Morphology of lignin structures on fiber surfaces after organosolv pretreatment

• The redeposition of lignin to the fiber surface after organosolv pretreatment was studied using two different reactor types. Results from the conventional autoclave reactor suggest that redeposition occurs during the cooling down stage. Redeposited particles appeared to be spherical in shape. The size and population density of the particles depends on the concentration of organosolv lignin in the cooking liquor, which is consistent with the hypothesis that reprecipitation of lignin occurs when the system is cooled down. The use of a displacement reactor showed that displacing the spent cooking liquor with fresh cooking liquor helps in reducing the redeposition and the inclusion of a washing stage with fresh cooking liquor reduced the reprecipitation of lignin, particularly on the outer fiber surfaces. Redeposition of lignin was still observed on regions that were less accessible to washing liquid, such as fiber lumens, suggesting that complete prevention of redeposition was not achieved. © 2022 The Authors. 

Subject headings

TEKNIK OCH TEKNOLOGIER  -- Maskinteknik -- Produktionsteknik, arbetsvetenskap och ergonomi (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Mechanical Engineering -- Production Engineering, Human Work Science and Ergonomics (hsv//eng)

Keyword

lignin morphology

lignin redeposition

organosolv pretreatment

SEM analysis of fiber surface

Fibers

Lignin

Particle size analysis

Population statistics

Surface morphology

Washing

Cooking liquor

Fibre surfaces

Lignin structure

Re-precipitation

Redeposition

SEM analyse of fiber surface

SEM analysis

Morphology

Publication and Content Type

ref (subject category)

art (subject category)