TY - JOUR
T1 - Structural and physico-chemical characterization of industrial hemp hurd
T2 - Impacts of chemical pretreatments and mechanical refining
AU - Bokhari, Syed M.Q.
AU - Chi, Kai
AU - Catchmark, Jeffrey M.
N1 - Funding Information:
This work was supported by 9Fiber Inc. and the USDA National Institute of Food and Agriculture Federal Appropriations under Project PAES 4602, accession number 1009850 . The authors are thankful to Dr. Tom L. Richard, Anahita Bharadwaj, Katharine Hirl, and Materials Research Institute for their facility and staff support in the material characterization. The authors confirm that there is no known conflict of interest associated with this publication and there has been no significant financial support for this work that could have influenced its outcome.
Publisher Copyright:
© 2021 Elsevier B.V.
PY - 2021/11/1
Y1 - 2021/11/1
N2 - Effective utilization of agricultural and industrial wastes has attracted increasing attention due to the promotion of sustainability and circular economy in our society. In this study, we investigated an economical and environmentally friendly decortication method using metal oxide-assisted hydrogen peroxide oxidization to separate hemp bast and hurd from wasted industrial hemp (Cannabis sativa) stalk. With various chemical pretreatments and mechanical refining, the compositional, structural, and physico-chemical properties of the resulting hemp hurd were comprehensively characterized and analyzed. Chemical composition analysis revealed that decorticated hemp hurd contained 45.66 % cellulose, 24.57 % hemicellulose, and 21.67 % lignin as its major components. The harsher milling conditions led to significantly reduced particle size and destroyed the crystalline structure of hemp hurd bio-aggregates, as indicated by X-ray diffraction and dynamic light scattering results. Chemical pretreatments disintegrated the native cell wall structure, broke covalent or hydrogen-bonded linkages between cell wall components, digested cell wall components, and fractionated hemp hurd into lignocellulosic bio-aggregates with differentiated chemical compositions, morphology, crystalline structure, and thermal stability. Compared to single-step chemical pretreatment, sequential alkaline and bleaching pretreatments removed most of the non-cellulosic components (32.4 wt% reduction) and rendered the resulting hemp hurd fibers with high crystalline structure (70.4 %) and sufficient thermal stability (maximum degradation temperature ∼355 °C). The current study may highlight the importance of chemical pretreatments and particle size for the upscaling of wasted industrial hemp hurd for papermaking, biorefinery, or bioplastic composites industry.
AB - Effective utilization of agricultural and industrial wastes has attracted increasing attention due to the promotion of sustainability and circular economy in our society. In this study, we investigated an economical and environmentally friendly decortication method using metal oxide-assisted hydrogen peroxide oxidization to separate hemp bast and hurd from wasted industrial hemp (Cannabis sativa) stalk. With various chemical pretreatments and mechanical refining, the compositional, structural, and physico-chemical properties of the resulting hemp hurd were comprehensively characterized and analyzed. Chemical composition analysis revealed that decorticated hemp hurd contained 45.66 % cellulose, 24.57 % hemicellulose, and 21.67 % lignin as its major components. The harsher milling conditions led to significantly reduced particle size and destroyed the crystalline structure of hemp hurd bio-aggregates, as indicated by X-ray diffraction and dynamic light scattering results. Chemical pretreatments disintegrated the native cell wall structure, broke covalent or hydrogen-bonded linkages between cell wall components, digested cell wall components, and fractionated hemp hurd into lignocellulosic bio-aggregates with differentiated chemical compositions, morphology, crystalline structure, and thermal stability. Compared to single-step chemical pretreatment, sequential alkaline and bleaching pretreatments removed most of the non-cellulosic components (32.4 wt% reduction) and rendered the resulting hemp hurd fibers with high crystalline structure (70.4 %) and sufficient thermal stability (maximum degradation temperature ∼355 °C). The current study may highlight the importance of chemical pretreatments and particle size for the upscaling of wasted industrial hemp hurd for papermaking, biorefinery, or bioplastic composites industry.
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U2 - 10.1016/j.indcrop.2021.113818
DO - 10.1016/j.indcrop.2021.113818
M3 - Article
AN - SCOPUS:85112486447
VL - 171
JO - Industrial Crops and Products
JF - Industrial Crops and Products
SN - 0926-6690
M1 - 113818
ER -
