Biodiesel Conversion Research Articles

Magnetically recoverable Mg substituted zinc ferrite nanocatalyst for biodiesel production: Process optimization, kinetic and thermodynamic analysis

The purpose of this work is to develop a magnetically recoverable magnesium substituted zinc ferrite nanocatalysts for production of biodiesel from waste cooking oil. Microwave assisted combustion process were employed to synthesis the nanocatalyst. The catalyst were characterized by XRD, FTIR, HR-SEM, EDX, DRS and VSM analysis. The VSM study revealed a relatively high magnetic moment and high saturation magnetization property useful for magnetic separation of the catalyst from the reaction medium. Biodiesel conversion of 99.9% was achieved at the optimized reaction conditions like 3 wt% of Mg2+ doped ZnFe2O4 nanocatalyst (ZnMgF5 sample), reaction temperature about 65ᵒC, methanol-oil molar ratio of 18:1 and reaction time 30 min. Investigation on the transesterification kinetics using ZnMgF5 revealed the rate constants ranging from 0.0375 min−1 to 0.2382 min−1, activation energy Eg = 52 kJ mol−1 and frequency factor A = 2.31 × 107 min−1. The negative values of entropy (ΔS°) indicates, increased randomness of the system. Thermodynamic parameters ΔG° = 87.17 kJ mol−1 at 338 K and ΔH° = 49.31 kJ mol−1 indicate that the transesterification reaction is non-spontaneous and endothermic in nature. The magnetically separated catalyst retained 94% of biodiesel yield even after ten cycles of recovery showing a very good performance.

Lipase-Catalyzed Synthesis of Glycerol-Free Biodiesel from Rapeseed Oil and Dimethyl Carbonate

The enzymatic production of glycerol-free biodiesel by the transesterification of rapeseed oil was studied using lipase as catalyst. A series of co-solvents were employed in an attempt to improve reaction kinetics. The effects of the reaction conditions (molar ratio of dimethyl carbonate (DMC) and rapeseed oil, type of lipases, amount of lipases, solvent effects, reaction temperature and time) on the conversion and yield of biodiesel and glycerol carbonate (GC) were investigated. The optimal conditions for biodiesel and GC were 20% Novozym 435, 3:1 molar ratio of DMC to rapeseed oil, and with 20% [Omim][BF6] as solvent. Under these conditions, the conversions of 88.51% biodiesel and 73.87% GC have been achieved after 48 h. The biodiesel and GC conversions were eight times higher compared to the conventional solvent-free system, respectively. There was no obvious loss in the biodiesel and GC yield after Novozym 435 having been used for five recycling.

Advancing biodiesel production from microalgae Spirulina sp. by a simultaneous extraction–transesterification process using palm oil as a co-solvent of methanol

AbstractMicroalgae have been considered as a potential candidate for biodiesel feedstock. Single-stage simultaneous extraction–transesterification process is proposed for simpler and more effective biodiesel conversion. In this study, the experiment of biodiesel production from microalgae Spirulina sp. was performed in a batch-stirred reactor using palm oil as a co-solvent of methanol and catalyzed by potassium hydroxide at a percentage of 1 wt% (w/w of palm oil). The effects of methanol–palm oil molar ratio, palm oil–microalgae weight ratio, and temperature on biodiesel yield were investigated. The results showed that the best biodiesel yield was 85.28% (99.01% of partial biodiesel yield from palm oil and 16.69% of partial biodiesel yield from dry microalgae), obtained at a methanol–palm oil molar ratio of 10:1, a palm oil–microalgae weight ratio of 5:1, and at a temperature of 60°C. Upon comparison, the overall yield increased by 34.59% (37.73% of partial biodiesel yield from palm oil and 13.00% of partial biodiesel yield from dry microalgae) than that of the two-stage (conventional) method. Single-stage simultaneous extraction–transesterification process also reduced the number of unsaturated fatty acid components in biodiesel that will lower the biodiesel quality.

