Review Article: Appropriate Hydrothermal Pretreatment of Oil Palm Biomass in Palm Oil Mill

Oil palm (Elaeis guineensis Jacq.) is one of the most planted trees in Malaysia for the palm oil production.  Thus, solid biomass had been generated from this industry such as empty fruit bunch, shell, mesocarp fibre, frond and trunk produced that causes problematic to the nation and expected to escalate up to 85-110 million tonnes by 2020. Besides that, palm oil mill effluent and excessive steam also generated from the production of palm oil. In situ hydrothermal pretreatment means the utilisation of excessive steam produced by the oil palm mill and at the same time, generating value added product as well as reducing the biomass. Oil palm biomass is rich in lignocellulosic materials which comprised of lignin, hemicellulose and cellulose. Refinement of lignocellulosic from oil palm biomass can be utilised to form fermentable sugar, bioethanol and other potential chemicals. Recalcitrant property of lignocellulosic reduces the ability of enzymes to penetrate, thus pretreatment is required prior to hydrolysis process. Pretreatment can be either physical, chemical, biological or combined. In this review paper, three types of hydrothermal pretreatment were discussed as suitable in situ pretreatment process for oil palm biomass; in palm oil mill. The suitability was measured based on the availability of excess steam and energy in the mill. Furthermore, physicochemical pretreatment also facilitate the saccharification process, whereby it loosened the lignocellulose structure and increase the surface area. The effects and factors in choosing right pretreatment are highlighted in this paper

Appropriate hydrothermal pretreatment of oil palm biomass in palm oil mill

Oil palm (Elaeis guineensis Jacq.) is one of the most planted trees in Malaysia for the palm oil production. Thus, solid biomass had been generated from this industry such as empty fruit bunch, shell, mesocarp fibre, frond and trunk produced that causes problematic to the nation and expected to escalate up to 85-110 million tonnes by 2020. Besides that, palm oil mill effluent and excessive steam also generated from the production of palm oil. In situ hydrothermal pretreatment means the utilisation of excessive steam produced by the oil palm mill and at the same time, generating value added product as well as reducing the biomass. Oil palm biomass is rich in lignocellulosic materials which comprised of lignin, hemicellulose and cellulose. Refinement of lignocellulosic from oil palm biomass can be utilised to form fermentable sugar, bioethanol and other potential chemicals. Recalcitrant property of lignocellulosic reduces the ability of enzymes to penetrate, thus pretreatment is required prior to hydrolysis process. Pretreatment can be either physical, chemical, biological or combined. In this review paper, three types of hydrothermal pretreatment were discussed as suitable in situ pretreatment process for oil palm biomass; in palm oil mill. The suitability was measured based on the availability of excess steam and energy in the mill. Furthermore, physicochemical pretreatment also facilitate the saccharification process, whereby it loosened the lignocellulose structure and increase the surface area. The effects and factors in choosing right pretreatment are highlighted in this paper

Review article: appropriate hydrothermal pretreatment of oil palm biomassin palm oil mill

Oil palm (Elaeis guineensis Jacq.) is one of the most planted trees in Malaysia for the palm oil production. Thus, solid biomass had been generated from this industry such as empty fruit bunch, shell, mesocarp fibre, frond and trunk produced that causes problematic to the nation and expected to escalate up to 85-110 million tonnes by 2020. Besides that, palm oil mill effluent and excessive steam also generated from the production of palm oil. In situ hydrothermal pretreatment means the utilisation of excessive steam produced by the oil palm mill and at the same time, generating value added product as well as reducing the biomass. Oil palm biomass is rich in lignocellulosic materials which comprised of lignin, hemicellulose and cellulose. Refinement of lignocellulosic from oil palm biomass can be utilised to form fermentable sugar, bioethanol and other potential chemicals. Recalcitrant property lignocellulosic reduces the ability of enzymes to penetrate, thus pretreatment is required prior to hydrolysis process. Pretreatment can be either physical, chemical, biological or combined. In this review paper, three types of hydrothermal pretreatment were discussed as suitable in situ pretreatment process for oil palm biomass; in palm oil mill. The suitability was measured based on the availability of excess steam and energy in the mill. Furthermore, physicochemical pretreatment also facilitate the saccharification process, whereby it loosened the lignocellulose structure and increase the surface area. The effects and factors in choosing right pretreatment are highlighted in this paper

