Highest Biodiesel Yield Research Articles

Application of response surface methodology for the optimisation of biodiesel production from Jatropha-algae oil blend

The transesterification technique is used to produce methyl esters from jatropha-algae oil. The effect of four variables on higher biodiesel yield, such as molar ratio, reaction temperature, catalyst amount and reaction duration, is calculated, and the process is optimised using Response surface methodology based on Box–Behnken Design. At a molar ratio of 1:10, reaction temperature of 53°C, 0.3% by weight. Percent catalyst, and reaction duration of 172 min, an optimum biodiesel yield of 96% is attained. With a relative error of 4% of the experimental outcomes, the projected optimal conditions were experimentally validated (96%). The ANOVA P value of 0.0001 indicates that the model is significant.

CaO-MgFe2O4@K2CO3 as a novel and retrievable nanocatalyst for two-step transesterification of used frying oils to biodiesel

In this study, biodiesel was generated from used frying oil (UFO) in the presence of CaO-MgFe2O4 @K2CO3 as a novel and effective nanocatalyst. Structural and morphological properties of CaO, CaO-MgFe2O4, and CaO-MgFe2O4 @K2CO3 nanocatalysts were evaluated by EDX/SEM, BET, FTIR, TEM, DLS, VSM, and XRD analyses. Also, life cycle assessment and reaction mechanism were investigated. The utmost biodiesel yield using CaO and CaO-MgFe2O4 @K2CO3 nanocatalysts was acheived 93.55% and 96.53%, respectively, at a alcohol/oil ratio of 15:1 for CaO and 18:1 for CaO-MgFe2O4 @K2CO3, catalyst percentage of 4%, temperature of 70 °C, and reaction time of 5 h, which indicates a significant increase in the biodiesel yield of CaO-MgFe2O4 @K2CO3 compared to CaO. Also, physical features of biodiesel such as density, viscosity, flashpoint, cetane number, pour point and cloudpoint were 882 kg/m3, 4.4 mm2/s, 168 ºC, 58.82, 3 ºC and − 2 ºC, respectively, which are within international standards. Moreover, thermodynamic and kinetic behaviors of transesterification were studied and the results showed that the biodiesel generation process using CaO-MgFe2O4 @K2CO3 is endothermic (ΔH°= 61.9 kJ/mol) and non-spontaneous (ΔG°>0). The activation energy of the transesterification reaction was 64.62 kJ/mol, showing the significant potential of the catalyst in the transesterification reaction. Besides, the reusability of CaO-MgFe2O4 @K2CO3 nanocatalyst showed that it can be used in 4 reuse cycles with high biodiesel yield (>90%). Life cycle assessment showed that CaO-MgFe2O4 @K2CO3 has less negative impacts on the environment than common catalysts such as KOH and NaOH. Also, collecting UFO and using it in biodiesel generation helps to reduce environmental pollution.

In-situ synergistic effect of ultrasonic irradiation and solvent addition for enhancing CaO catalyzed transesterification

This work focuses on the improvement of biodiesel production with the addition of solvents (acetone, THF, and methyl myristate) in CaO catalyzed transesterification of palm oil and methanol in an ultrasonic reactor using a methanol to oil molar ratio of 9:1, reaction temperature of 60 °C, and CaO loading of 5 and 10 wt%. The addition of acetone and THF in the presence of ultrasonic irradiation expressed the synergistic effect which can accelerate the initial transesterification rate by increasing the solubility and in-situ generations of microbubble droplets and calcium glyceroxide as a new active species. The addition of methyl myristate enhanced the biodiesel yield by acting as an emulsifier of the reaction mixture and producing microemulsion droplets with the help of ultrasonic irradiation. Moreover, the mixed acetone and methyl myristate with existing ultrasonic irradiation can promote CaO catalyzed transesterification by accelerating the initial rate and achieving a high biodiesel yield (97.3%). The quality of the synthesized biodiesel in terms of physical properties is proven to meet the biodiesel standard.

