Biodiesel production from jatropha oil (Jatropha curcas) with high free fatty acids: An optimized process

Response surface methodology (RSM) based on central composite rotatable design (CCRD) was used to optimize the three important reaction variables—methanol quantity (M), acid concentration (C) and reaction time (T) for reduction of free fatty acid (FFA) content of the oil to around 1% as compared to methanol quantity (M′) and reaction time (T′) and for carrying out transesterification of the pretreated oil. Using RSM, quadratic polynomial equations were obtained for predicting acid value and transesterification. Verification experiments confirmed the validity of both the predicted models. The optimum combination for reducing the FFA of Jatropha curcas oil from 14% to less than 1% was found to be 1.43% v/v H₂SO₄ acid catalyst, 0.28 v/v methanol-to-oil ratio and 88-min reaction time at a reaction temperature of 60 °C as compared to 0.16 v/v methanol-to-pretreated oil ratio and 24 min of reaction time at a reaction temperature of 60 °C for producing biodiesel. This process gave an average yield of biodiesel more than 99%. The fuel properties of jatropha biodiesel so obtained were found to be comparable to those of diesel and confirming to the American and European standards.     

Biodiesel production from Jatropha curcas oil

In view of the fast depletion of fossil fuel, the search for alternative fuels has become inevitable, looking at huge demand of diesel for transportation sector, captive power generation and agricultural sector, the biodiesel is being viewed a substitute of diesel. The vegetable oils, fats, grease are the source of feedstocks for the production of biodiesel. Significant work has been reported on the kinetics of transesterification of edible vegetable oils but little work is reported on non-edible oils. Out of various non-edible oil resources, Jatropha curcas oil (JCO) is considered as future feedstocks for biodiesel production in India and limited work is reported on the kinetics of transesterification of high FFA containing oil. The present study reports a review of kinetics of biodiesel production. The paper also reveals the results of kinetics study of two-step acid–base catalyzed transesterification process carried out at pre-determined optimum temperature of 65 and 50 °C for esterification and transesterification process, respectively, under the optimum condition of methanol to oil ratio of 3:7 (v/v), catalyst concentration 1% (w/w) for H₂SO₄ and NaOH and 400 rpm of stirring. The yield of methyl ester (ME) has been used to study the effect of different parameters. The maximum yield of 21.2% of ME during esterification and 90.1% from transesterification of pretreated JCO has been obtained. This is the first study of its kind dealing with simplified kinetics of two-step acid–base catalyzed transesterification process carried at optimum temperature of both the steps which took about 6 h for complete conversion of TG to ME.     

Biodiesel production by esterification of palm fatty acid distillate

Production of fatty acid methyl ester (FAME) from palm fatty acid distillate (PFAD) having high free fatty acids (FFA) was investigated in this work. Batch esterifications of PFAD were carried out to study the influence of: including reaction temperatures of 70–100 °C, molar ratios of methanol to PFAD of 0.4:1–12:1, quantity of catalysts of 0–5.502% (wt of sulfuric acid/wt of PFAD) and reaction times of 15–240 min. The optimum condition for the continuous esterification process (CSTR) was molar ratio of methanol to PFAD at 8:1 with 1.834 wt% of H₂SO₄ at 70 °C under its own pressure with a retention time of 60 min. The amount of FFA was reduced from 93 wt% to less than 2 wt% at the end of the esterification process. The FAME was purified by neutralization with 3 M sodium hydroxide in water solution at a reaction temperature of 80 °C for 15 min followed by transesterification process with 0.396 M sodium hydroxide in methanol solution at a reaction temperature of 65 °C for 15 min. The final FAME product met with the Thai biodiesel quality standard, and ASTM D6751-02.     

Evaluation of solar photo-Fenton parameters on the pre-oxidation of leachates from a sanitary landfill