Optimization and techno-economic analysis of biodiesel production from Calophyllum inophyllum oil using heterogeneous nanocatalyst

The present research work is aimed at reducing the consumption of reactants by process optimization and economic analysis of large-scale commercial plant using techno-economic analysis. The statistical optimization of biodiesel production from Calophyllum inophyllum oil using Zn doped CaO nanocatalyst was used to optimize the conversion efficiency and green chemistry value. The environmental studies on transesterification reaction were done using green chemistry parameters like carbon efficiency, atom economy, reaction mass efficiency, stoichiometric factor and environmental factor. The biodiesel conversion 91.95% was achieved when maintaining the methanol to oil ratio 9.66:1, concentration of catalyst 5% (w/v), time 81.31 min and temperature 56.71 °C with green chemistry value of 0.873. Techno-economic analysis of biodiesel production from Calophyllum inophyllum oil was executed used optimized lab-scale data. The techno-economic analysis of 21 million kg/year biodiesel production plant was investigated. The annual biodiesel revenue of 15,224,000 $/yr and the payback period was about 1.15 years.

Green synthesis of sulfonated organosilane functionalized multiwalled carbon nanotubes and its catalytic activity for one-pot conversion of high free fatty acid seed oil to biodiesel

An environmentally friendly surface modification method was applied to synthesize solid acid catalyst suitable for biodiesel production. The catalyst was prepared from multiwalled carbon nanotube (MWCNT) and 3-mercaptopropyltrimethoxysilane (3-MPTMS) oxidized in hydrogen peroxide under supercritical carbon dioxide (scCO2). The carbon dioxide under supercritical condition with ethanol as cosolvent allows swift transportation and promotes uniform distribution of organosilane groups on randomly entangled and layered orientation of MWCNT. The catalyst was characterized by using Field emission scanning electron microscopy–energy dispersive x-ray (FESEM-EDX), Thermogravimetric analysis (TGA), Fourier transform infrared (FTIR) spectroscopy, X-ray powder diffraction (XRD), Brunauer–Emmett-Teller (BET) analysis and Time-of-Flight secondary ion mass spectrometry (TOF-SIMS). The catalytic activity of the catalyst was tested using a high free fatty acid (FFA)-containing Hibiscus cannabinus (kenaf) oil, and the fatty acid methyl esters (FAME) products from simultaneous esterification and transesterification reactions were quantified. To compare with scCO2 method, an acid catalyst was also prepared using liquid chemical deposition that resulted in only 45.11% biodiesel conversion. On the other hand, the optimum conversion of 93.10% was obtained using a scCO2 synthesized catalyst at the following transesterification conditions: temperature = 63 °C, methanol:oil ratio = 14:1, 10 wt % catalyst and time = 240 min.

Two-step Biodiesel Production from Used Activated Bleaching Earth at Palm Oil Refining Plant

A study on two-step biodiesel production of agricultural by-products, namely palm oil derived using activated bleaching earth )UABE), collected from the Oleen Palm Oil industrial refining plant consisting of 22.4 % of waste oil. This waste oil showed free fatty acid content and a saponification value of 15.5 % and 199.7 mg KOH/g, respectively. The FFA content after esterification should be approximately 1.0%, not only to save glycerol and the catalyst involved in the esterification but also to achieve high biodiesel conversion during the transesterification. An alkaline catalyst was successfully used to produce biodiesel in the second step. A 97.6% conversion to biodiesel based on the European Standard EN 14214:2003 was achieved under the conditions (1.0% NaOH catalyst relative to waste oil, the molar ratio of free fatty acid, and methanol of 1:13.22, 60ºC, 1h). Overall, this novel two-step process achieved highly enhanced biodiesel conversion (74.6% to 100.0%) with a significantly increased molar ratio of free fatty acid and methanol (1:2.71 to 1:15.89) and catalyst requirements (1.0% NaOH).