Hydrothermal pretreatment of mixed oil palm biomass

Oil palm biomass has high amount of carbohydrates which potentially to be converted into biosugar. Due to complex structure of the lignocellulosic component, pretreatment is needed to allow the penetration of cellulase into cellulose. While several pretreatments were available to open up the lignocellulosic structure, hydrothermal pretreatment process was chosen as the effectiveness and environmental-friendly process. Earlier research using individual biomass in different pretreatment processes had proven great effect on conversion of glucose. In this study, a pretreatment process was tested on mixed biomass to adapt bulk amount of biomass produced daily. The aim is to achieve high cellulose content after hydrothermal preatment. Mixing ratio of oil palm biomass was 1:1:1 of 2.0 mm size that involved empty fruit bunch, mesocarp fibre and frond fiber, and then continued to hydrothermal pretreatment with different severity factors (log, Rₒ) of 2.48 until 5.14. Chemical composition of untreated and pretreated mixed oil palm biomass was determined using acid hydrolysis. Each sample was examined with scanning electron microscope, wide-angle x-ray diffraction, and Brunauer-Emmett-Teller surface area analyses to check on the structure of biomass after pretreatment. High cellulose content which 50.1±0.3% was successfully achieved at temperature of 190˚C in 10 min. In conclusion, this experiment succeeded to approve that by hydrothermal pretreatment can give high cellulose content in mixed oil palm biomass under low temperature and short time

Production of glucose from mixed oil palm biomass using hydrothermal pretreatment

As the world second biggest palm oil producer, Malaysia has most of its agricultural land planted with oil palm (Elaeis guineensis Jacq.). In conjunction with that, various and bulky amount of oil palm biomass were produced from the plantations and mills which contained a high amount of lignocellulosic components. The conversion of oil palm biomass into a value added product such as glucose helps to reduce the abundance of oil palm biomass. However, the structure of the biomass is compact and tough to be broken down. Therefore, pretreatment process is required to open up the lignocellulosic structure for enzymatic reaction thus improving the production of glucose. Hydrothermal pretreatment process is an effective and environmental-friendly process for biomass fractionation due to its ability to solubilize hemicellulose; open the lignocellulosic structure and contributes to self-association of water molecules to create hydronium ions that can turn water pH into acidic, thus increasing the efficiency of pretreatment. Previous studies were using individual biomass in various pretreatment processes had shown a great effect on glucose conversion. In this study, hydrothermal pretreatment process was tested on mixed oil palm biomass to accommodate the huge amount of biomass produced daily. The aims of this experiment are to determine the effectiveness of hydrothermal pretreatment towards the lignocellulosic composition of mixed oil palm biomass and also to improve the glucose yield from pretreated mixed oil palm biomass using Acremonium cellulase. Different weight ratios of oil palm biomass mixture were treated, i.e. 1:1:1, 1:1:2, 1:2:1 and 2:1:1 of oil palm frond fiber: oil palm empty fruit bunch: oil palm mesocarp fiber (OPFF:OPEFB:OPMF), respectively. The individual and mixed biomass were then subjected to hydrothermal pretreatment with different severity factors (log R0) of 3.37 – 3.96 using miniclave reactor. The individual samples were represented as a control to investigate the effectiveness of mixed samples. The morphological structure was examined with scanning electron microscope, wide-angle x-ray diffraction, Fourier-transform infrared spectral analysis and Brunauer-Emmett-Teller surface area analyses to observe the structure of oil palm biomass before and after pretreatment. The compositional analysis results were obtained by following National Renewable Energy Laboratory (NREL) method using dilute acid hydrolysis. Enzymatic hydrolysis of untreated and treated individual and mixed oil palm biomass was performed using 10 FPU of Acremonium cellulase per g of biomass was studied. The enzymatic hydrolysis was conducted at 50˚C for 72 hours in shaking condition. Acremonium cellulase has endocellulase and β-glucosidase activities which converted cellulose into monosaccharides mainly glucose. In conclusion, the hydrothermal pretreatment had shown positive feedback towards high cellulose amount (53.8 ± 0.4%) of 1:2:1 mixed ratio under 190˚C for 10 min. The highest glucose yield also produced from the same mixed ratio under the same condition at 99.0 ± 0.8% under oil palm biomass ratio of 1:2:1 (OPFF:OPEFB:OPMF). Besides, the mixed sample also showed an increment of 22% of glucose conversion increment compared to the individual sample