Applicability assessment of empty fruit bunches from palm oil mills for use as bio-solid refuse fuels

Enhanced biofuel production from Sacha Inchi wastes: Optimizing pyrolysis for higher yield and improved fuel properties

Sacha inchi waste consists of residues (SR) and shells (SS) that are processed into liquid fuel using a traditional pyrolysis process. Pyrolysis was performed at a constant heating rate of 20 °C/min and nitrogen flow rate of 100 mL/min. Before the process took place, a preliminary TGA analysis was performed and the results revealed that the appropriate pyrolysis temperature and time allowed a variation of 250-450 °C and 10-50 min, respectively. The results showed that the pyrolysis oil yields of both SR and SS increased with increasing pyrolysis temperature and time. However, the pyrolysis oil yield of SR was significantly higher than that of SS because the main component of SR contains abundant carbon from saturated fatty acids. The ANOVA method shows that the SS model is more complex and examines more terms and interactions, whereas the SR model is simpler and focuses on fewer components, but still shows significant effects, especially through temperature. The nonsignificant p-value for time in the SR model suggests that time may not have the same influence as temperature on the dependent variable. The SS pyrolysis oil was consistent and resulted in a constant calorific value and flash point between 31.10 and 32.14 MJ/kg and 120 and 124 °C, respectively. However, decreasing the O/C atomic ratio of SR pyrolysis oil from 0.92 to 0.38 influenced the increasing calorific value from 36.66 to 38.75 MJ/kg, while the H/C atomic ratio of SR pyrolysis oil was close to 2.00. This suggests that its effectiveness maintains an alkene structure that can improve fuel efficiency. The molecular formulae of the SS pyrolysis oil were CH16N0.04O7 and that of SR pyrolysis oil was CH2.2N0.08O0.45.

Grouping of unused agricultural by-product biomass for fuel conversion in South Korea through multivariate analysis

While biomass holds significance as a resource, its abundance in South Korea is limited. Therefore, in this study analyzed the chemical characteristics of agricultural by-products produced and evaluated their fuel potentiality. To achieve this objective, multivariate analysis was utilized to create biomass clusters with diverse feature. All investigated biomass types showed heating values of at least 12.6 MJ/kg, adhering to South Korea's Bio-solid recovered fuel (SRF) standard, once the moisture content was reduced to 20 % or less. However, the biomasses only met the heating value of Level 3 of the European standard for SRF, which is at least 15 MJ/kg. Groups were formed based on a multivariate analysis using four variables: the high heating value, and carbon, nitrogen, and ash contents. The groups were centered around wood chips and hog fuel, with a cluster of lignocellulosic biomass materials surrounding them. The clusters formed around four groups. When the biomasses in each group were mixed, the combustion characteristics were compared to the ignition, maximum, and burn-out temperatures. Utilizing biomass grouping, by-products from agriculture and livestock in South Korea can be effectively employed as energy sources.

Palm oil industrial wastes as a promising feedstock for biohydrogen production: A comprehensive review

By the year 2050, it is estimated that the demand for palm oil is expected to reach an enormous amount of 240 Mt. With a huge demand in the future for palm oil, it is expected that oil palm by-products will rise with the increasing demand. This represents a golden opportunity for sustainable biohydrogen production using oil palm biomass and palm oil mill effluent (POME) as the renewable feedstock. Among the different biological methods for biohydrogen production, dark fermentation and photo-fermentation have been widely studied for their potential to produce biohydrogen by using various waste materials as feedstock, including POME and oil palm biomass. However, the complex structure of oil palm biomass and POME, such as the lignocellulosic composition, limits fermentable substrate available for conversion to biohydrogen. Therefore, proper pre-treatment and suitable process conditions are crucial for effective biohydrogen generation from these feedstocks. In this review, the characteristics of palm oil industrial waste, the process used for biohydrogen production using palm oil industrial waste, their pros and cons, and the influence of various factors have been discussed, as well as a comparison between studies in terms of types of reactors, pre-treatment strategies, the microbial culture used, and optimum operating condition have been presented. Through biological production, hydrogen production rates up to 52 L-H₂/L-medium/h and 6 L-H₂/L-medium/h for solid and liquid palm oil industrial waste, respectively, can be achieved. In short, the continuous supply of palm oil production by-product and relatively, the low cost of the biological method for hydrogen production indicates the potential source of renewable energy.