“Characterization of Biodiesels Produced using Mixed Base Catalyst by Gas Chromatography & FTIR Spetroscopy”

In this study, fish oil & cottonseed oils were used to produce their individual methyl esters using a mixed base catalyst (Sodium hydroxide & di-sodium phosphate). The produced biodiesels were characterized to check the quality of biodiesel and to establish the feasibility of using the mixed base catalyst for production of biodiesels. The biodiesel was characterized by FTIR (Fourier Transform infrared spectrometry) and GC (Gas Chromatography) tests and the other important properties of biodiesel were found out and compared with that of diesel. FTIR test confirms complete conversion of biodiesel from individual oils and the fuel properties were found to be within the range prescribed in ASTM standards. GC analysis has shown presence of more unsaturated fatty acids in cottonseed oil and less in fish oil biodiesel throwing some light on the stability of the fuels. The present characterization studies has established the potential use of mixed base catalyst during transesterification reactions.

Preparation of biochar catalyst from black liquor by spray drying and fluidized bed carbonation for biodiesel synthesis

Lab-scale experiments were carried out to investigate a new approach of preparing biochar-based catalyst for transesterification reaction. Black liquor (BL) from cotton pulping process was used as a precursor for preparing the catalyst via spray drying followed by fast carbonization in a fluidized bed reactor. Response surface methodology (RSM) was employed to statistically analyze and optimize the entire process of catalytic synthesis of biodiesel from a waste frying oil, consisted of the catalyst preparation and transesterification steps. Several major operation parameters of the biodiesel synthesis process, including alkaline loading in biochar, methanol to oil ratio, catalyst loading, and the carbonization temperature of catalyst, were studied for their effects on biodiesel conversion. The optimal condition for achieving the maximum biodiesel conversion (i.e. 91.5 %) was found to be: 27wt% alkaline loading in biochar, 600°C carbonization temperature, 7.7 methanol to oil ratio, and 6.5wt% catalyst loading. Overall, the spry drying fluidized bed carbonization demonstrated its viability for significantly reducing duration of high temperature carbonization, opening up the prospects of manufacturing the catalyst in a much less energy consumption manor.

Ultrasound-assisted production of biodiesel using engineered methanol tolerant Proteus vulgaris lipase immobilized on functionalized polysulfone beads

In the present study, Proteus vulgaris lipase (PVL) was engineered using directed evolution to increase methanol tolerance so that it would be more tolerant and efficient for harsh conditions employed in biodiesel synthesis, which is limiting their industrial use. The influence of ultrasound under different experimental conditions on the biodiesel conversion yield using methanolysis of non-edible neem oil was also emphasized. A special attention was also paid to the immobilization of lipase on Polysulfone (PS) beads and comparative studies with industrially used Burkholderia cepacia lipase. The Engineered Proteus vulgaris lipase showed >80% activity after 3 h when incubated in 50% methanol with simultaneous sonication. The lipase retained improved longevity (~70% residual activity) over wild-type PVL over repeated use.

Synthesis, characterization and biodiesel conversion of monodispersed sulfonated-silica nanoparticles

The enhancing need of energy followed by increasing of human population to be main factors in fuels depleting. This motivated researcher over the world to solve and to utilize natural resources as bioenergy for human sustainability in future. Today, there are numerous research related to bioconversion and bioprocessing of natural resources as well as optimizing catalyst in biodiesel conversion. Design of suitable catalyst for biodiesel conversion to be a challenge in this research area. In this paper, we report of preparation, characterization and biodiesel conversion ability of heterogeneous catalyst, so called monodispersion sulfonated-silica nanoparticles (MSN). This nanoparticles was characterized by FTIR, TEM, SEM and SEM-EDAX as well as N2 adsorption-desorption. The result revealed that the catalyst prepared through CTAB templating technique has been successfully synthesized with high monodispersion nano-size. Moreover, its ability in biodiesel conversion up to 13.33% for purity percentage.

