title: Effects of autohydrolysis of Eucalyptus urograndis and Eucalyptus grandis on influence of chemical components and crystallinity index.
abstract: Samples of Eucalyptus urograndis and Eucalyptus grandis sawdust were autohydrolyzed in aqueous conditions to reach temperatures in the range 110-190°C and reaction times of 0-150min in a minireactor. In each minireactor were used a liquor:wood ratio (10:1 L:kg dry wood), in order to assess the effects of the autohydrolysis severity and the crystalline properties of cellulose. The content of extractives, lignin, holocellulose, cellulose, hemicelluloses and crystallinity index obtained from the solid fraction after autohydrolysis of sawdust were determined. This study demonstrated that the hemicelluloses were extensively removed at 170 and 190°C, whereas cellulose was partly degraded to Eucalyptus urograndis and Eucalyptus grandis sawdust. The lignin content decreased, while the extractives content increased. It was defined that during autohydrolysis, had a slight decreased on crystalline structure of cellulose of Eucalyptus urogandis and Eucalyptus grandis.
authors.affiliation: Laboratório de Celulose e Papel, Departamento de Ciência Florestal, Faculdade de Ciências Agronômicas/UNESP, Faz Experimental Lageado, José Barbosa de Barros, 1780, CEP: 18610-307 Botucatu, SP, Brazil. Electronic address: alainepatriciamorais@yahoo.com.br.
authors.forename: Alaine Patrícia
authors.initials: AP
authors.lastname: da Silva Morais
authors.affiliation: Laboratório de Celulose e Papel, Departamento de Ciência Florestal, Faculdade de Ciências Agronômicas/UNESP, Faz Experimental Lageado, José Barbosa de Barros, 1780, CEP: 18610-307 Botucatu, SP, Brazil. Electronic address: sansigolo@fca.unesp.br.
authors.forename: Cláudio Angeli
authors.initials: CA
authors.lastname: Sansígolo
authors.affiliation: Departamento de Física e Biofísica, Instituto de Biociências/UNESP, Distrito de Rubião Júnior, S/N, CEP: 18618-970 Botucatu, SP, Brazil. Electronic address: mario.neto@ibb.unesp.br.
authors.forename: Mario
authors.initials: M
authors.lastname: de Oliveira Neto
mesh_terms: D019149:Bioreactors; D001938:Brazil; D002482:Cellulose / Q000737:chemistry*; D005052:Eucalyptus / Q000737:chemistry*; D006358:Hot Temperature; D006868:Hydrolysis; D008031:Lignin / Q000737:chemistry; D014867:Water / Q000032:analysis; D014934:Wood / Q000737:chemistry
chemical_list: D014867:Water; D002482:Cellulose; D008031:Lignin
keywords: Autohydrolysis; Chemical components; Crystallinity; Eucalyptus grandis; Eucalyptus urograndis