The main purpose of this work is to study the treatment of a leachate after preliminary aerated lagooning by a solar photo-Fenton process, using a photocatalytic reactor with compound parabolic collectors (CPCs). The influence of different process parameters in the reaction rate was evaluated, such as, the type of acid used in the acidification step (H₂SO₄, HCl, H₂SO₄ + HCl); type of iron salt (FeSO₄, FeCl₃) and respective iron concentration (60, 80, 100 and 140 mg Fe²⁺/L); temperature; and ratio of illuminated to total volume (25 L/35 L; 25 L/72 L). DOC abatement in the acidification procedure is independent of the type of acid used and temperature, and is related principally with the precipitation of humic acids. The use of HCl alone or in combination with H₂SO₄ leads to a substantially increase of the chloride ions, leading to the formation of less reactive chloride radicals when compared with sulfate radicals, decreasing the photo-Fenton reaction rate. The use of ferrous ions instead of ferric ions influenced positively the photo-Fenton reaction. Meteorological conditions favoring higher temperature of the leachate enhance the photo-Fenton reaction. Alternating dark and illumination intervals has shown a negligible effect on the illumination time needed to achieve the same mineralization, indicating that the Fenton process that takes place in dark zones is not efficient, even in the degradation of intermediate compounds resulting from the light-enhanced reaction. According to biodegradability tests, the optimum energy dose, necessary to obtain a biodegradable effluent, is 57.4 kJ_UV/L, consuming 120 mM of H₂O₂ and leading to a final DOC of 284 mg/L which corresponds to approximately 66% of mineralization.     

An experimental and kinetic modeling study of three butene isomers pyrolysis at low pressure

Pyrolysis of three butene isomers (C₄H₈) including 1-butene (1-C₄H₈), 2-butene (2-C₄H₈) and i-butene (iC₄H₈) were studied from 900 to 1900 K at low pressure. Synchrotron vacuum ultraviolet (VUV) photoionization mass spectrometry with molecular-beam sampling technique was used for isomeric identification of products and intermediates and also for concentration measurement. Based on the experimental results, a kinetic model consisting of 76 species and 232 reactions was developed to simulate mole fractions of species. The mole fraction profiles of pyrolysis species predicted by the model are in good agreement with the experimental measurements. The decomposition pathways of C₄H₈ are illustrated according to the reaction flux analysis. Our analysis demonstrates that reaction sequences 1-C₄H₈ → aC₃H₅ → aC₃H₄ → pC₃H₄ → C₂H₂, 2-C₄H₈ → saxC₄H₇ → 1,3-C₄H₆ → C₂H₃ → C₂H₂ and iC₄H₈ → iC₄H₇ → aC₃H₄ → pC₃H₄ → C₂H₂ are the major decomposition pathways of 1-butene, 2-butene and i-butene, respectively.     

The effects of different additives in electrolyte of AGM batteries on self-discharge

Hydrogen and oxygen evolution at the negative and positive electrodes in AGM batteries are the main reasons of self-discharging. The self-discharge of five AGM batteries was investigated by measuring different potential between two electrodes during 48 days. Five different battery electrolytes were used including 35% (w/w) H₂SO₄ without additives and the remaining contain 7.1, 9.94, and 21.3 g l⁻¹ sodium sulfate, 4 g l⁻¹ boric acid, 3 g l⁻¹ citric acid, and finally 0.7 and 1 g l⁻¹ stearic acid except one containing boric acid that the concentration of H₂SO₄ was 36% (w/w). The results revealed that the rate of self-discharge for battery without additive was 0.01 V day⁻¹. The battery with boric acid showed the lowest rate of self-discharge with 0.0025 V day⁻¹. It was also found that stearic and citric acids are comparatively appropriate additives for decreasing the self-discharge. They caused a decrease of the self-discharge rate to 0.005 and 0.0075 V day⁻¹ on appropriate concentration, respectively. In compared to other additives, sodium sulfate showed to be not an appropriate additive for decreasing battery self-discharging. The rate of 0.03 V day⁻¹ of self-discharging was obtained for the battery containing all selected concentration of sodium sulfate during first 4 days of measuring.     

Influence of H2SO4 concentration on the mechanism of the processes and on the electrochemical activity of the Pb/PbO2/PbSO4 electrode