Numerical Simulation of Biodiesel Synthesis in T- Channel Microreactor

Biodiesel promising as an alternative to the diesel. The transesterification reaction process involved the reaction of triglyceride with alcohol in the presence of catalyst. In the research, the Computational Fluid Dynamic (CFD) method was used to simulate the transesterification reaction process. The inlet pressure range from 0.0001 Pa to 0.01 Pa, temperature of 25°C, 50°C, 75°C and the molar ratio at 6:1, 9:1 were used to investigate their effect of toward the biodiesel conversion. Finding shows that high conversion of biodiesel occurred at low inlet pressure of 0.001 Pa with temperature of 50°C and the ethanol to oil molar ratio at 9:1.

Performance, Emission and Combustion Characteristics of a Diesel Engine Powered by Macadamia and Grapeseed Biodiesels

Biodiesel is an alternative, eco-friendly and renewable source of energy. It can be produced from a wide range of feedstocks which can be grown in marginal land use. It has drawn more attention to the researchers. In this study, the oil extraction, biodiesel conversion, and physiochemical properties of Macadamia (Macadamia integrifolia) and Grapeseed (Vitis vinifera) biodiesels are presented. The experimental investigation of diesel engine performance, emissions and combustion characteristics were conducted using B5 (5% biodiesel and 95% diesel by volume) and B10 (10% biodiesel and 90% diesel by volume) blends. The engine performance parameters, such as brake power (BP), brake specific fuel consumption (BSFC), and brake thermal efficiency (BTE) have been investigated in this experiment. The emission parameters, for example, carbon monoxide (CO), the ratio of CO2/CO, nitrogen oxide (NOx), hydrocarbon (HC), particulate matter (PM) have been measured during the experiment. Finally, the combustion parameters such as cylinder pressure (CP) were recorded, and heat release rate (HRR) was analysed and compared with that of diesel fuel. The study revealed that the Macadamia biodiesel performed better than Grapeseed biodiesel and behaved closely to that of diesel fuel. A significant reduction of engine emissions was found in the case of Macadamia biodiesel with a minimal reduction of engine performance. Further analysis of energy, exergy and tribological characteristics of the Macadamia biodiesel is recommended for assessing its feasibility for commercial application.

African oil bean seed as feedstock for bio-oil and biodiesel production and on the effects of thermal pre-treatments on the quality of the bio-oil

This research is on the introduction and the effect of the pre-treatment method on oil recovery from African oil bean seeds for biodiesel production. Samples were dried in the solar dryer, open sun, and the oven at 50 °C, 60 °C, and 70 °C. The solvent extraction process with hexane was used to extract oil from the product, and their saponification value, peroxide value, acid value, iodine value, specific gravity, and the color of the bio-oil were analyzed. The oil was further used in acid-catalyzed esterification and alkaline transesterification for biodiesel production, and the effects of temperature, catalyst concentration, feedstock to methanol molar ratio, and reaction time on biodiesel conversion were investigated. Solar drying of the seed yielded the highest volume of oil compared with other drying methods. Peroxide values of the oil meet the standard values from CODEX but showed an increase in rancidity in the solar-dried and open sundried products. Bio-oil produced has good lubricating properties as its iodine properties showed that it is not a drying oil. The cetane number and heating value of the biodiesel produced are within the range when compared with the ASTM standard of diesel properties. By using a feedstock to methanol molar ratio of 1:6 and a sulfuric acid concentration of 0.8%, a biodiesel conversion of 81% was obtained after 6 h of reaction at 60 °C. The biodiesel produced by this process met the American Society for Testing and Materials (ASTM) standard.

