Preferred Feedstock Research Articles

Migration and transformation pathways of chlorine and sulfur in producing pyrolytic biochar of a Zn/Cd-remediating plant amended with modified kaolin

Pyrolysis of metal-rich post-harvest biomass from remediation sites to produce green, value-added products has gained interest. However, the presence of Cl and S can trigger the migration and transformation of metals during biochar production, limiting its clean utilization. This study not only explored the pyrolysis potential of Pfaffia glomerata (PG) biomass but also quantified the migration and transformation of Zn, Cd, and their mineral phases and interactions with Cl and S in response to the additive use of kaolin versus its modified form (MK) through thermal pre-activation and acid impregnation. The MK exhibited a high relative enrichment factor (Ref) for Zn between 350–750 °C. Kaolin enhanced the immobilization of Cl and S in the solid biochar phase and promoted their removal from the gas phase. In particular, the additives promoted the SO2 and HCl emissions between 200–400 °C, possibly due to the competitive adsorption of Si and Al with K and Ca. Sulfur-binding to Ca indirectly influenced the fixation and stabilization of Zn and Cd. In contrast, Cl directly promoted the release of Zn and Cd at the high temperatures. The addition of MK significantly improved kaolin’s ability to adsorb and immobilize Zn and Cd within the biochar, thus mitigating their potential environmental risks. For predicting jointly optimal biochar yield and quality, a multi-response artificial neural network (ANN) outperformed single-response generalized regression and boosted ANN and identified PG or PG mixed with 10 % kaolin (PK91) as the preferred feedstock type, along with specific amounts of Si, S, Al, K, Ca, and Cl.

Assessment of Waste Animal Fats (WAFS) Biodiesel Production Potential as an Alternative Fuel for Zambia: A Case Study of Southern Province

The volatility in global fuel prices and the desire to reduce energy dependency on fossil fuels has necessitated the speeding up of alternative energy supply sources. Coupled to this is the global urgent need to reduce the accumulation of CO2 and green house gas (GHG) emissions as a result of fossil fuels production and use. Further, the mandate by united nations to move towards sustainably produced energy for the transportation, and power generation demands that we seek energy solutions that meet reduced negative impact on the environment. It is in this regard that this study seeks alternatives in waste animal fats (WAFs) biodiesel as an option that could meet the ever increasing demand for fossil fuel in the transport sector and power generation. For the transport sector and power generation , the biodiesel maybe blended with the fossil diesel in the approved ratios as stipulated by the Energy Regulation Board and the Zambia Bureau of Standards to help mitigate the net GHG and CO2 emissions. The biodiesel production in this study was based on the modified two-step process. These two steps involved passing the feedstock through esterification using sulphuric acid as catalyst and there after base catalysed using sodium hydroxide in a process referred to as transesterification. The resulting products in the esterification process are the esters and water whilst in the transesterification are the biodiesel and glycerol. The feedstock used are those of waste animal fats (WAFs) of cattle, pig and chicken that has been discarded from meat processing and animal slaughter houses. The feedstocks have been carefully selected based on the animals raised in the country with a bigger slaughtered population as well as reared. The population of animals reared and slaughtered annually are obtained from the Zambia Ministry of Agriculture animal population census records. Based on these records, the preferred feedstock sources where obtained. The study further 1. explored the economic potential of the biodiesel production for the Zambian government and beyond. 2. compared some of the characteristics of WAF biodiesel to that of imported fossil diesel 3. affirmed that WAF biodiesel has a very good impact in reducing environmental pollution as WAF dumping to land fills and the cost of disposal is reduced. Also,WAF biodiesel is bio-degradable. Thus, moving closer to an effective sustainable development as required by the united nations sustainability goals if full scale production is implemented in Zambia.

Obtaining phenolic-rich extracts from tree nut shells biomass by room temperature green extraction: Molecular insights and attribution analysis