The effect of different drying methods and microalgae species on the quality parameters of biodiesel obtained by transesterification technique

In the study, seven microalgae species called Nitzschia sp., Nannochloropsis sp., Botryococcus braunii, Neochloris oleoabundans, Schizochytrium sp., Chlorella vulgaris L., and Chlorella variabiilis L. were dried by four drying methods: spray, convective, vacuum, and microwave. Biodiesel was produced from dried microalgae via transesterification.The vegetable oil yield was the maximum in spray and vacuum dried Schizochytrium with 35.50 and %34.53, respectively. Similarly, the highest biodiesel yield with 100% was obtained in Schizochytrium dried by spray technique. However, the cloud point of −1.77 °C was the lowest in Botryococcus braunii samples dehydrated by microwave drying. The highest pour point with −10.13 °C was obtained in microwave dried Chlorella variabilis samples, but the maximum freezing point was found in the microwave and convective dried samples of Chlorella variabilis with −13.60 and −13.70 °C, respectively. The lowest water content was measured in biodiesel samples from Botryococcus braunii, Chlorella vulgaris, and Chlorella variabilis dried by microwave technique. However, the best results regarding calorific value were found in Schizochytrium samples dried by spray and vacuum. The viscosity with 6.08 mm2 s−1 and density with 0.90 g cm−3 of Botryococcus braunii dried by the microwave method were at the maximum.Interestingly, two species commonly used in biodiesel production, Chlorella vulgaris and Chlorella variabilis, could not meet the expectations regarding quality parameters. Also, Schizochytrium and Nitzschia were determined as the most suitable microalgae species for the quality standards for biodiesel production. Compared to the others, the most successful results were obtained in the biodiesel produced from Schizochytrium dried spray drying.

Fusion-Assisted Hydrothermal Synthesis and Post-Synthesis Modification of Mesoporous Hydroxy Sodalite Zeolite Prepared from Waste Coal Fly Ash for Biodiesel Production

Increases in biodiesel prices remains a challenge, mainly due to the high cost of conventional oil feedstocks used during biodiesel production and the challenges associated with using homogeneous catalysts in the process. This study investigated the conversion of waste-derived black soldier fly (BSF) maggot oil feedstock over hydroxy sodalite (HS) zeolite synthesized from waste coal fly ash (CFA) in biodiesel production. The zeolite product prepared after fusion of CFA followed by hydrothermal synthesis (F-HS) resulted in a highly crystalline, mesoporous F-HS zeolite with a considerable surface area of 45 m2/g. The impact of post-synthesis modification of the parent HS catalyst (F-HS) by ion exchange with an alkali source (KOH) on its performance in biodiesel production was investigated. The parent F-HS zeolite catalyst resulted in a high biodiesel yield of 84.10%, with a good quality of 65% fatty acid methyl ester (FAME) content and fuel characteristics compliant with standard biodiesel specifications. After ion exchange, the modified HS zeolite catalyst (K/F-HS) decreased in crystallinity, mesoporosity and total surface area. The K/F-HS catalyst resulted in sub-standard biodiesel of 51.50% FAME content. Hence, contrary to various studies, the ion exchange modified zeolite was unfavorable as a catalyst for biodiesel production. Interestingly, the F-HS zeolite derived from waste CFA showed a favorable performance as a heterogeneous catalyst compared to the conventional sodium hydroxide (NaOH) homogeneous catalyst. The zeolite catalyst resulted in a more profitable process using BSF maggot oil and was economically comparable with NaOH for every kilogram of biodiesel produced. Furthermore, this study showed the potential to address the overall biodiesel production cost challenge via the development of waste-derived catalysts and BSF maggot oil as low-cost feedstock alternatives.

High efficient conversion of Cannabis sativa L. biomass into bioenergy by using green tungsten oxide nano-catalyst towards carbon neutrality

Current study focuses on the utilization of non-edible oil seeds of Cannabis sativa as an economical feedstock for synthesizing high quality biodiesel using novel, green and extremely reactive tungsten oxide (WO3) nano catalyst. The as synthesized green nanoparticles (NPs) were examined using Fourier-transform infrared spectroscopy (FT-IR), X-ray Diffraction (XRD), energy diffraction X-ray (EDX) and scanning electron microscopy (SEM). Results showed that WO3 has spherical crystal structure with a diameter of 45 nm. Highest biodiesel yield (91 wt%) was achieved under dynamic conditions i.e., 2 wt% catalyst, 1:7 oil to methanol molar ratio, 80 °C reaction temperature for 120 min. The reaction conditions were optimized via Response Surface Methodology. WO3 NPs showed catalytic stability up to five rounds. The fuel characteristics of biodiesel met the values set by international standards. Non-edible Cannabis sativa seed oil and novel green WO3 nano-catalyst are economical choices to assist the sustainable growth of biodiesel industry.

