TY - JOUR
T1 - Optimization of ultrasound pretreatment and enzymatic hydrolysis of wheat straw
T2 - From lab to semi-industrial scale
AU - Gaudino, Emanuela Calcio
AU - Grillo, Giorgio
AU - Tabasso, Silvia
AU - Stevanato, Livio
AU - Cravotto, Giancarlo
AU - Marjamaa, Kaisa
AU - Pihlajaniemi, Ville
AU - Koivula, Anu
AU - Aro, Nina
AU - Uusitalo, Jaana
AU - Ropponen, Jarmo
AU - Kuutti, Lauri
AU - Kivinen, Pauliina
AU - Kanerva, Heimo
AU - Arshanitsa, Alexander
AU - Jashina, Lilija
AU - Jurkjane, Vilhelmine
AU - Andersone, Anna
AU - Dreyer, Thomas
AU - Schories, Gerhard
N1 - Funding Information:
Dedication in memory of Prof. Dr. Galina Telysheva, an appreciated research leader, with the highest esteem of all the scientific community. This work was supported by the BBI-JU Project US4GREENCHEM (Grant Agreement n° 669055 ) “Combined Ultrasonic and Enzyme Treatment of Lignocellulosic Feedstock as Substrate for Sugar Based Biotechnological Applications”. Authors thank Riitta Alander, Mariitta Svanberg, Kirsi Kiiveri, Riitta Isoniemi, Sirpa Holm, Juha Kannelkoski and Jari Leino (VTT) for excellent technical assistance.
Publisher Copyright:
© 2022 Elsevier Ltd
PY - 2022/12/20
Y1 - 2022/12/20
N2 - In this paper, the dominance of the physical effects of ultrasound (US) pretreatment in improving the delignification of wheat straw at a 1:20 solid/liquid (biomass/water) ratio is reported showing low-frequency/high power (25 kHz, 2 or 3 kW) as preferred conditions. The sonochemical pretreatment with alkali was identified as an optimal method to make the cellulose more susceptible to further enzymatic hydrolysis, thereby increasing the yield of soluble sugars. Previous bench-scale studies have shown that US pretreatment has a positive effect on delignification, nevertheless this has not yet been demonstrated on a larger scale. The objective of this study was to demonstrate the effectiveness of US pretreatment for wheat straw delignification from lab to semi-industrial scale (40 kg biomass) in terms of sugar yield and energy efficiency. A 59.2% of lignin removal was recorded after the cavitational treatment of wheat straw with a subsequent 68 ± 5.7% yield in terms of enzymatic hydrolysis (52.6% glucose, 42.9% xylose and 4.5% arabinose). It was demonstrated that the positive effect of US alkali pretreatment of wheat straw on sugar yield was due to a combination of factors, including (i) an easier accessibility of the biomass carbohydrate network to enzymes due to the increased wheat straw porosity, (ii) the partial removal of lignin, which increases the relative proportion of carbohydrates in the treated biomass, and (iii) the disordering (amorphization) of the cellulose structure, which promotes carbohydrate hydrolysis as well as saponification of the acetyl groups in the hemicellulose. With respect to the Life Cycle Assessment (LCA) and the Cost Benefit Analysis the US pretreatment process herein reported was compared to an alternative Steam Explosion pretreatment. The results of the LCA analysis showed, that for all five environmental categories (energy consumption, global warming potential, water and fossil depletion, and the land occupation) the US pretreatment has advantages in comparison with the standard industrial Steam Explosion pretreatment.
AB - In this paper, the dominance of the physical effects of ultrasound (US) pretreatment in improving the delignification of wheat straw at a 1:20 solid/liquid (biomass/water) ratio is reported showing low-frequency/high power (25 kHz, 2 or 3 kW) as preferred conditions. The sonochemical pretreatment with alkali was identified as an optimal method to make the cellulose more susceptible to further enzymatic hydrolysis, thereby increasing the yield of soluble sugars. Previous bench-scale studies have shown that US pretreatment has a positive effect on delignification, nevertheless this has not yet been demonstrated on a larger scale. The objective of this study was to demonstrate the effectiveness of US pretreatment for wheat straw delignification from lab to semi-industrial scale (40 kg biomass) in terms of sugar yield and energy efficiency. A 59.2% of lignin removal was recorded after the cavitational treatment of wheat straw with a subsequent 68 ± 5.7% yield in terms of enzymatic hydrolysis (52.6% glucose, 42.9% xylose and 4.5% arabinose). It was demonstrated that the positive effect of US alkali pretreatment of wheat straw on sugar yield was due to a combination of factors, including (i) an easier accessibility of the biomass carbohydrate network to enzymes due to the increased wheat straw porosity, (ii) the partial removal of lignin, which increases the relative proportion of carbohydrates in the treated biomass, and (iii) the disordering (amorphization) of the cellulose structure, which promotes carbohydrate hydrolysis as well as saponification of the acetyl groups in the hemicellulose. With respect to the Life Cycle Assessment (LCA) and the Cost Benefit Analysis the US pretreatment process herein reported was compared to an alternative Steam Explosion pretreatment. The results of the LCA analysis showed, that for all five environmental categories (energy consumption, global warming potential, water and fossil depletion, and the land occupation) the US pretreatment has advantages in comparison with the standard industrial Steam Explosion pretreatment.
KW - Delignification
KW - Enzymatic hydrolysis
KW - Life cycle assessment
KW - Semi-industrial scale
KW - Ultrasound pretreatment
KW - Wheat straw
UR - http://www.scopus.com/inward/record.url?scp=85141495036&partnerID=8YFLogxK
U2 - 10.1016/j.jclepro.2022.134897
DO - 10.1016/j.jclepro.2022.134897
M3 - Article
AN - SCOPUS:85141495036
SN - 0959-6526
VL - 380
JO - Journal of Cleaner Production
JF - Journal of Cleaner Production
IS - Part 1
M1 - 134897
ER -