Pineapple (Ananás comosus) leaves ash as a solid base catalyst for biodiesel synthesis

Homogeneous catalysts used for biodiesel synthesis have several limitations, including non-recoverability/reusability, saponification, emulsification, equipment corrosion, and environmental pollution. To overcome these limitations, we synthesized a novel catalyst via calcination of pineapple leaves waste. This catalyst was characterized by X-ray powder diffraction, X-ray fluorescence, Fourier transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, and soluble alkalinity measurements. The catalyst’s activity with regards to soybean oil transesterification was analyzed, and multiple process parameters (temperature, catalyst amount, reaction time, and methanol:oil molar ratio) were examined. A high catalytic activity, probably related to the 85 wt% content of alkali/alkali metals (K, Ca and Mg), was observed after a 30 min reaction time, 60 °C, 4 wt% of catalyst, oil to methanol molar ratio of 1:40, reaching an oil to biodiesel conversion above 98%. We conclude that the novel catalyst presented here is efficient, cost-effective, and sustainable, while simultaneously abundant waste is reduced.

Application of Condenser for Methanol Recovery in Biodiesel Setup

The waste cooking oil is transfered into biodiesel by using potassium hydroxide (KOH), alcohol (methanol) at a set temperature and time. The concentration of catalyst should be at correct level or else it will lead to negative effect on the overall output of the biodiesel produced. The biodiesel conversion is done to remove the free fatty acids present in the vegetable oil using transesterification process. It is known that the boiling point of methanol is 67 °C it gets evaporated if the reaction temperature exceeds beyond the boiling point. Due to evaporation the methanol required for the reaction to proceed forward may not available. Thus inorder the save lose of methanol due to evaporation during high temperature operations, a condenser is required to condense the escaping methanol in the form vapour. This condensed methanol is again sent back to the reaction vessel to carry the transesterification reaction. Petroleum diesel is widely used in the automobile sectors, industry purpose, domestic uses and in agriculture for generation of power (mechanical) energy for the purpose of meeting the energy demands. The fuels from alternate sources are renewable and does not cause severe effect on the environment. Biodiesel is one such source of fuel which can greatly support to reduce the dependency on conventional fuels. It will complete process in 1 to 2 days to finish the vegetable oil into biodiesel fuel. Biodiesel is renewable energy source to be produce the natural oil and also fats. Hence producing biodiesel is will be a better way to compensate the energy demands and the cost involved during production should also be considered. One of the cost reducing method is saving the raw materials from wastage.

Resource Recovery from Waste Coffee Grounds Using Ultrasonic-Assisted Technology for Bioenergy Production

Biodiesel is a proven alternative fuel that can serve as a substitute for petroleum diesel due to its renewability, non-toxicity, sulphur-free nature and superior lubricity. Waste-based non-edible oils are studied as potential biodiesel feedstocks owing to the focus on the valorisation of waste products. Instead of being treated as municipal waste, waste coffee grounds (WCG) can be utilised for oil extraction, thereby recovering an energy source in the form of biodiesel. This study evaluates oil extraction from WCG using ultrasonic and Soxhlet techniques, followed by biodiesel conversion using an ultrasonic-assisted transesterification process. It was found that n-hexane was the most effective solvent for the oil extraction process and ultrasonic-assisted technology offers a 13.5% higher yield compared to the conventional Soxhlet extraction process. Solid-to-solvent ratio and extraction time of the oil extraction process from the dried waste coffee grounds (DWCG) after the brewing process was optimised using the response surface methodology (RSM). The results showed that predicted yield of 17.75 wt. % of coffee oil can be obtained using 1:30 w/v of the mass ratio of DWCG-ton-hexane and 34 min of extraction time when 32% amplitude was used. The model was verified by the experiment where 17.23 wt. % yield of coffee oil was achieved when the extraction process was carried out under optimal conditions. The infrared absorption spectrum analysis of WCG oil determined suitable functional groups for biodiesel conversion which was further treated using an ultrasonic-assisted transesterification process to successfully convert to biodiesel.