The recycling of tree nut shells biomass (TNSB), a million-tons level inedible food waste, toward food and drug applications should be one of the most promising valorization pathways. However, therein biggest opportunity and challenge is to fully dig for treasure such as its own high-value biomacromolecules and natural active ingredients. This study completed a food and drug grade extraction by using five TNSB sample (i.e., walnut shell, hazelnut shell, macadamia shell, pin nut shell, and pistachio shell), two green solvents (water and ethanol), and cleaner room temperature green extraction (RTGE) technology; and revealed the molecular basis of the raw materials and their extracts through systematic and in-depth molecular analysis. The results showed that TNSB have extremely high lignin content, and their extracts (whether water or ethanol) are rich in phenolic compounds, which results in the latters having extremely strong antioxidant activities (comparable to vitamin C) and α-amylase inhibitory activities (comparable to acarbose). More specifically, walnut shell has the highest ever lignin content of 57% in all reported biomass. The water extract of walnut shell has more excellent properties, such as 147.65 mg/g of total reducing sugars (TRS), 60.49% of total phenolic content (TPC), 0.24 mg/mL of IC50, DPPH, 0.08 mg/mL of IC50, ABTS, and 13.44% of α-amylase inhibitory activity. Further molecular information shows that these reducing sugars are glucose, fructose, arabinose and fucose, and these phenolic compounds include phenol, vanillin, vanillic acid, p-hydroxybenzoic acid, gentisic acid, gallic acid, protocatechuic acid, epicatechin, caffeic acid, and (trans)catechin. These results demonstrate fully that TNSB will become the preferred feedstock species for lignin-first biorefinery in the future, and walnut shell is undoubtedly the best one. Furthermore, TNSB-based RTGE extracts have the potential to be developed into natural antioxidants, preservatives, diabetes-therapeutic pharmaceutical preparations, nutraceutical and functional foods. In addition, we also used XLSTAT software to conduct a systematic attribution analysis, namely, principal component analysis (PCA) and agglomerative hierarchical clustering (AHC), revealing the inner relationship between the multifactors including TRS, TPC, DPPH, ABTS and α-amylase inhibitory activity among TNSB species.

SOYBEAN AND WASTE COOKING OIL BASED FEEDSTOCKS AS A SUSTAINABLE BIOFUEL

Fuel in transportation is necessary and gas release from transportation activity raises concern of pollution. Sustainable fuels sources are from biomass can convert to the alternative to the bioenergy fuel. It is actively investigated with concern in the environmental effects if using conventional fuels from reservoir of fossil fuels. Hence, to counter these consequences, Sustainable Fuels (SF) is investigated as it is considered a renewable source of fuel. Thus, this study aims to establish an experiment to determine the suitability of biomass fuel by using soybean and waste cooking oil feedstocks. An experiment is set up to produce biomass fuel by using feedstock from different biomass particularly from soybean oil, a first-generation edible feedstock and waste cooking oil, a second-generation nonedible feedstock. The method chosen to produce biomass fuel is transesterification. The experiment will test the effects of a catalyst, namely solid Potassium Hydroxide, KOH, with three levels of concentration 0.75%, 1%, and 1.5% w/w KOH. Once the biomass fuel is produced it will undergo a series of tests to study the effect of parameters such as density, kinematic viscosity, caloric value, acid value and Fatty Acid Methyl Ester (FAME). The results show that using the feedstock 0.75 w/w% of KOH, the yield of biomass fuel is the most for both feedstocks. It is noted that soybean oil yields slightly greater feedstock than waste cooking oil. The density for both feedstock is very similar at 0.87-0.88 g/cm3. The acid value of biomass fuel produced from waste cooking oil is much higher than soybean oil at 0.28 but still under the acceptance range of 0.5. The concentration of catalyst used is a major factor in the yield of biomass fuel. It is also noted that the first-generation edible feedstock of soybean oil produces greater quality of biomass fuel. Nevertheless, first-generation feedstock still poses the food competition threat in comparison to second-generation feedstock. Therefore, establishment of the second-generation feedstock from waste cooking oil produces biomass fuel that is close to the quality of soybean oil, it is a more preferred feedstock compared to soybean oil.

Design of Experiments Study on Scottish Wood Biochars and Process Parameter Influence on Final Biochar Characteristics

Native Scottish wood samples were investigated as potential, locally sourced, raw materials for biochar production. Screening experiments identified pure softwood as the preferable feedstock. Influence of operational parameters, i.e. activating gas flow rate (CO2), heating ramp rate and contact time on final biochar characteristics, was investigated using design of experiments. Surface area and biochar yield were selected as response variables. Minitab was used to define experimental run conditions and suggested an optimal output at 60 min contact time and 15 °C/min ramp rate for maximum responses. The highest surface area (764 m2/g) was achieved at 850 °C from softwood, albeit with a low yield of 15%. Under optimised conditions, the observed surface area was 613 m2/g with ~ 18% yield. Pareto charts suggested no influence of gas flow rate on chosen responses, which correlated well with experimental data. Pore structure was a combination of micro- and mesopores with average pore widths of 3–5 nm and an average point of zero charge of 7.40 ± 0.02. Proximate analysis showed an increase in fixed carbon content from 20%, in the feedstock, to 80%, in the optimised biochar. Morphological analysis showed a layered carbon structure in the biochars. The results show the significance of the selected feedstock as a potential source of biochar material and the relevance of interplay of operational variables in biochar development and their final characteristics.