The aim of the present investigation is to study the influence of H₂SO₄ concentration on the electrochemical activity, the phase composition and the structure and morphology of the PbO₂ particles. The study is performed through cycling (between 700 and 1600 mV versus Hg/Hg₂SO₄ electrode) of a Pb/PbO₂/PbSO₄ electrode immersed in sulfuric acid solutions of various concentrations (ranging within 2 orders of magnitude: 6.0–0.05 M H₂SO₄). In this concentration region, sulfuric acid dissociates in two steps resulting in the formation of HSO₄⁻ and SO₄²⁻ ions, respectively. It has been established experimentally that the electrochemical activity of the PbO₂/PbSO₄ electrode depends on the concentration of HSO₄⁻ ions in the solution. Three acid concentration regions can be distinguished: (a) active acid concentration region (5.0 M > C_H2SO4 > 0.5 M), where the concentration of HSO₄⁻ ions is the highest and a βPbO₂ phase is formed; PbO₂ particles are drop-like in shape and contain large hydrated (gel) zones; the electrode has the highest capacity; (b) passive high concentration region (C_H2SO4 > 5.0 M), where the concentration of HSO₄⁻ ions decreases at the expense of formation of H₂SO₄ molecules; crystal-shaped αPbO₂ particles are formed; the capacity of the electrode declines; (c) passive low concentration region (C_H2SO4 < 0.5 M), where the concentration of HSO₄⁻ ions decreases at the expense of the formation of SO₄²⁻ ions; the content of αPbO₂ in the anodic layer increases; PbO₂ particles are crystal-shaped and are interconnected in dendrites; the capacity of the electrode declines. The above electrochemical behavior of the PbO₂/PbSO₄ electrode is explained by the mechanism of the reactions in the gel zones of the PbO₂ particles and by the influence of HSO₄⁻ ions on the number of electrochemically active particles. On grounds of the obtained experimental results it has been established that the working interval within which the C_H2SO4 may change on cycling is from 5.0 to 1.5 M, i.e. 3.5 M H₂SO₄ per 1 l of H₂SO₄ solution with s.g. 1.28 takes part in the reactions on both battery plates. This is the maximum amount of H₂SO₄ in the solution that would have no detrimental effect on the positive plates of the lead-acid battery.     

Biodiesel production by esterification of oleic acid with short-chain alcohols under ultrasonic irradiation condition

Production of fatty acid ethyl ester (FAEE) from oleic acid (FFA) with short-chain alcohols (ethanol, propanol, and butanol) under ultrasonic irradiation was investigated in this work. Batch esterification of oleic acid was carried out to study the effect of: test temperatures of 10–60 °C, molar ratios of alcohol to oleic acid of 1:1–10:1, quantity of catalysts of 0.5–10% (wt of sulfuric acid/wt of oleic acid) and irradiation times of 10 h. The optimum condition for the esterification process was molar ratio of alcohol to oleic acid at 3:1 with 5 wt% of H₂SO₄ at 60 °C with an irradiation time of 2 h.     

Deposition of ZrO2 film by liquid phase deposition

In this study, undoped ZrO₂ thin films were deposited on single-crystal silicon substrates using liquid phase deposition. The undoped films were formed by hydrolysis of zirconium sulfate (Zr(SO₄)₂·4H₂O) in the presence of H₂O. A continuous oxide film was obtained by controlling adequate (NH₄)₂S₂O₈ concentration. The deposited films were characterized by SEM, FT-IR, XRD and DTA. Typically, the films showed excellent adhesion to the substrate with uniform particle diameter about 150 nm. The thicknesses of ZrO₂ film were about 200 nm after 10 h deposition at 30 °C. These films shows single tetragonal phase after heat treated at 600 °C. High annealing temperature (e.g. 750 °C) may result in the phase transformation of (t)-ZrO₂ into (m)-ZrO₂.     

Electrocatalysis of oxygen reduction on carbon supported Ru-based catalysts in a polymer electrolyte fuel cell

Powder of nanosized particles of Ru-based (Ru_x, Ru_xSe_y and Ru_xFe_ySe_z) clusters were prepared as catalysts for oxygen reduction in 0.5 M H₂SO₄ and for fuel cells prepared by pyrolysis in organic solvent. These electrocatalysts show a high uniformity of agglomerated nanometric particles. The reaction kinetics were studied using rotating disk electrodes and an enhanced catalytic activity for the powders containing selenium and iron was observed. The Ru-based electrocatalysts were used as the cathode in a single prototype PEM fuel cell, which was prepared by spray deposition of the catalyst on the surface of Nafion^® 117 membranes. The electrochemical performance of each single fuel cell was compared to that of a platinum/platinum conventional membrane electrode assembly (MEA), using hydrogen and oxygen feed streams. A maximum power density of 140 mW cm⁻², at 80 °C with 460 mA cm⁻² was obtained for the Ru_xFe_ySe_z catalysts; approximately 55% lower power density than that obtained with platinum.     