Exploration of agricultural residue ash as a solid green heterogeneous base catalyst for biodiesel production

AbstractBiodiesel is an economical and nonpolluting green fuel produced from the transesterification of oil and alcohol in the presence of a catalyst. Transesterification of vegetable oils with conventional (homogeneous) catalysts for biodiesel production is considered to have a promising future but they are nonrenewable and hazardous. The major setback is the increase in cost of production. High production cost, in terms of feedstock oil and catalyst acquisition is one of the major challenges facing the global commercialization and acceptance of biodiesel. Heterogeneous solid catalysts are currently replacing homogeneous catalysts because of their ability to overcome hurdles associated with homogeneous catalysts. This study discussed the development and feasibility of calcined ash from agricultural residues as a solid green heterogeneous base catalyst for biodiesel production without chemical degradation. Solid‐calcined ash based catalysts are being developed primarily via calcination at suitable temperatures and have been used as catalysts without mixing with carrier compounds. The various agricultural residues used and the corresponding biodiesel yields were also discussed. The study also looked at some agricultural residues that could be targeted for high catalytic output. It was found that high biodiesel yields (80%–98%) were achieved with most of the crude oil raw materials used. The catalyst could be reused at least five (5) times. From the discussed literature, it was found that the current state of biodiesel production can be improved by using heterogeneous base catalysts made from agricultural residue calcined ash.

The optimization of tetrahydrofuran as a co-solvent on biodiesel production from rubber seeds using response surface methodology

The present work aims to investigate the impact of tetrahydrofuran as a co-solvent on biodiesel production from rubber seeds to accelerate the transesterification reaction with a high biodiesel yield. We extracted the oil from rubber seeds before being reacted with methanol to synthesize biodiesel. It reveals that the composition of rubber seed oil was palmitic acid of 9.71 %, stearic acid of 13.09 %, oleic acid of 19.23 %, linoleic acid of 37.49 %, and linolenic acid of 20.47 %. The esterification process was examined to diminish the FFA content from 5.00 % to 1.99 %. The transesterification process was then examined to convert the triglycerides of rubber seed oil into biodiesel. The process variables in the transesterification were defined by Box Behnken Design, and the optimum condition was evaluated by response surface methodology. We found that the optimum condition was at temperature of 52 °C, reaction time of 30 min, and mass ratio of tetrahydrofuran to methanol of 1.4:1 to achieve a biodiesel yield of 97 %. The result suggests that the addition of tetrahydrofuran as a co-solvent accelerated the transesterification reaction of rubber seed oil with an excellent biodiesel yield.

Biomass-derived hydrophobic metal-organic frameworks solid acid for green efficient catalytic esterification of oleic acid at low temperatures

Biodiesel, of great significance, is a promising kind of non-polluting renewable energy that can meet world energy needs. However, the by-product water of esterification reaction used for biodiesel production is not conducive to the positive reaction, and even destroys the activity and structure of the used catalyst. In this study, a renewable solid acid catalyst FDCA/SA-Hf with a degree of hydrophobicity was simply prepared by a solvent-free assembly manner using biomass-based materials. FDCA/SA-Hf was found to be efficient for producing biodiesel from the abundant free fatty acid and nonedible raw oils at a low temperature, and its reaction mechanism was also studied. FDCA/SA-Hf showed stable structural properties and excellent hydrophobic network (131.5°), wherein the chemical grafting of stearic acid improved its Lewis acidity and promoted the adsorption of free fatty acid and the desorption of water. Importantly, as promoted by FDCA/SA-Hf in esterification, a high biodiesel yield reached 98.6% (49 °C, 4.1 wt%, 19.5:1 and 9.5 h). After being easily reused, biodiesel yield still achieved 90% even in the presence of 6 wt% water or after six cycles, which was due to the high hydrophobicity and stability. FDCA/SA-Hf shows great potential in heterogeneous acid-mediated catalytic fields, especially for biodiesel production.