Bioreactors and biophoton-driven biohydrogen production strategies

Given the current issues with global warming and rising greenhouse gas emissions, biohydrogen is a viable alternative fuel option. Technologies to produce biohydrogen include photo fermentation, dark fermentation, direct and indirect bio-photolysis, and two-stage fermentation. Biological hydrogen generation is a green and promising technique with mild reaction conditions and low energy consumption compared to thermochemical and electrochemical hydrogen generation. To optimize hydrogen gas output using this method, the activity of hydrogen-consuming bacteria should be restricted during the production stages of hydrogen and acetate to prevent or limit hydrogen consumption. Raw material costs, poor hydrogen evolution rates, and large-scale output are the main limitations in biological hydrogen generation systems. Organic wastes would be the most preferred target feedstock for hydrogen fermentation, aside from biodegradable wastes, due to their high amount and simultaneous waste treatment advantage. This study examined the three primary methods for converting waste into bio-hydrogen: microbial electrolysis cell, thermochemical gasification, and biological fermentation, from both a technological and environmental standpoint. The effectiveness and applicability of these bioprocesses in terms of aspects influencing processes and their constraints are discussed. Alternative options for improving process efficiency, like microbial electrolysis, bio-augmentation, and multiple process integration, are also considered for industrial-level applications. Biohydrogen generation might be further enhanced by optimization of operating conditions and adding vital nutrients and nanoparticles. Cost reduction and durability enhancement are the most significant hindrances to fuel-cell commercialization. This review summarizes the biohydrogen production pathways, the impact of used organic waste sources, and bacteria. The work also addresses the essential factors, benefits, and challenges.

Life cycle analysis of biodiesel derived from fresh water microalgae and Karanja

Biodiesel is regarded as a feasible substitute for fossil fuel; thus, to fulfil the tremendous need for energy, potential non-edible feedstocks must be identified and assessed in terms of their environmental consequences and energy requirements for biodiesel production. Cradle to Grave life cycle approach (LCA) is currently being used to compare the environmental impacts and energy requirements of biodiesel obtained from two types of biodiesel feedstock i.e., Karanja (Pongamia Pinnata) and Microalgae. Sensitivity analysis was also performed to explore the influence of elements such as agricultural systems and energy sources on LCA systems in the given conditions. Karanja feedstock and microalgae have energy ratios of 3.57 and 0.45, respectively. GHG emissions from well to wheel for oil methyl esters derived from Karanja feedstock are estimated to be 63.81 gCO2eq/MJ, while microalgae feedstock emissions are 85.37 gCO2eq/MJ. According to the sensitivity study, both emission and energy estimates were significantly sensitive to biodiesel output. Karanja excelled in all GHG-emitting processes, with reduced GHG emissions and a greater energy ratio. Microalgae, on the other hand, would be the preferable feedstock in the long run since it has demonstrated competitive performance in terms of carbon dioxide emissions, and energy ratio, and has no detrimental influence on the food cycle.

Best options for large-scale production of liquid biofuels by value chain modelling: A New Zealand case study

Biofuels are a promising low-carbon replacement for fossil fuels in the transport sector. However, how should a country without an existing biofuel industry, such as New Zealand, go about implementing large-scale production and use of biofuels? We used value chain modelling and optimisation to identify lowest-cost options to replace existing liquid fossil fuels used in New Zealand, and how to make the transition. Multiple scenarios, e.g. 5–50% biofuel substitution, different land use assumptions, were examined. Novel features were added to the Biomass Value Chain Model to consider the impacts of land quality on biomass production, land use competition, existing and new plantation forests, and replacements for multiple liquid fossil fuels used. Credible routes exist for large-scale biofuel production in New Zealand, which could contribute significantly to meeting its GHG reduction targets. Key results include (i) Lowest cost substitution of 30% of fossil fuel use by 2050 reduced GHG emissions by 80% at a levelized cost within the range of prices seen for imported fossil petrol and diesel over the last 10 years; (ii) Drop-in biofuels from non-food feedstocks, particularly forestry on non-arable land, are the most attractive in the long term; and (iii) Pyrolysis plus upgrading of lignocellulosic feedstocks and biodiesel from canola were amongst the lowest-cost conversion options. The most important contributors to the cost are the: conversion process capital and operating costs; delivered cost of feedstock(s) suitable for each process; conversion yields; and options for co-product sales and distributed processing. Land use decisions, conditioned by land prices, affected the preferred feedstocks, but also where biomass was grown and converted into fuels, fuel costs, and GHG reductions. Conversion plant locations were driven by feedstock availability and costs through time and existing infrastructure.

