Resumo

NINO LOPEZ, Lilibeth; ACOSTA CARDENAS, Alejandro  e  GELVES ZAMBRANO, Ricardo. Evaluation of chemical pretreatments for enzymatic hydrolysis of lignocellulosic residues cassava (Manihot esculenta Crantz). Rev.fac.ing.univ. Antioquia [online]. 2013, n.69, pp.317-326. ISSN 0120-6230.

The effect of different chemical pretreatment with sulfuric acid (H₂SO₄), sodium hydroxide (NaOH) and hydrogen peroxide (H₂O₂) were evaluated by quantifying total reducing sugars produced during enzymatic hydrolysis step of lignocellulosic residues cassava (Manihot esculenta Crantz) and lignin removal percentage after pretreatment. The amount of waste used (1 to 5%) (w/v) in different particle sizes (1.18 and 0.6 mm) were pretreated separately (leaves and stems) with H₂SO₄, NaOH and H₂O₂ at varying concentrations (1 and 5%) (w/v). Plant residues were hydrolyzed with enzyme Accellerase 1500 with 50 ° C, pH 5 and 140 rpm. NaOH pretreatment enables higher total reducing sugars released during enzymatic hydrolysis (3.7 g/L) followed by leave pretreatments using H₂SO₄ (2.11 g/L) and H₂O₂ (1.54 g/L). Sugar concentrations were lower in stem pretreatments.

Palavras-chave : Pretreatment; hydrolysis; ethanol; lignocellulosic waste; cellulose; hemicellulose; lignin.