Stability Of Biodiesel Research Articles

Effect of synthetic and aromatic amine antioxidants on oxidation stability, performance, and emission analysis of waste cooking oil biodiesel.

In the present study, an attempt was made to improve the oxidation stability of biodiesel by adding antioxidants to waste cooking oil biodiesel, and their impact on performance and emissions was analyzed. Two types of antioxidants were chosen for the analysis: an aromatic amine antioxidant, diphenylamine (DPA), and synthetic oxidants, tert-butylhydroxyquinone (TBHQ) and pyrogallol (PY). All the antioxidants were added to the biodiesel at doses of 200ppm and 500ppm to evaluate their effect. The oxidation stability was found as per the ASTM standard by mixing 500ppm antioxidants for all three antioxidant-treated biodiesel blends. DPA yielded similar results as TBHQ, although PY had a better oxidation stability according to the Rancimat test. Gas chromatography and mass chromatography were also performed on the neat biodiesel. Performance and emission tests were performed on the antioxidant-treated biodiesel blends and diesel. The brake thermal efficiency of the tested fuel increased by 9.8%, 6.9%, and 15.88% when the DPA, TBHQ, and PY antioxidants were added to the test fuel compared to that of the test fuel without added antioxidant. The brake specific energy consumption of the test fuel decreased by 9.05% with DPA, 7.03% with TBHQ, and 14.08% with PY compared to that of the test fuel without antioxidant. The NOx emissions of the antioxidant-treated test fuels were reduced by 14.65% with DPA, 11.22% with TBHQ, and 23.10% with PY compared to those of the test fuel without antioxidants. Additionally, the aromatic amine antioxidant (DPA) was found to be effective in enhancing the performance and lowering the exhaust emissions compared to diesel for unmodified diesel engines.

Oxidation stability and cold flow properties of biodiesel synthesized from castor oil: Influence of alkaline catalysts type and purification techniques

This study investigates the effects of catalyst type and washing procedures on the oxidation stability and cold flow parameters of biodiesel produced from castor oil. Castor oil was synthesized using two different catalysts; calcium oxide on alumina support (CaO-Al2O3) and potassium hydroxide (KOH) at a temperature of 60˚C, methanol to oil molar ratio of 6:1 and catalyst loading of 1 wt% of oil for 60 min. The resulting biodiesel was purified using water washing and dry washing methods ion exchange resin. The oxidation stability and cold flow behaviour of the biodiesel produced (cloud point, pour point, cold filter plugging point, and low-temperature flow test) were determined. The findings showed that the oxidation stability and cold flow properties of biodiesel is independent of washing methods but varies with catalyst type. The heterogeneously catalyzed transesterification by CaO-Al2O3 exhibited higher oxidation stability with an induction period of 4.4 h as against 3.5 h for the potassium hydroxide (KOH) catalyzed biodiesel. However, the values obtained in this study were above the ASTM standard of 3 h minimum. With regards to cold flow properties, the KOH-catalyzed process exhibited better cold flow properties than CaO-Al2O3 catalyzed biodiesel. It can be deduced from this study that the biodiesel samples will exhibit very good ignition performances when used in ignition compression engines in the low temperate region due to their satisfactory cold flow behaviour.

INFLUENCE OF STORAGE PERIOD ON THE THERMAL AND OXIDATION STABILITY OF JATROPHA BIODIESEL AND ITS BLENDS

INFLUENCE OF STORAGE PERIOD ON THE THERMAL AND OXIDATION STABILITY OF JATROPHA BIODIESEL AND ITS BLENDS

Influence of nano-additives on engine behaviour using diesel-biodiesel blend

Biodiesel, a potential liquid alternative fuel, offers an excellent property such as extend the longevity and clean burning fuel and reduces the greenhouse gas emissions since the trees planed for feedstock of biodiesel absorbs. It also helps to reduce dependency on fossil fuel and helps to economy. Biodiesel offers numerous advantages over conventional diesel, but it has some issues such as its high viscosity, poor cold flow properties, higher nitric oxide (NOx) emissions and poor oxidation stability. Although there are many methods in order to overcome this drawback, addition of nanoparticles in biodiesel has emerged as one of the potential solutions. The nanoparticles improve the thermochemical properties of the fuel. Some studies have been carried out on nano-sized particles in diesel–biodiesel fuel emulsions. The current paper discusses about the effect of nano particles on engines performance and emission parameters and engine life. The paper also discusses about the effect of different size and dosage of nano particles on diesel engine behaviour. The preparation of nanofluid, several characterization methods and enhancing the stability of biodiesel via various techniques are also presented in this paper.