The production of bio-based fuels and carbon catalysts from chicken waste

From an environmental and economic perspective, converting harmful waste materials into value-added products is very important. This work explores using an equal mixture of chicken waste (CW) and chicken bones (CBs) as a raw material for creating more valuable products. The CW (chicken skin and fat) were de-fatted, and their solid residue leftover was blended with CBs and utilized as a pyrolysis feedstock to create bio-oil (BO) and bio-char (BC). The waste blend was thermally pyrolyzed over a range of temperatures (400–600 °C) and periods (30–150 min) numerous range of heating rates (5–20 °C/min). The highest yield of liquid fractions (61.60%) was achieved at 500 °C for 120 min at a 10 °C/min rate of heating. The BO content of the liquid fraction amounted to 25.225%. According to the FTIR outcomes, the produced BO is a complex mixture of many organic compounds, including carboxylic acids, aldehydes, ketones, esters, and hydrocarbons (alkanes, alkenes, cyclic compounds, etc.). The fuel characteristics of the synthetic BO were similar to those reported for numerous samples of BO in the literature. It also offered its suitability as a synthetic fuel for engines and a probable source of chemical feedstock. The BC leftover after the pyrolysis of the waste mixture was exploited as catalyst support. It was impregnated with different ratios (10–50%) of KOH. The typical sample (40K/BC) was identified by SABET, FE-SEM, EDX, XRD, and FTIR spectroscopy. The efficiency and performance of the 40K/BC catalyst for transesterification of a blend of chicken fat and waste cooking oil to biodiesel (BD) were explored under diverse operating conditions. The highest BD yield (94.88%) was obtained in 90 min at 60 °C reaction temperature using a 4.0 wt% 40K/BC catalyst and 9:1methanol: lipid blend molar ratio. Additionally, the developed catalyst (40K/BC) demonstrated sustained activity after five cycles of recycling and reusing with a BD yield of >84.0%. The BD characteristics met the requirements of ASTM D6751 and EN 14,214. The ester content in the BD amounted to 96.36% based on 1HNMR analysis.

Experimental Studies on Transesterification of Mango (Mangifera indica) Seed Kernel Butter for Biodiesel Production

This research study involves transesterification of mango seed kernel butter using methanol as solvent and Tetra Hydro Furan (THF) was used as co-solvent in converting biodiesel. High density and higher acid value in biodiesel cause less thermal efficiency in the engine. The percentage yield of biodiesel has been studied under various parameters such as the molar ratio of methanol: oil, type of alkali catalyst and catalyst concentration (%). As the significant results, the highest biodiesel yield% was attained using the molar ratio of methanol to mango seed oil at 7:1 using sodium hydroxide as alkali catalyst with the catalyst concentration of 1.0% and THF co-solvent. The maximum %yield obtained was 90.79%. The produced biodiesel was characterized by Gas Chromatography-Mass Spectrometry (GC-MS). The properties of biodiesel were analysed, such as freezing point, acid value, saponification value, density, and specific gravity with the respective values of 15, 0.85 mg/g, 70.13 mg/g, 788 kg/m3, and 0.788, 11 fatty acid methyl esters were found in different concentrations. Analysis of Variance (ANOVA) has been used as a statistical method for optimization to validate the results obtained. The biodiesel results met the ASTM-D6751 and EN14214 standards for use as a working fluid.

Optimization and kinetics studies of biodiesel synthesis from Jatropha curcas oil under the application of eco-friendly microwave heating technique: an environmentally benign and sustainable bio-waste management approach

