Ethanol Production from Oil Palm Trunk: A Combined Strategy Using an Effective Pretreatment and Simultaneous Saccharification and Cofermentation

Background. Oil palm trunk (OPT) with highly cellulose content is a valuable bioresource for bioethanol production. To produce ethanol from biomass, pretreatment is an essential step in the conversion of lignocellulosic biomass to fermentable sugars such as glucose and xylose. Several pretreatment methods have been developed to overcome biomass recalcitrance. In this study, the effects of different pretreatment methods such as alkali pretreatment, microwave-alkali, and alkaline peroxide combined with autoclave on the lignocellulosic biomass structure were investigated. Moreover, ethanol production from the treated biomass was performed by simultaneous saccharification and cofermentation (SSCF) under different temperatures, fermentation times, and cell ratios of Saccharomyces cerevisiae NCYC 479 and pentose-utilizing yeast, Pichia stipitis NCYC 1541. Results. Pretreatment resulted in a significant lignin removal up to 83.26% and cellulose released up to 80.74% in treated OPT by alkaline peroxide combined with autoclave method. Enzymatic hydrolysis of treated OPT resulted in an increase in fermentable sugar up to 93.22%. Optimization of SSCF by response surface method showed that the coculture could work together to produce maximum ethanol (1.89%) and fermentation efficiency (66.14%) under the optimized condition. Conclusion. Pretreatment by alkaline peroxide combined with autoclave method and SSCF process could be expected as a promising system for ethanol production from oil palm trunk and various lignocellulosic biomass.

Chemical Composition of Parenchyma and Vascular Bundle from Elaeis guineensis

Elaeis guineensis is an alternative source of raw materials for renewable energy in Malaysia. Thus, to enhance the use of the abundant biomass generated by the oil palm industry in Malaysia, a study was conducted in view of exploring the chemical composition such as sugar potential of this industrial byproduct. In this context, oil palm trunks were separated into individual cell that are parenchyma and vascular bundle to investigate the fundamental research about oil palm trunk. The aim of this study was to examine the chemical composition of parenchyma and vascular bundle of oil palm trunk. The oil palm trunk was kept under shade at room temperature of 28–30°C for 0, 45, and 60 days. The chemical composition analysis was carried out according to TAPPI methods. Based on storage time and different part of oil palm trunk, the result has shown that the sugar content was higher in parenchyma compared to vascular bundle and increase at the storage time of 0, 45, and 60 days while amount of starch showed decrease at the same storage time. It shows that conversion or fermentation of starch to sugar occur in oil palm trunk during storage times of 0, 45, and 60 days, respectively.

Biopellet from demineralized oil palm trunk

Oil palm trunk (OPT) is a potential raw material for biopellet manufacturing. This study aimed to reduce the ash content of biopellet through pre-treatment with sulfuric acid. The moisture content, durability, ash content, density, and calorific values of the biopellet were determined according to DIN EN 14961-2 and 51731 standards. Scanning electron microscopy (SEM) indicated the presence of inter-particle interlocking in the highly durable biopellet. Thermal analysis indicated that the mass and water loss, hemicellulose, cellulose, and lignin decomposition occurred at 76.12 ºC, 113.97-200 ºC, 310-360 ºC, and >400 ºC, respectively. Biopellet produced retained a moisture content of 3.40-8.90%, the durability of 97.75-99.38%, ash content after pre-treatment with H2SO4 of 1.02-1.47%, control ash content of 2.20-3.31%, the density of 1.03-1.30 g/cm3, and the calorific value of 3954-4608 kcal/kg. The biopellet quality fulfilled the requirements of DIN EN 14961-2, 51731, and SNI 8021-2014 standard, except for the ash content of the control.

The effect of oil palm trunk particles and composite density on the physical and mechanical properties of rigid polyurethane foam composite

The oil palm trunk (OPT) particle was used as a filler for the manufacture of rigid polyurethane foam composites (RPUFC). The purpose of this research is to investigate the effect of OPT particle content and variation of composite density on the physical and mechanical properties of RPUFC. The RPUFC was created with five different volume fractions of OPT particles (0, 2.5, 5, 7.5, 10 wt%) and three different composite densities (40, 50, 60 kg/m3). The OPT particles, polyols, and isocyanate were mixed, poured and formed in a closed mold. The moisture content (MC), water absorption (WA), compressive strength (CS), screw withdrawal (SW), and internal bonding strength (IB) properties were determined according to JIS A 5908-2003. The flexural strength (FS) properties were determined according to ASTM D790. The physical properties (MC, WA) were increased with increasing OPT particles in the RPUFC. The RPUFC with 2.5% OPT particle was higher in modulus of rupture, modulus of young and CS values compared to RPUFC control. The IB and SW values were increased when 2.5% OPT particles were added to RPUFC. The best PURFCs were produced with the addition of 2.5% particles at a density of 50 and 60 kg/m3.