|
|
Publicação
|
Título:
|
Chemical characterization of lignocellulosic materials by analytical pyrolysis
|
|
Tipo:
|
Capítulo de um Livro
|
|
Autor(es):
|
Ana Carina dos Santos Lourenço
,
Jorge Manuel Barros D Almeida Gominho
,
Helena Margarida Nunes Pereira
|
|
Resumo:
|
Analytical pyrolysis is used to chemically study complex molecular materials and is applied in a wide range of fields. Pyrolysis is a thermochemical process associated to the breaking of chemical bonds using thermal energy, transforming
a nonvolatile compound into a volatile degradation mixture. This chapter refers to analytical pyrolysis, i.e., when pyrolysis is used for chemical characterization, applied to samples with small particle sizes, at 500–650°C, and with short residence
times. The reactions that occur during pyrolysis of the structural components are discussed regarding the mechanisms and the pyrolysis products obtained from cellulose, hemicelluloses, and lignin. A compilation of data is made on the characterization
of lignocellulosic materials using Py-GC/FID(MS) or Py-GC/MS as analytical tools including woods and barks of several species. The pyrogram profiles and important parameters on lignin chemical composition such as the H:G:S relation
and the S/G ratio are summarized. Analytical pyrolysis is a versatile methodology that may be applied to characterize the lignin directly on the lignocellulosic material or after isolation from the cell wall matrix (e.g., as MWL or dioxane lignin)
or from pulps or spent liquors. It is therefore an excellent tool to study lignin compositional variability in different materials and along various processing pathways.
|
|
Palavras-chave:
|
Py-GC/MS, wood, barks, lignin, cellulose, H:G:S relation, S/G ratio
|
|
Livro referenciado:
|
Analytical Pyrolysis
|
|
Editora:
|
InTechOpen
|
|
Ano:
|
2019
|
Documentos
Não existem documentos.
|