This study attempts to synthesize biodiesel as a green liquid fuel from Jatropha curcas oil (JCO) utilizing waste eggshell (WES) as an effective and excellent sustainable source of the heterogeneous catalyst under the application of environmentally benign microwave heating technique. After preparing the CaO-based catalyst, diverse characterization techniques such as X-Ray Diffraction, Energy Dispersive Spectroscopy, Scanning Electron Microscopy, Fourier Transform Infrared, and Brunauer–Emmett–Teller were employed for characterization measurements. Under different optimized conditions, a considerable high biodiesel yield of 92% was attained while employing the following reaction conditions; methanol to oil molar ratio of 9:1, 5 wt% catalyst loading, 165 min reaction time with a microwave power of 800 W, and a 65 °C reaction temperature. The developed catalyst had significantly retained its reusability up to the 5th cycle of reuse. The catalysed transesterification process's activation energy of 38.5 kJ mol−1 demonstrated that the reaction is chemically controlled. Therefore, the WES has been utilized as a renewable base heterogeneous catalyst for novel biodiesel synthesis from JCO, which can be applied in diesel engines to lessen air pollution, specifically pollutant emissions from diesel vehicles. The results of this study are not for academic purposes only. They can also serve as models for industrial biodiesel production by exploiting bio-waste as catalysts and non-edible oils as feedstocks in microwave heating systems as environmentally friendly chemistry systems. In addition, our study uses non-consumable oil feedstock and bio-waste materials in an economical way to produce biofuel while contributing to environmental sustainability and sustainable bio-waste management. This approach extends to the existing state-of-the-art research.

Membrane based reactors for sustainable treatment of Coronopus didymus L. by developing Iodine doped potassium oxide Catalyst under Dynamic conditions.

Green nano-technology together with the availability of eco-friendly and alternative sources are the promising candidates to combat environment deteriorations and energy clutches globally. The current work focuses on the synthesis and application of newly synthesized nano catalyst of Iodine doped Potassium oxide I (K2O) for producing sustainable biodiesel from novel non-edible seed oils of Coronopus didymus L. using membrane based contactor to avoid emulsification and phase separation issues. Highest biodiesel yield (97.03%) was obtained under optimum conditions of 12:1 methanol to oil ratio, reaction temperature of 65 °C for 150min with the 1.0wt% catalyst concentration. The lately synthesized, environment friendly and recyclable Iodine doped Potassium oxide K (IO)2 catalyst was synthesized via chemical method followed by characterization via advanced techniques including EDX, XRD, FTIR and SEM analysis. The catalyst was proved to be stable and efficient with the reusability of five times in transesterification reaction. These analysis have reported the sustainability, stability and good quality of biodiesel from seed oil of Coronopus didymus L. using efficient Iodine doped potassium oxide catalyst. Thus, non-edible, environment friendly and novel Coronopus didymus L. seeds and their extracted oil along with Iodine doped potassium oxide catalyst seems to be highly affective, sustainable and better alternative source to the future biodiesel industry. Also, by altering the reaction equilibrium and lowering the purification phases of the process, these studies show the potential of coupling transesterification and a membrane contactor.

Biodiesel Production from Waste Frying Oil using Catalysts Derived from Waste Materials

Domestic resources such as vegetable oil, animal fats, tallows, and waste frying oil are common raw materials for making biodiesel. In contrast to ordinary diesel, biodiesel helps to reduce CO2 emissions. This study aimed to produce biodiesel using waste frying oil in the presence of suitable solid waste-derived heterogeneous catalysts. Firstly, CaO/K2O catalyst was synthesised using eggshells and banana peels. Then, the pre-prepared catalyst (CaO/K2O) modified with ZnO was utilized for biodiesel production. The prepared catalyst and biodiesel were characterized using X-ray diffraction (XRD) and FTIR spectroscopy. The AOAC and ASTM standard methods were employed to analyze the physicochemical properties of oils and biodiesel. The catalytic efficiency of CaO/K2O and CaO/K2O-ZnO tested for the transesterification of purified oil to biodiesel at the catalyst weight (1-7 %wt), temperature (60-80°C), and methanol to oil ratios ranging from 3:1 to 12:1. The highest biodiesel yield (92%) obtained when 5 %wt CaO/K2O catalyst used. However, a 95% yield resulted when using a 3 %wt CaO/K2O-ZnO catalyst load in 2 h with a methanol to oil (v/v) ratio of 9:1 at 65°C. The study revealed that waste frying oil is a good source of biodiesel which could replace nonrenewable energy in the future. The catalysts made from solid waste could also replace an expensive chemical catalyst.

