Lignin Valorization for Added-Value Chemicals: Kraft Lignin versus Lignin Fractions

• Tipo: Artigo em Revista Científica Internacional
• Data: 2023

Autores

Carina Costa (Autor) FEUP; Casimiro, FM (Autor) Outra; Vega-Aguilar, C (Autor) Outra; Rodrigues, AE (Autor) Outra

Revista

A Revista está pendente de validação pelos Serviços Administrativos.

Título: CHEMENGINEERING

Vol. 7

Página Final: 42

ISSN: 2305-7084

Indexação

ISI Web of Knowledge - 0 Citações

Scopus - 0 Citações

Projetos Associados

LA LSRE-LCM - Financiamento Plurianual 2020-2023 para a Unidade LA LSRE-LCM Laboratório de Processos de Separação e Reacção - Laboratório de Catálise e Materiais

Outras Informações

ID Authenticus: P-00Y-P8M

DOI: 10.3390/chemengineering7030042

Abstract (EN): Lignin is a raw material that can potentially be converted into valuable compounds through depolymerization reactions in addition to its use as a polymer or material. However, the chemical recalcitrance and the heterogeneous composition and structure of lignin make it challenging to establish processes that add value to this complex aromatic biopolymer. In this work, solvent fractionation was applied to obtain lignin fractions with a narrowed molecular weight and specific structural characteristics, improving its homogeneity and purity. A kraft lignin was submitted to fractionation using different ratios of acetone, ranging from 60 to 15% v/v, in aqueous mixtures. The composition, structure, and molecular weight of each fraction were studied and their potential applications were evaluated. The most water-soluble fraction has more phenolic OH, less aliphatic OH groups, and shows the lowest content of aryl-ether linkages, which is in accordance with its highest degree of condensation. On the other hand, the insoluble fraction from the mixture with 60% of acetone has the lowest molecular weight and the highest content of inorganic material. Radar plots were applied for lignin fractions evaluation and the fraction with the highest potential (IF 30:70) was submitted to alkaline oxidation with O-2. The results were compared with the products yielded from kraft lignin. An increase of about 13 and 19% was found for vanillin and syringaldehyde, respectively, when the fraction IF 30:70 was submitted to oxidation. In conclusion, the proposed fractionation process showed to be an effective method to obtain lignin fractions with specific composition and structural characteristics that could improve its potential as a source of high added-value monomeric phenolic compounds.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 16