Effect of Fe2P on the electron conductivity and electrochemical performance of LiFePO4 synthesized by mechanical alloying using Fe3+ raw material

LiFePO₄ and LiFePO₄/Fe₂P composites have been produced using raw Fe₂O₃ materials by mechanical alloying (MA) and subsequent firing at 900 °C. The LiFePO₄ prepared by firing at 900 °C for 30 min showed a maximum discharge capacity of 160 mAh g⁻¹ at C/20, which is at a higher capacity and improved cell performance compared with the LiFePO₄ prepared using for a longer firing times. LiFePO₄/Fe₂P composites have been synthesized by the reduction reaction of phosphate in excess of carbon. By transmission electron microscopy (TEM) and scanning electron microscopy (SEM) it was determined that the LiFePO₄ phase was agglomerated with a primary particle size of 40–50 nm around the surface of Fe₂P with particle size of 200 nm. The electronic conductivity of the LiFePO₄/Fe₂P composite increased in proportion with the amount that the Fe₂P phase and discharge capacity increased during the cycling. The sample containing 8% of Fe₂P in LiFePO₄/Fe₂P composite showed a high discharge capacity and rate capability at high current.     

Shock tube studies of methyl butanoate pyrolysis with relevance to biodiesel

Methyl butanoate pyrolysis and decomposition pathways were studied in detail by measuring concentration time-histories of CO, CO₂, CH₃, and C₂H₄ using shock tube/laser absorption methods. Experiments were conducted behind reflected shock waves at temperatures of 1200–1800 K and pressures near 1.5 atm using mixtures of 0.1%, 0.5%, and 1% methyl butanoate in Argon. A novel laser diagnostic was developed to measure CO in the ν₁ fundamental vibrational band near 4.56 μm using a new generation of quantum-cascade lasers. Wavelength modulation spectroscopy with second-harmonic detection (WMS-2f) was used to measure CO₂ near 2752 nm. Methyl radical was measured using UV laser absorption near 216 nm, and ethylene was monitored using IR gas laser absorption near 10.53 μm. An accurate methyl butanoate model is critical in the development of mechanisms for larger methyl esters, and the measured time-histories provide kinetic targets and strong constraints for the refinement of the methyl butanoate reaction mechanism. Measured CO mole fractions reach plateau values that are the same as the initial fuel mole fraction at temperatures higher than 1500 K over the maximum measurement time of 2 ms or less. Two recent kinetic mechanisms are compared with the measured data and the possible reasons for this 1:1 ratio between MB and CO are discussed. Based on these discussions, it is expected that similar CO/fuel and CO₂/fuel ratios for biodiesel molecules, particularly saturated components of biodiesel, should occur.     

Production of bioethanol and associated by-products from potato starch residue stream by Saccharomyces cerevisiae

Potato starch residue stream produced during chips manufacturing was used as an economical source for biomass and bioethanol production by Saccharomyces cerevisiae. Results demonstrated that 1% H₂SO₄ at 100 °C for 1 h was enough to hydrolyze all starch contained in the residue stream. Two strains of S. cerevisiae (y-1646 and commercial one) were able to utilize and ferment the acid-treated residue stream under both aerobic and semi-anaerobic conditions. The maximum yield of ethanol (5.52 g L^?1) was achieved at 35 °C by S. cerevisiae y-1646 after 36 h when ZnCl₂ (0.4 g L^?1) was added. Addition of NH₄NO₃ as a source of nitrogen did not significantly affect either growth or ethanol production by S. cerevisiae y-1646. Some secondary by-products including alcohol derivatives and medical active compound were found to be associated with the ethanol production process.     

Preparation and electrochemical studies of Fe-doped Li3V2(PO4)3 cathode materials for lithium-ion batteries

The Fe-doped Li₃V₂(PO₄)₃ cathode materials for Li-ion batteries were synthesized by a conventional solid-state reaction, and the Fe-doping effects on the Li electrochemical extraction/insertion performance of Li₃V₂(PO₄)₃ were investigated by galvanostatic charge/discharge and cyclic voltammetry measurements. The optimal Fe-doping content x is 0.02–0.04 in Li₃Fe_xV_2−x(PO₄)₃ system. The Fe-doped Li₃V₂(PO₄)₃ samples showed a better cyclic ability between 3.0 and 4.9 V, for example, the discharge capacity of Li₃Fe_0.02V_1.98(PO₄)₃ was 177 mAh g⁻¹ in the 1st cycle and 126 mAh g⁻¹ in the 80th cycle. The retention rate of discharge capacity is about 71%, much higher than 58% of the undoped system. The improved electrochemical performances of the Li₃V₂(PO₄)₃ could be attributed to the increased electrical conductivity and structural stability deriving from the incorporation of the Fe³⁺ ions.     

