Lignin contributions to the nanoscale porosity of raw and treated lignocelluloses as observed by calorimetric thermoporometry

Author(s)

Driemeier, Carlos ^[1] ; Oliveira, Marcelo M. ^{[1, 2]} ; Curvelo, Antonio A. S. ^{[1, 3]}

Affiliation

^[1] CNPEM, Lab Nacl Ciencia & Tecnol Bioetanol CTBE, Caixa Postal 6192, BR-13083970 Sao Paulo - Brazil

^[2] Univ Sao Paulo, EESC, Caixa Postal 780, BR-13560970 Sao Paulo - Brazil

^[3] Univ Sao Paulo, IQSC, Caixa Postal 780, BR-13560970 Sao Paulo - Brazil

• Document type: Journal article
• Source: INDUSTRIAL CROPS AND PRODUCTS; v. 82, p. 114-117, APR 2016.
• Web of Science Citations: 9

Abstract

Thermoporometry probes water in nanoscale confinement, the so-called freezing bound water (FBW). Although well established for characterization of delignified cellulosics, application and interpretation of thermoporometry has been elusive for lignin-containing biomass. Here we show that calorimetric thermoporometry discriminates two types of lignin contributions to the nanoscale porosity of a wide set of raw and treated lignocelluloses. First, the well-known role of lignin as pore filler is observed as delignification-promoted gains in FBW, mainly in pores of 10-200 nm. Second, lignocelluloses submitted to acidic aqueous treatments present an additional FBW contribution, mainly in pores <4 nm. This FBW at smaller dimensions is attributed to surface irregularities of the lignin aggregates left by the acidic treatments. Hence, our findings demonstrate that thermoporometry detects a confined water state associated with restructured lignin, thus contributing to the understanding of processes for biomass valorization. (C) 2015 Elsevier B.V. All rights reserved. (AU)

• FAPESP's process: 10/05523-3 - Nanomorphologic changes of sugarcane lignocellulosic matter
• Grantee: Carlos Eduardo Driemeier
• Support Opportunities: Research Grants - Young Investigators Grants