The effectiveness of alkaline and thermo hydrolysis pretreatments in the bioethanol production from Calliandra calothyrsus wood

Abstract

The demand in energy is increasing along with the development of technology. However, the utilization of fossil energy as the main current energy sources creates various environmental problems. Hence, it is important to search other energy sources which are environmentally friendly. One of the renewable energy sources is bioethanol produced from woody biomass. The purpose of this study was to investigate the suitability of Calliandra calothyrsus wood under development of alkaline and thermohydrolisis pretreatments. These pretreatments included the variations of 15, 30, 45 and 60 min at 121°C with NaOH concentration of 1, 2, and 3% (w/v). The chemical component analysis was conducted by using the TAPPI method, while the percentage of reducing sugar after saccharification was carried out by the Nelson-Somogy method. The results showed that the highest holocellulose content 60,62%, and the highest α-cellulose content was 64,30%. The highest pulp saccharification test results were obtained from 60 min pretreatment of 3% concentration of NaOH, which was 42,82% and 32,99% wood basis. The highest yield of ethanol potential was obtained from 36 hours saccharification, which was 139 L/Ton. Finally, it is suggested to do additional treatments with variations in concentration and temperature in order to obtain more optimal results.