Solar thermochemical process for hydrogen production using ferrites

A two-step water splitting process using the ZnFe₂O₄/Zn/Fe₃O₄ reaction system was proposed for H₂ generation utilizing concentrated solar heat. The mixture of Zn and Fe₃O₄ was heated to 873 K in flowing steam with an Ar carrier gas, and the H₂ gas was generated at 93.4% of the theoretical yield for the reaction of 3Zn+2Fe₃O₄+4H₂O=3ZnFe₂O₄+4H₂ (H₂ generation step). The XRD and Mössbauer spectroscopy showed that the Zn‐submitted ferrite (Zn_xFe_3−xO₄; 0.2≤x≤1) (main solid product) and ZnO (minor) were formed in the solid products after the H₂ generation reaction. The ZnFe₂O₄ product, which was formed after the H₂ generation step during the two-step water splitting process with the ZnFe₂O₄/Zn/Fe₃O₄ system, could be decomposed into Zn (and ZnO) and Fe₃O₄ by the Xe beam irradiation at 1900 K after 3 min with a 67.8% yield for the reaction of 3ZnFe₂O₄=3Zn+2Fe₃O₄+2O₂ (O₂ releasing step=solar thermal step).     

Catalytic oxidation of methanol on molybdate-modified platinum electrode in sulfuric acid solution

The catalysis of methanol oxidation on molybdate-modified platinum was studied by using linear sweep voltammetry (LSV), cyclic voltammetry (CV) and chronoamperometry in the solutions with H₂SO₄ concentrations from 0.5 to 4.5 M. It was found that methanol oxidation was catalyzed on the modified platinum by lowering methanol oxidation potential and promoting methanol oxidation current. There was the strongest catalysis in 3.7 M H₂SO₄ solution. In this solution, methanol oxidation took place on the modified platinum at the potential 0.2 V more negatively than on the non-modified platinum and the steady oxidation current of methanol on the modified platinum at 0.7 V versus SCE was 10 times that on the non-modified platinum. Molybdates were reduced to adsorbed hydrogen molybdenum(IV) bronzes on platinum in H₂SO₄ solution at a very negative potential. The amount of reduced molybdates decreased with decreasing H₂SO₄ concentrations. The reduced molybdates were oxidized to different forms of hydrogen molybdenum bronzes (H_xMoO₃, 0<x<2) depending on the H₂SO₄ concentration. Platinum was modified by these hydrogen molybdenum bronzes, but under-modified in the solution with lower H₂SO₄ concentration and over-modified in the solution with higher H₂SO₄ concentration. The catalysis of methanol oxidation was weakened when the platinum was under- or over-modified.     

Hydrogen production from steam and autothermal reforming of LPG over high surface area ceria

Steam and autothermal reforming reactions of LPG (propane/butane) over high surface area CeO₂ (CeO₂ (HSA)) synthesized by a surfactant-assisted approach were studied under solid oxide fuel cell (SOFC) operating conditions. The catalyst provides significantly higher reforming reactivity and excellent resistance toward carbon deposition compared to the conventional Ni/Al₂O₃. These benefits of CeO₂ are due to the redox property of this material. During the reforming process, the gas–solid reactions between the hydrocarbons present in the system (i.e. C₄H₁₀, C₃H₈, C₂H₆, C₂H₄, and CH₄) and the lattice oxygen (O_O^x) take place on the ceria surface. The reactions of these adsorbed surface hydrocarbons with the lattice oxygen (C_nH_m + O_O^x → nCO + m/2(H₂) + V_O + 2e′) can produce synthesis gas (CO and H₂) and also prevent the formation of carbon species from hydrocarbons decomposition reactions (C_nH_m ⇔ nC + 2mH₂). Afterwards, the lattice oxygen (O_O^x) can be regenerated by reaction with the steam present in the system (H₂O + V_O + 2e′ ⇔ O_O^x + H₂). It should be noted that V_O denotes as an oxygen vacancy with an effective charge 2⁺.At 900 °C, the main products from steam reforming over CeO₂ (HSA) were H₂, CO, CO₂, and CH₄ with a small amount of C₂H₄. The addition of oxygen in autothermal reforming was found to reduce the degree of carbon deposition and improve product selectivities by completely eliminating C₂H₄ formation. The major consideration in the autothermal reforming operation is the O₂/LPG (O/C molar ratio) ratio, as the presence of a too high oxygen concentration could oxidize the hydrogen and carbon monoxide produced from the steam reforming. A suitable O/C molar ratio for autothermal reforming of CeO₂ (HSA) was 0.6.     

