis ◽

Eucalyptus Globulus ◽

Two Stages ◽

Hydrolysis Of ◽

Furfural Production

Download Full-text

Eucalyptus globulus Kraft Pulp Residual Lignins. Part 1. Effects of Extraction Methods upon Lignin Structure

Holzforschung ◽

10.1515/hf.2000.063 ◽

2000 ◽

Vol 54 (4) ◽

pp. 365-372 ◽

Cited By ~ 16

Author(s):

Ana Paula Duarte ◽

Danielle Robert ◽

Dominique Lachenal

Keyword(s):

Enzymatic Hydrolysis ◽

Acid Hydrolysis ◽

Eucalyptus Globulus ◽

Kraft Pulp ◽

Extraction Methods ◽

Extraction Yield ◽

Residual Lignin ◽

Softwood Kraft Pulp ◽

Ft Ir ◽

Hydrolysis Conditions

Summary Residual lignins of Eucalyptus globulus kraft pulp were shown to be structurally different depending upon the type of extraction chosen. Enzymatic hydrolysis releases a residual lignin with a well preserved etherified structure but substantially contaminated by protein and carbohydrate moieties coming from the enzyme. Moreover, the extraction yield is poor and obviously it does not work as well as in the case of softwood kraft pulp. The residual lignin extracted by acid hydrolysis has less etherified units and more free phenolic functions than that of the enzymatic hydrolysis. It contains some unsaturated structures but no carbohydrate contaminants. Comparison with Milled Wood Lignin (MWL) treated under the acid hydrolysis conditions shows that ether splitting occurs during this extraction. The different residual lignin fractions were characterised by HPSEC, FT-IR, 13C NMR and sugar analysis.

Download Full-text

Alkaline xylan extraction of bleached kraft pulp - effect of extraction time on pulp chemical composition and physical properties

TAPPI Journal ◽

10.32964/tj11.4.37 ◽

2012 ◽

Vol 11 (4) ◽

pp. 37-43 ◽

Cited By ~ 5

Author(s):

ESA SAUKKONEN ◽

KATJA LYYTIKÄINEN ◽

KAJ BACKFOLK

Keyword(s):

Kraft Pulp ◽

Pilot Trial ◽

Mechanical Damage ◽

Pilot Scale ◽

Extraction Time ◽

Similar Amount ◽

Alkaline Extraction ◽

Paper Properties ◽

Bleached Kraft Pulp ◽

Birch Kraft Pulp

In this pilot scale study, we examined the effects of alkaline extraction time on xylan removal, pulp and paper properties, and the consequences that need to be addressed when scaling up and intensifying the process. Alkaline extraction of bleached birch kraft pulp yields two fractions: pure polymeric xylan and pulp with reduced xylan content. Our results indicate that a similar amount of xylan can be extracted in 5 min as the amount obtained in 60 min. We found, however, that the shorter extraction time is beneficial to maintain the fiber and paper properties at an acceptable level. This pilot trial demonstrated that the washing procedure of the alkali-treated fibers must be selected with care to avoid causing mechanical damage to fibers and to avoid the loss of fines.

Download Full-text

Polysaccharides of tropical pasture herbage. II. A xylan from the leaf of spear grass (Heteropogon contortus)

Australian Journal of Chemistry ◽

10.1071/ch9702361 ◽

1970 ◽

Vol 23 (11) ◽

pp. 2361 ◽

Cited By ~ 16

Author(s):

JD Blake ◽

GN Richards

Keyword(s):

Gas Chromatography ◽

Acid Hydrolysis ◽

Copper Complex ◽

Glucuronic Acid ◽

Single Units ◽

Alkaline Extraction ◽

Tropical Pasture ◽

Fractional Precipitation ◽

Heteropogon Contortus ◽

Hydrolysis Of

Alkaline extraction of spear grass holocellulose gave a xylan which was purified by fractional precipitation as a copper complex. Acid hydrolysis yielded L-arabinose, D-xylose, and an aldobiouronic acid consisting of D-xylose and 4-O-methyl-D-glucuronic acid. Hydrolysis of the methylated xylan gave 2,3,5-tri-O-methyl-L- arabinose, 2,3,4-tri-, 2,3-di-, and 2-O-methyl-D-xylose, and 3-O-methyl-2-O-(2,3,4-tri-O-methyl-D-glucopyranosyluronic acid)-D-xylose. The conditions for isolation of the methylated sugars for gas chromatography were investigated with particular reference to difficulties arising from volatility of the tri-O-methyl pentoses. The xylan is composed of chains of 1,4-linked �-D-xylopyranose residues to which are attached single units of L-arabinofuranose at position 3 and 4-O-methyl-D-glucuronic acid at position 2 of the basal residues.

Download Full-text

Microwave Assisted-Acid Hydrolysis of Jabon Kraft Pulp

Waste and Biomass Valorization ◽

10.1007/s12649-017-0182-9 ◽

2018 ◽

Vol 10 (6) ◽

pp. 1503-1517 ◽

Cited By ~ 5

Author(s):

Widya Fatriasari ◽

Triyani Fajriutami ◽

R. P. Budi Laksana ◽

Nyoman J. Wistara

Keyword(s):

Acid Hydrolysis ◽

Kraft Pulp ◽

Microwave Assisted ◽

Hydrolysis Of

Download Full-text

Tailorable cellulose II nanocrystals (CNC II) prepared in mildly acidic lithium bromide trihydrate (MALBTH)

Green Chemistry ◽

10.1039/d1gc00145k ◽

2021 ◽

Vol 23 (7) ◽

pp. 2778-2791

Author(s):

Ning Li ◽

Huiyang Bian ◽

J. Y. Zhu ◽

Peter N. Ciesielski ◽

Xuejun Pan

Keyword(s):

Kraft Pulp ◽

Lithium Bromide ◽

Ammonium Persulfate ◽

Cellulose Ii ◽

Persulfate Oxidation ◽

Bleached Kraft Pulp ◽

Hydrolysis Of ◽

Polymorph Transformation

Cellulose II nanocrystals were prepared from bleached kraft pulp via simultaneous hydrolysis of disordered cellulose and polymorph transformation in mildly acidic lithium bromide trihydrate followed by ammonium persulfate oxidation.

Download Full-text