Transesterification of triglyceride over Ni impregnated Zn/CaO nanocatalysts

A series of Ni loaded Zn/CaO mixed oxides were prepared by wet impregnation process and their catalytic activities were investigated for transesterification of triglyceride. The physico-chemical properties of the catalysts were characterized by powder XRD, SEM, TEM, FT-NMR and temperature programmed desorption (TPD) studies. The prepared catalyst was successfully employed for the transesterification of waste cottonseed oil (WCO) having 4.4 wt% of free fatty acid contents. The catalytic amount of 5 wt% Ni/Zn/CaO catalyst (with respect to WCO), shown higher conversion (∼98%) of biodiesel compared to other wt% of catalysts. The catalyst was recovered from the reaction mixture by simple filtration and reused for three consecutive runs.

Biodiesel synthesized from waste cooking oil in a continuous microwave assisted reactor reduced PM and NOx emissions

A synergistic effect of the activated limestone-based catalyst (LBC) and microwave irradiation on the transesterification of waste cooking oil (WCO) was screened using a two-level factorial design and response surface methodology. The catalyst was prepared using a wet-impregnation method and was characterised for its surface element, surface morphology, surface area and porosity. The reaction was performed in a purpose-built continuous microwave assisted reactor (CMAR), while the conversion and yield of biodiesel were measured using a gas chromatography. The results showed that the catalyst loading, methanol to oil molar ratio and the reaction time significantly affect the WCO conversion. The optimum conversion of oil to biodiesel up to 96.65% was achieved at catalyst loading of 5.47 wt%, methanol to oil molar ratio of 12.21:1 and the reaction time of 55.26 min. The application of CMAR in this work reduced the transesterification time by about 77% compared to the reaction time needed for a conventional reactor. The biodiesel produced in this work met the specification of American Society for Testing and Materials (ASTM D6751). Engine test results shows the biodiesel has a lower NOx and particulate matters emissions compared to petrodiesel.

Effect of Catalysts on the Quality of Biodiesel from Waste Cooking Oil by Induction Heating

The target of increasing the use of renewable fuels is directly proportional to the increasing demand for biodiesel. High demand for biodiesel must be balanced with sufficient availability from producers. One of the factors that influence biodiesel conversion rate is the use of catalysts. The use of sodium teoxide (CH3ONa) catalyst in the manufacture of biodiesel can be applied in the process of biodiesel production using induction heating technology. This technology will accelerate the heating process needed in the transesterification reaction. Based on research that has been done, the use of a catalyst concentration of 1% will produce a yield of 86.95% with product quality in accordance with SNI such as density 0.858 gr/cm3, viscosity 5.727 cSt, flash point 190°C, and acid number 0.439 mg-KOH/gr.

Efficient production of biodiesel by using a highly active calcium oxide prepared in presence of pectin as heterogeneous catalyst

The cation binding ability of pectin was explored for the preparation of a highly active CaO catalyst for soybean oil transesterification. The catalyst was prepared by the precipitation method using Na2CO3 and Ca(NO3)2 in the presence of pectin followed by calcination. The best catalyst, CaP-600, was prepared at 600 °C and was characterized by FTIR, TGA, BET, CO2-TPD and powder X-ray diffraction (PXRD). CaP-600 was characterized as CaO containing carbonaceous materials left from pectin combustion. At only 1 wt% CaP-600 loading, biodiesel conversion reaches 99% after 4 h with a methanol:oil = 7:1 M ratio. Importantly, the calcium content in the produced biodiesel was only 0.7 ppm, which implies a satisfactory compliance with the ASTM D6751 and EN 14,214 standards. To the best of our knowledge, this is the best CaO catalyst reported for biodiesel production in terms of efficiency and amount of calcium leached. For comparison, CaO prepared in the absence of pectin showed poor catalytic activity in the optimized reaction conditions, demonstrating that the presence of the biopolymer prior to the calcination step is crucial for the catalytic performance of the CaO particles. Possible rationales for the biopolymer role are discussed.