Optimization of Biodiesel Production from Beef Tallow Using Microwave Assisted

The need for fuel in Indonesia is increasing every year. Renewable and environmentally friendly alternative fuels are the right choice to meet national energy need and can substitute fossil fuels. Biodiesel has been widely applied in diesel engines that run on diesel fuel. Biodiesel is processed from plant and animal oils or fats. Non-edible oil is preferable to be processed into biodiesel because it doesn’t interfere with food availability. Beef tallow has abundant availability, the users are still few, and has an ALB content of <1%, making it suitable as a raw material for biodiesel. The transesterification reaction to process oil (triglycerides) into biodiesel (methyl ester) requires effective heating, one of which is the microwave method. Optimal process conditions are required to produce high biodiesel yields. Therefore, the data optimization process is carried out in order to obtain the optimum conditions and save the number of running. In this study using the reaction temperature and catalyst concentration (%weight) as independent variable. The fixed variables and were the mole ratio of methanol: oil (6:1), reaction time (20 minutes), power (200 watt) and stirring speed (200 rpm). Data analysis of optimization used the Response Surface Methodology (RSM) based on Central Composite Design (CCD) with the help of the software STASTICA 10. The research results the optimum yield was 98.736% at conditions of reaction temperature 74.142ºC and catalyst 0.396%weight. Mathematical equation for optimum conditions y = 90.81073 - 8.74778 X1.

Membrane Performance on Biodiesel Production and Purification: A Review

Biodiesel is considered as a renewable and cleaner fuel compared to the equivalent fossil fuels. However, the conventional methods of biodiesel production as well as its purification processes present economic and environmental limitations. Membrane based systems can significantly improve biodiesel yield retaining the unrecovered feedstock and recycle it to the reactor for further esterification/transesterification. Moreover, the simultaneous removal of byproducts leads in high purity and quality biodiesel production. The current study presents recent experimental and modeling results based on a PRISMA literature review analysis. Several membrane-based catalytic systems were categorized by their performance and stability on biodiesel production as well as by their biodiesel purification for glycerol removal. Findings indicated that high biodiesel yield can be achieved by using catalytic synthesized membranes of different materials; while their stability presents high rate after several runs in batch mode or continuous running mode. In the purification process, glycerol removal over filtration membrane systems seems to be a viable solution for obtaining high quality biodiesel and avoiding wet washing methods that result in wastewater generation. Membrane technology contributes in biodiesel production and purification processes enhancing cost reduction and environmental protection. Nevertheless, more research is required for further industrialization.

Effective utilization of azolla filiculoides for biodiesel generation using graphene oxide nano catalyst derived from agro-waste

A circular bioeconomy is concerned with environmental sustainability and waste valorization. Utilization of leftovers and trashes while elevating the value of biomass through the cascade is receiving greater attention in recent years. Biomass is expected to play a significant role in fixing global alternative fuel ambitions. Azolla, a type of macroalgae which grows very quickly, is employed to develop a self-sustaining Azolla biorefinery model. Tannery effluents are treated using the phytoremediation approach, and the algal oil extracted from the cultivated Azolla is employed to produce bio-diesel as an alternative energy source. Biodiesel is produced via the transesterification technique. N2 sorption isotherms, scanning electron microscopy (SEM), FT-IR, and X-ray diffraction studies are used to evaluate the catalyst. The IR spectral analysis with the absorption bands corresponding to alkyl and ester stretching and bending modes of vibrations confirm biodiesel production. The reaction mechanism involved in the conversion process is proposed, and the process parameters such as the reaction temperature, oil-to-methanol molar ratio, and catalyst quantity are optimized. The results show that a catalyst loading of 2 % (by weight) and a molar ratio of 1:9 produce a high biodiesel yield with GO as the catalyst at temperatures between 60 and 65 °C. Its ability to catalyze allowed for numerous cycles of repetitive use. The results show that employing GO as a catalyst to trans esterify Azolla oil to biodiesel is cost-effective and reliable.

Ultrasound-assisted biodiesel generation from waste edible oil using CoFe2O4@GO as a superior and reclaimable nanocatalyst: Optimization of two-step transesterification by RSM