Application of Orange Peel Extract (Op) as Antioxidant Additive for Enhancing Oxidation Stability of Biodiesel

Application of Orange Peel Extract (Op) as Antioxidant Additive for Enhancing Oxidation Stability of Biodiesel

Assessment of Oxidative Stability of Biodiesel and Biodiesel Blends

Assessment of Oxidative Stability of Biodiesel and Biodiesel Blends

Enhancing the Oxidation Stability of Biodiesel by a Novel Ionic Liquid Antioxidant: [Uim0y2][C6h2(Oh)3coo

Enhancing the Oxidation Stability of Biodiesel by a Novel Ionic Liquid Antioxidant: [Uim0y2][C6h2(Oh)3coo

Liposome nanocapsules of aqueous extract from defatted wheat germ as by-products to enhance stability of biodiesel

Liposome nanocapsules of aqueous extract from defatted wheat germ as by-products to enhance stability of biodiesel

Oxidative stability of biodiesel: recent insights

AbstractBiodiesel, the fatty acid methyl ester (FAME) of vegetable and animal oil, is now used extensively worldwide, with blends of up to 7% common. The blending level is still somewhat limited due to a perceived susceptibility of these fuels to oxidation. Oxidation follows a number of pathways, with the primary mechanism being auto‐oxidation, a radical process that results in the production of a range of oxygenated components. These eventually increase the viscosity of the fuel and form deposits detrimental to operation. Further fuel properties are also heavily reliant on the level of oxidation. As such, one of the main challenges in the use of biodiesel is its long‐term instability when stored. Typically synthetic anti‐oxidants have been used to address this issue; however, these systems can also add to the formation of deposits, as well as hazardous emissions, on combustion. Recently, research has focused on novel antioxidant development mainly from plant extracts, although there are a number of other routes for improved performance, including the commercialization of hydrogenated vegetable oil (HVO), a prominent alternative to FAME‐based biodiesel due to its higher stability, straight chain paraffin composition, and better cold flow properties. In this review, the factors that promote this oxidation are presented, including molecular composition, metal contamination, temperature and light exposure, as well as the latest findings on the inclusion of HVO, the current state‐of‐the‐art analytical techniques employed, and the impact of higher pressure injection systems on vehicles that demonstrate deposit formation is not solely due to the unsaturated biodiesel components. © 2021 Society of Chemical Industry and John Wiley & Sons, Ltd

A renewable lignin-derived bio-oil for boosting the oxidation stability of biodiesel

The valorisation of lignin is being increasingly recognised to improve the economics of pulp and paper making mills. In the present study, an integrated lignin–glycerol valorisation strategy is introduced with an overarching aim for enhancing the process value chains. LignoBoost kraft lignin was subjected to base-catalysed depolymerisation using glycerol as a co-solvent. The generated bio-oil was used as a renewable additive to biodiesel for enhancing its oxygen stability. The influence of three independent parameters including temperature, time and glycerol amount on lignin depolymerisation was investigated. Response surface methodology was applied to design the experiments and to optimise the process for maximising the yield and antioxidant impact of bio-oil. The results showed that glycerol has a positive qualitative and quantitative impact on the produced bio-oil, where an enhancement in the yield (up to 23.8%) and antioxidant activity (up to 99 min induction period) were achieved using the PetroOxy method (EN16091). The addition of 1 wt% bio-oil to biodiesel has led to an improvement in the oxidation stability over a neat sample of up to ∼340%, making it compliant with European standard (EN14214). The proposed process presents a biorefinery paradigm for the integrated utilisation of waste cooking oil, lignin and glycerol.

