ACID HYDROLYSIS OF PRETREATED PALM OIL LIGNOCELLULOSIC WASTES

Palm oil solid wastes consist of cellulose, hemicellulose and lignin. In this study, a single stage of acid hydrolysis process of palm oil empty fruit bunch (EFB) for production of fermentable sugar was carried out under moderate temperature (45°C) and ambient pressure. The effect of four different process variables such as solid size, HC1 concentration, solid percentage and temperature were investigated. In addition, the effect of pretreatment with 0.5-1 M NaOH solution in acid hydrolysis was also investigated. Smaller particles provided more surfaces for acid-solid contact and longer reaction time was necessary if the large solid particles were used. High acid concentration improved the reaction rate and sugar yield. Therefore, the sugar yield was found to be dependent on acid concentration and the employed temperature as well. For a reaction time of 40 minutes, 5 % EFB solid with 15, 20, 25 and 30 percent of HC1, EFB lignocellulose fibers conversion of 36, 60, 65 and 80 % were achieved, respectively. The sugar concentration in acid hydrolysis of the pretreated fibers with 0.5 M sodium hydroxide solution resulted in 35 % more sugar