In current study, CoFe2O4@graphene oxide (GO) and CoFe2O4 heterogeneous nanocatalysts were successfully synthesized using the ultrasonic method and then used to generate biodiesel from waste edible oil (WEO) in a two-step transesterification process. To do so, the catalysts surface was characterized using CO2-TPD, SEM, EDX/Map, XRD, VSM, BET, FTIR, and DLS analyses. Also, central composite design (CCD) was utilized to optimize the impact of various factors on biodiesel generation. With the help of ultrasonication, the highest biodiesel yield using CoFe2O4 (91.64%) and CoFe2O4@GO (98.17%) was achieved at time of 55.75 min, temperature of 64.75 °C, methanol/oil ratio of 16.05:1 and catalyst concentration of 5.22 wt%. Also, the highest biodiesel yield without ultrasonication using CoFe2O4 and CoFe2O4@GO were gained as 58.96 and 67.13%, respectively. Moreover, the highest predicted biodiesel yield in the presence of CoFe2O4@GO by the RSM-CCD method is 98.95%, which is the maximum biodiesel yield ever achieved from WEO. The outcomes show that ultrasound-assisted transesterification is an efficient method for biodiesel generation, which can reduce costs and production time. After 5 reuse cycles, the CoFe2O4@GO nanocatalyst showed a yield of about 90%, which is due to its desirable magnetic attributes and easy separation. According to international standards and using FT-IR and HNMR analyses, the biodiesel produced can be used in diesel engines without further modification. Besides, kinetic and thermodynamics studies indicated that the generation reaction of biodiesel using both nanocatalysts is endothermic and non-spontaneous.

Biodiesel production from Azadirachta India-derived oil by electrolysis technique: Process optimization using response surface methodology (RSM)

Biodiesel production from non-edible seed oil of abundantly available wild Azadirachta India through novel electrolysis technique assisted (trans)esterification was studied at room temperature. The response surface methodology (RSM) based on the central composite design (CCD) was applied with a three-parameter-three-level to optimize the operating condition, including voltage (5–15 V/cm), time (1−3h), and methanol to oil molar ratio (5:1–20:1). Based on experimental design, a quadratic model was developed. The effects of each parameter on the biodiesel production yield were discussed. The experimental results and optimum condition of the additional independent experiments were in good agreement with the predicted results of the model. The highest biodiesel yield was 28% without catalyst and 80% using an acidic catalyst. The optimum condition was as follows: time of 2 h, voltage of 15 V/cm, methanol to oil molar of 20:1, THF to oil molar ratio of 10:1, NaCl weight of 1 wt%, 2 wt% distilled water based on the total weight of solution, room temperature and H2SO4 catalyst weight of 16 wt%. Overall, non-edible Azadirachta India seed oil appeared to be applicable feedstock for the future biodiesel industry. By sensitivity analysis of significant parameters, the electrolysis technique is highly recommended as an efficient method to industrialize biodiesel production at ambient temperature.

Optimized biodiesel production from waste cooking oil using a functionalized bio-based heterogeneous catalyst

Bio-based waste materials are important sources of elements such as calcium and potassium that can be used as active phases for preparing heterogeneous catalysts for biodiesel production. In this study, the potential of a composite bio-based heterogeneous catalyst of fused crab shell and plantain peels was assessed for the transesterification of waste cooking oil. The catalyst and the precursor materials were characterized to assess their structural, compositional, morphological and thermal characteristics. Biodiesel production was carried out via a single step transesterification process while the experimental variables were optimized using response surface methodology (RSM). The morphological properties revealed an aggregated catalyst surface with clearly defined pores. The catalyst was bifunctional as evidenced by the presence of basic (calcium and potassium) and acidic oxides (silicon and iron). The catalyst had a high surface area (260.35 m 2 /g) and pore volume (0.65 cm 3 /g) which contributed to the maximum biodiesel yield of 93% obtained at a reaction temperature of 60 °C, catalyst loading of 5 wt%, reaction time of 149.94 min and methanol to oil ratio of 13.03:1. The RSM model was found to be very adequate in modeling biodiesel production (R 2 = 0.9939). The catalyst was highly stable with high biodiesel yields (>80%) recorded after six cycles. The properties of the biodiesel were found to be comparable with standards. The synthesized catalyst holds numerous advantages over conventional catalysts because of its reusability, ease of synthesis, stability, high surface area and ready availability of the precursor materials. • A composite catalyst was synthesized from crab shell and plantain peels for biodiesel production from waste cooking oil. • The catalyst displayed high activity with bifunctionality. • Biodiesel production was modeled and optimized using RSM. • Biodiesel yield of 93% was obtained from waste cooking oil via transesterification. • The biodiesel produced satisfied ASTM D6571 and EN 14214 standard specifications.