A shock tube study of the rate constants of HO2 and CH3 reactions

HO₂ and CH₃ are major intermediate species presented during the oxidation of natural gas at intermediate temperatures and high pressures. Previous theoretical calculations have identified several product channels for HO₂ and CH₃ reactions, with CH₃ + HO₂ → CH₃O + OH and CH₃ + HO₂ → CH₄ + O₂ being the dominant reaction pathways. Both reaction pathways play an important role in the kinetics of CH₄ oxidation as CH₃ + HO₂ → CH₃O + OH is a chain-branching reaction whereas CH₃ + HO₂ → CH₄ + O₂ a chain termination reaction.H₂O₂/CH₄/Ar mixtures were shock-heated to a temperature between 1054 and 1249 K near 3.5 atm to initiate the reaction. OH radicals yielded from H₂O₂ thermal decomposition react with H₂O₂ and CH₄ respectively to produce HO₂ and CH₃ in the reacting system. Using laser absorption spectroscopy, time-histories of H₂O, OH and HO₂ were measured behind reflected shock waves. The rate constant of reaction CH₃ + HO₂ → CH₃O + OH was determined to be 6.8 × 10¹² cm³ mol^?1 s^?1 with an uncertainty factor of 1.4. The rate constant of the competing CH₃ + HO₂ → CH₄ + O₂ reaction was determined to be 4.4 × 10¹² cm³ mol^?1 s^?1, with an uncertainty factor of 2.1. In addition, the rate constants of two other major reactions of the reacting system, H₂O₂ (+M) → 2OH (+M) and OH + CH₄ → CH₃O + OH, were found to have excellent agreement with values recommended in literature.     

Elaboration of a new anode material for all-solid state Zn/MnO2 protonic cells

A new composite consisting of a mixture of zinc and hydrated ammonium zinc sulfate, Tutton salt, has been elaborated and studied as anode material for all-solid state protonic cells. The results obtained point out the ability of (NH₄)₂Zn(SO₄)₂·6H₂O double salt to concomitantly exchange protons with the solid proton conducting electrolyte and accommodate Zn²⁺ cations issued from oxidation. Such features have been evinced by thermal and crystallographic characterizations. The anode composition has been optimized through a kinetic study on a three-electrode type-cell, showing that a 35 wt.% salt-based composite displays the minimum polarization. Zn/MnO₂ cells prepared using such a composite anode achieve relatively high specific capacity and energy of, more than 30 Ah kg⁻¹ and 40 Wh kg⁻¹, respectively.     

Biodiesel production from swine manure via housefly larvae (Musca domestica L.)

Although biodiesel is a sustainable and renewable diesel fuel, the current feedstock predominantly from edible oils limits the economic feasibility of biodiesel production and thus the development of a cost-effective non-food feedstock is really essential. In this study, approximately 21.6% of crude grease was extracted from housefly (Musca domestica L.) larvae reared on swine manure, and the extracted grease was evaluated for biodiesel production concerning the variables affecting the yield of acid-catalyzed production of methyl esters and the properties of the housefly larvae-based biodiesel. The optimized process of 8:1 methanol/grease (mol/mol) with 2 vol% H₂SO₄ reacted at 70 °C for 2 h resulted in a 95.7% conversion rate from free fatty acid (FFA) into methyl esters. A 90.3% conversion rate of triglycerides (crude grease) to its esters was obtained from alkaline trans-esterification using sodium hydroxide as catalyst. The major fatty acid components of this larvae grease were palmitic (29.1%), oleic (23.3%), palmitoletic (17.4%) and linoleic (17.2%). The housefly larvae-based biodiesel has reached the ASTM D6751-10 standard in density (881 kg/m³), viscosity (5.64 mm²/s), ester content (96.8%), flash point (145 °C), and cetane number (52). These findings suggest that the grease derived from swine manure-grown housefly larvae can be a feasible non-food feedstock for biodiesel production.