Cellulose and hemicellulose recovery from oil palm empty fruit bunch (EFB) fibers and production of sugars from the fibers

A sequential two-step treatment with peracetic acid (PA) and alkaline peroxide (AP) at mild temperatures (20-35 °C) removed more than 98% of the lignin from oil palm empty fruit bunch (EFB) fiber. For each kilogram of EFB fiber treated, 200-250 g of a solids fraction and 120-170 g of a precipitate fraction were recovered after the treatment. Subsequent enzymatic hydrolysis (45 °C, 72 h) of the recovered solids (excluding the precipitate) resulted in a glucose yield of 629.8 ± 0.5 g per kg of the original dry EFB biomass. Enzymatic hydrolysis of untreated EFB yielded only 3.0 ± 0.0 g glucose per kg of dry EFB. Therefore, the PA-AP pretreatment enhanced glucose recovery from EFB by nearly 210-fold. The total treatment time was 93 h (a 9 h PA treatment at 35 °C, a 12 h treatment with AP (20 °C, 4% NaOH), 72 h of enzymatic hydrolysis).