Biorefinery Cascade Processing for Converting Corncob to Xylooligosaccharides and Glucose by Maleic Acid Pretreatment.

Corncob as an abundant and low-cost waste resource has received increasing attention to produce value-added chemicals, it is rich in xylan and regarded as the most preferable feedstock for preparing high value addedxylooligosaccharides. The use of xylooligosaccharides as core products can cut costs and improve the economic efficiency in biorefinery. In this study, maleic acid, as a non-toxic and edible acidic catalyst, was employed to pretreat corncob and produce xylooligosaccharides. Firstly, the response surface methodology experimental procedure was employed to maximize the yield of the xylooligosaccharides; a yield of 52.9% (w/v) was achieved with 0.5% maleic acid (w/v) at 155 °C for 26min. In addition, maleic acid pretreatment was also beneficial to enhance the enzymatic hydrolysis efficiency, resulting in an enzymatic glucose yield of 85.4% (w/v) with a total of 10% solids loading. Finally, a total of 160g of xylooligosaccharides and 275g glucose could be produced from 1000g corncob starting from the maleic acid pretreatment. Overall, a cascade processing for converting corncob to xylooligosaccharides and glucose by sequential maleic acid pretreatment and enzymatic hydrolysis was successfully designed for the corncob wastes utilization.

Waste-Based Second-Generation Bioethanol: A Solution for Future Energy Crisis

The demand for more environmentally friendly alternative renewable fuels is growing as fossil fuel resources are depleting significantly. Consequently, bioethanol has attracted interest as a potentially viable fuel. The key steps in second-generation bioethanol production include pretreatment, saccharification, and fermentation. The present study employed simultaneous saccharification and fermentation (SSF) of cellulose through bacterial pathways to generate second-generation bioethanol utilizing corncobs and paper waste as lignocellulosic biomass. Mechanical and chemical pretreatments were applied to both biomasses. Then, two bacterial strains, Bacillus sp. and Norcadiopsis sp., hydrolysed the pretreated biomass and fermented it along with Achromobacter sp., which was isolated and characterized from a previous study. Bioethanol production followed by 72 h of biomass hydrolysis employing Bacillus sp. and Norcadiopsis sp., and then 72 h of fermentation using Achromobacter sp. Using solid phase micro extraction combined with GCMS the ethanol content was quantified. SSF of alkaline pretreated paper waste hydrolysed by Bacillus sp. following the fermentation by Achromobacter sp. showed the maximum ethanol percentage of 0.734±0.154. Alkaline pretreated corncobs hydrolyzed by Norcadiopsis sp. yielded the lowest ethanol percentage of 0.155±0.154. The results of the study revealed that paper waste is the preferred feedstock for generating second-generation bioethanol. To study the possible use of ethanol-diesel blends as an alternative biofuel E2, E5, E7, and E10 blend emulsions were prepared mixing commercially available diesel with ethanol. The evaluated physico-chemical characteristics of the ethanol-diesel emulsions fulfilled the Ceypetco requirements except for the flashpoint revealing that the lower ethanol-diesel blends are a promising alternative to transport fuels. As a result, the current study suggests that second generation bioethanol could be used as a renewable energy source to help alleviate the energy crisis..

Carbon-based catalyst for environmental bioremediation and sustainability: Updates and perspectives on techno-economics and life cycle assessment

Global rise in the generation of waste has caused an enormous environmental concern and waste management problem. The untreated carbon rich waste serves as a breeding ground for pathogens and thus strategies for production of carbon rich biochar from waste by employing different thermochemical routes namely hydrothermal carbonization, hydrothermal liquefaction and pyrolysis has been of interest by researchers globally. Biochar has been globally produced due to its diverse applications from environmental bioremediation to energy storage. Also, several factors affect the production of biochar including feedstock/biomass type, moisture content, heating rate, and temperature. Recently the application of biochar has increased tremendously owing to the cost effectiveness and eco-friendly nature. Thus this communication summarized and highlights the preferred feedstock for optimized biochar yield along with the factor influencing the production. This review provides a close view on biochar activation approaches and synthesis techniques. The application of biochar in environmental remediation, composting, as a catalyst, and in energy storage has been reviewed. These informative findings were supported with an overview of lifecycle and techno-economical assessments in the production of these carbon based catalysts. Integrated closed loop approaches towards biochar generation with lesser/zero landfill waste for safeguarding the environment has also been discussed. Lastly the research gaps were identified and the future perspectives have been elucidated.