Bioethanol Production from Cassava Peel Treated with Sulfonated Carbon Catalyzed Hydrolysis

A large amount of Cassava peel as biomass waste is generated by agricultural activities, and it led to a new pursuit to exploit the utilization of biomass waste. This research aimed to study the potential of Cassava peel as raw material for bioethanol production. This study was performed in 2 main processes, acid hydrolysis, and fermentation. The experiment was initiated by conducting acid hydrolysis (100°C and 60 min) on Cassava peel’s starch using sulfonated carbon catalyst palm oil empty fruit bunch (5%-w/v) to produce 13.53 g/L glucose. The glucose contained hydrolysates then continued to ferment at 30°C. The effect of fermentation time (h), pH, and shaking rate (rpm) of cassava peel’s starch fermentation using Saccharomyces cerevisiae was analyzed. The best result was found at pH 4.5 and 50 rpm for a 24 h reaction with 3.75 g/L of bioethanol concentration. This study revealed that Cassava peel is a promising feedstock for biofuel production.

Assessment of POFA -Cementitious material as backfill barrier in DSRS borehole disposal: 226Ra confinement

Disused Sealed Radioactive Sources (DSRS) borehole disposal is an innovative concept recommended by international atomic energy agency (IAEA) to improve the safety and security of the management end point for these sources. A green application of Palm Oil Fuel Ash (POFA) as a supplementary material for cementitious backfill barrier in DSRS borehole disposal facility is proposed. Samples with up to 50% POFA replacement complied with the mechanical and hydraulic performance requirements for backfill barriers in retrievable radioactive waste disposal facilities. The structures of one year old OPC and optimum OPC-POFA cement backfills were evaluated using FESEM, XRD, EDXRF, BET, and TGA and their ²²⁶ Ra confinement performances were assessed. 30% POFA replacement improved the geochemical conditions by reducing competitive Ca²⁺ release into the disposal environment. It enhanced ²²⁶Ra confinement performance independently on the amount of water intrusion or releases below 2% of 1 Ci source. The improved performance is attributed to the higher fraction of active sites of OPC-POFA backfill compared to that of OPC backfill. ²²⁶Ra sorption onto C-S-H is irreversible, spontaneous, endothermic, and independent on the degree of the surface filling. The provided experimental data and theoretical analysis proved the feasibility of this green use of POFA in reducing the radiological hazard of ²²⁶Ra.

Synthesis of renewable heterogeneous acid catalyst from oil palm empty fruit bunch for glycerol-free biodiesel production

Interest in biodiesel research has escalated over the years due to dwindling fossil fuel reserves. The implementation of a carbon-based solid acid catalyst in biodiesel production eradicates the separation problems associated with homogeneous catalysis. However, its application in the glycerol-free interesterification process for biodiesel production is still rarely being studied in the literature. In this study, novel environmentally benign catalysts were prepared from oil palm empty fruit bunch (OPEFB) derived activated carbon (AC) which is sustainable and low cost via direct sulfonation using concentrated sulfuric acid. The effects of synthesizing variables such as carbonization and sulfonation temperatures with different holding times towards the fatty acid methyl ester (FAME) yield in interesterification reaction with oleic acid and methyl acetate were investigated in detail. It was found that the optimum carbonization temperature and duration together with sulfonation temperature and duration were 600 °C, 3 h, 100 °C and 6 h, respectively. The catalyst possessed an amorphous structure with a high total acid density of 9.0 mmol NaOH g^-1 due to the well-developed porous framework structure of the carbon support. Under these optimum conditions, the OPEFB derived solid acid catalyst recorded an excellent catalytic activity of 50.5% methyl oleate yield at 100 °C after 8 h with 50:1 methyl acetate to oleic acid molar ratio and 10 wt% catalyst dosage. The heterogeneous acid catalyst derived from OPEFB had shown promising properties that made them highly suitable for cost-effective and environmental-friendly glycerol-free biodiesel production.

The Potential and Status of Renewable Energy Development in Malaysia

The Malaysian Government has set an ambitious target to achieve a higher penetration of Renewable Energy (RE) in the Malaysian energy mix. To date, Malaysia has approximately 2% of its energy coming from RE generation sources compared to the total generation mix and targets achieving 20% penetration by 2025. The current energy mix for Malaysia power generation is mainly provided by natural gas and coal. The discussion will cover the traditional sources of generation including natural gas, coal and big hydro stations. In addition, the paper will cover in depth the potential of RE in the country, challenges, and opportunities in this sector. This study can give an initial evaluation of the Malaysian energy industry, especially for RE and can initiate further research and development in this area in order to support the Government target to achieve RE target of 20% by 2025.