The interaction among gut microbes, the intestinal barrier and short chain fatty acids.

The mammalian gut is inhabited by a massive and complicated microbial community, in which the host achieves a stable symbiotic environment through the interdependence, coordination, reciprocal constraints and participation in an immune response. The interaction between the host gut and the microbiota is essential for maintaining and achieving the homeostasis of the organism. Consequently, gut homeostasis is pivotal in safeguarding the growth and development and potential productive performance of the host. As metabolites of microorganisms, short chain fatty acids are not only the preferred energy metabolic feedstock for host intestinal epithelial cells, but also exert vital effects on antioxidants and the regulation of intestinal community homeostasis. Herein, we summarize the effects of intestinal microorganisms on the host gut and the mechanisms of action of short chain fatty acids on the four intestinal barriers of the organism, which will shed light on the manipulation of the intestinal community to achieve precise nutrition for specific individuals and provide a novel perspective for the prevention and treatment of diseases.

Metabolic engineering strategies to enable microbial utilization of C1 feedstocks.

One-carbon (C1) substrates are preferred feedstocks for the biomanufacturing industry and have recently gained attention owing to their natural abundance, low production cost and availability as industrial by-products. However, native pathways to utilize these substrates are absent in most biotechnologically relevant microorganisms. Recent advances in synthetic biology, genome engineering and laboratory evolution are enabling the first steps towards the creation of synthetic C1-utilizing microorganisms. Here, we briefly review the native metabolism of methane, methanol, CO2, CO and formate, and how these C1-utilizing pathways can be engineered into heterologous hosts. In addition, this review analyses the potential, the challenges and the perspectives of C1-based biomanufacturing.

A stakeholders’ participatory approach to multi-criteria assessment of sustainable aviation fuels production pathways

Sustainable aviation fuels (SAF) provide a viable option to decarbonise global aviation. Unlike conventional jet-fuel, SAFs can be produced in several production pathways making their selection a complex multi-criteria decision making (MCDM) problem with conflicting objectives. In this paper, we propose a multicriteria based framework for evaluating SAF production pathways, which is a sequential decision-making process with feedback adjustment mechanisms. Given the early stage of SAF technologies' development and the scarcity of data on such technologies, in this research, we involved a variety of aviation industry stakeholders to assist with data and preference gathering. Our MCDM framework is designed to be generic to provide flexibilities to potential users in choosing the appropriate implementation decisions for the relevant stakeholders. The strength of the proposed framework lays in its flexibility to accommodate various stakeholders' subjective judgements, choice of ranking method, and robustness of results. We used our MCDM framework within a stakeholders’ participatory approach to rank order 11 SAF production pathways against 24 criteria grouped under social, environmental, economic, and technical impact categories. Our analysis revealed that the environmental and the economic impact categories are the most important ones followed by the technical and the social criteria; the gasification/Fischer-Tropsch (F-T) based production processes are preferred over fermentation and oil-based ones; and waste gases are the preferred feedstock along with wood-residue. These findings provide decision-makers with guidelines on the selection of SAF production pathways.

An assessment of the utilization of waste apple slurry in bio-succinic acid and bioenergy production

Recognizing the importance of succinic acid as one of the most relevant platform molecules, the present study assesses the production of succinic acid from waste apple slurry/pomace as a sustainable and renewable feedstock. The assessment has been undertaken by incorporating technical and economic considerations in the analysis while also comparing two succinic acid production scenarios. The aforementioned considerations have been applied by utilizing process simulation results, generated from Aspen Plus software, as input data to undertake economic assessments using classic economic correlations. Employing well-defined system boundaries, scenarios to produce bio-succinic acid with either bioelectricity (scenario 1) or biogas (scenario 2) as co-products were therefore comparatively accessed. This study was able to demonstrate that waste pomace as a feedstock has the potential to generate low-cost succinic acid, while scenario 2 constituted the preferred pathway overall. This study results may provide valuable information to policy makers, to enable better decisions regarding the viability, design and execution of large-scale bio-succinic acid production projects based on waste apple pomace as the preferred feedstock.

The choice of feedstock for the biodiesel production with optimal physicochemical and low-temperature properties

The transesterification reaction of sunflower, mustard and linseed oil with ethyl alcohol was studied using potassium hydroxide as a catalyst. The physicochemical properties and low-temperature characteristics of the feedstock and obtained products were studied. The most preferred feedstock for the biodiesel fuel production had been determined.

Transformations of stable gas condensate hydrocarbons into high-octane gasoline components over ZSM-5 zeolite catalyst

The process of stable gas condensate zeoforming was implemented at the laboratory scale under the conditions of varying feedstock composition and technological parameters (temperature, pressure, feedstock flow rate). The directions of hydrocarbon transformations were established. The influence of technological parameters on the composition and properties of the obtained product was estimated. From the perspective of involving the obtained zeoforming product into production of motor gasoline, optimal technological parameters were determined (the temperature of 375 °C, the pressure of 2.5 MPa, the feedstock flow rate of 2 h−1), the most preferred feedstock was established (the feedstock, which contains high amount of naphthenes, which sufficiently influence aromatization reaction). The recipes for motor gasoline blending were developed using the zeoforming product as the major component for the production of different grades, such as RON-92, RON-95, RON-98, meeting the modern specifications.

CHARACTERIZATION OF UNTREATED AND COMPOSTED BIOCHAR DERIVED FROM ORANGE AND PINEAPPLE PEELS

Biochar production is a waste management option for agro-businesses and it is widely used to sequester carbon and to improve soil fertility. The preferred feedstock to produce biochar has been lignin and cellulose rich materials, or a mixture of industrial or animal residues. However, residues rich in soluble sugars, pectin and polysaccharides, such as fruit wastes, have been rarely used and are widely available. Furthermore, the release of toxic compounds has been reported when untreated biochars are used as soil amendments. Here we test if composting is able to eliminate toxicants and to improve biochar characteristics. We produced biochar out of orange and pineapple peels by pyrolysis, and characterized the physical and chemical properties of untreated and composted biochars. The analyses show that the untreated biochar has a high soluble salt and C content, an alkaline nature and high porosity. The composting process increased the pH, micronutrients, exchangeable cations, oxygen-based functional groups and the labile carbon, and reduced the PAHs and dioxins. Our results reveal that orange and pineapple peels are suitable raw materials for producing biochar but should be composted before using them as soil amendments.

Plant Phenylalanine/Tyrosine Ammonia-lyases.

Aromatic amino acid deaminases are key enzymes mediating carbon flux from primary to secondary metabolism in plants. Recent studies have uncovered a tyrosine ammonia-lyase that contributes to the typical characteristics of grass cell walls and contributes to about 50% of the total lignin synthesized by the plant. Grasses are currently preferred bioenergy feedstocks and lignin is the most important limiting factor in the conversion of plant biomass to liquid biofuels, as well as being an abundant renewable carbon source that can be industrially exploited. Further research on the structure, evolution, regulation, and biological function of functionally distinct ammonia-lyases has multiple implications for improving the economics of the agri-food and biofuel industries.

Energy Recovery from Anaerobic Digestion of Banana Peels

Bananas are tropical fruits mostly eaten in Malaysia. The banana peels are high in organic, and putrescible caused the odour and leachate problem where it has been a dump. In practice, banana peels considered as a waste product that has been combined with municipal solid waste and dumped into the landfills. However, banana peels are bountiful in organic matter and high with moisture content. Thus, it could be a convincing substrate for biogas production through anaerobic digestion so that the major concerns of environmental protection is achieved aside from producing energy in a sustainable way. Therefore, this study was initiated to estimate the ultimate methane yield from the unripe banana peel (UBP) and ripe banana peel (RBP). Besides that, the assessment on the kinetics of the methane production from UBP and RBP is conducted using Modified Gompertz and first-order kinetic modelling. In this study, the anaerobic digestibility of banana peels measured in a batch reactor for 25 days each fed by UBP and RBP. The batch reactors operated at an inoculum to substrate ratio (I/S) of 1.0 and at a mesophilic temperature (37°C). The ultimate methane yields from UBP and RBP digestion were 847.57mLCH4/gVS and 1405.31mLCH4/gVS, respectively. The higher bioavailability (in term of COD, and solid) in RBP resulted in the higher methane production rate. Two first-order and modified Gompertz kinetic models were compared for the prediction of organic degradation, and the results indicated that the first-order kinetic model of the RBP fitted the experiment best. It concluded that ripe banana peels are the most preferable feedstock for the anaerobic digestion.