Potential application of supercritical extract of pomegranate peel as bio‐antioxidant for biodiesel

AbstractThe performance of the pomegranate peel extract against the synthetic antioxidant additives on the oxidation stability of commercial biodiesel B100 derived from soybean was evaluated. The experimental extraction was conducted under 200 bar, 35, 45, and 55°C, and 0.0, 2.5, and 5.0 mL of ethanol as co‐solvent. Due to the rich in squalene and α‐tocopherol composition, all extracts presented high antioxidant capacity, 16.70 to 1.68 μg mL−1. In the oxidation stability tests, the addition of 1000 ppm of the supercritical extracts of pomegranate peel to biodiesel resulted in the increment of the induction time of pure biodiesel by up to 1.83. In contrast, the biodiesel added at 1000 ppm with commercial antioxidants increased the times up to 1.58 and 1.79, respectively for butylated hydroxyanisole and butylated hydroxytoluene. Biodiesel added with supercritical extract of pomegranate peel, obtained under 35°C and with 5.0 mL of ethanol, presented higher efficiency in the prevention of the oxidative process and was in accordance with norm European Standard EN 14214. The findings revealed that the extract is a promising natural antioxidant for biodiesel, that, besides being eco‐friendly, is an additive that can substitute commercial synthetic antioxidants, extending biodiesel stability.

Evolution of 307 L Stainless Steel Corrosion on the Oxidative Stability of Biodiesel During Storage

Evolution of 307 L Stainless Steel Corrosion on the Oxidative Stability of Biodiesel During Storage

The effect of tetrethylenepentamine (TEPA) on the oxidation stability and the lubrication performance of biodiesel

The oxidation stability and lubrication properties of biodiesel have been the focus of research, this study focuses on the oxidation and lubrication properties of TEPA on biodiesel and its anti-oxidation and lubrication mechanisms. The Rancimat method was used to study the oxidation resistance of TEPA. The results showed that when 3‰ of trace TEPA was added, the oxidation performance of Jatropha biodiesel was improved by 11.41 times, and the stability factor of TEPA's antioxidant activity is greater than 1 under micro conditions, and the oxidation resistance was significantly improved. The kinetic parameters and thermodynamics of the oxidation degradation process of TEPA were analyzed. The results showed that the kinetic activation energy was 86.756 kJ mol−1, the reaction order was 1, the frequency factor A is 1.235 × 1011, the thermodynamic activation entropy was −43.059 J mol−1 K−1, by the results shown, the existence of an endothermic and non-spontaneous process and the antioxidant product of TEPA was a good free radical inhibitor. The High Frequency Reciprocating Rig (HFRR) was used to study the lubricating performance of TEPA for Jatropha biodiesel at different temperatures (40 ℃–80 ℃) and different adding amount (0–2.5 wt.%). The average friction coefficient of Jatropha biodiesel with the addition of 2.5‰ TEPA decreased by 88.89 % (at 40 ℃), and the lubrication performance was greatly improved, However, the increase in temperature will have a greater impact on the lubrication improvement effect of TEPA. When the experimental temperature is, 50 ℃, 60 ℃, 70 ℃, 80 ℃, the average friction coefficient when adding 2.5‰ TEPA decreases respectively. 81.82 %, 76.92 %, 57.14 %, 52.94 %, the lubrication improving effect of Jatropha biodiesel gradually decreases. The high viscosity characteristics of TEPA and the ability to chelate metal ions in biodiesel are the main reasons for improving the lubricating performance of biodiesel.

Physicochemical Properties Enhancement of Biodiesel Synthesis from Various Feedstocks of Waste/Residential Vegetable Oils and Palm Oil

The main aim of the present study was to improve the oxidation stability and cold flow properties of biodiesel produced from waste frying/cooking oil and palm oil. In this work, waste frying/cooking methyl ester (WFME) and palm methyl ester (PME) were prepared using an alkali-catalyzed transesterification process, and the physicochemical properties of the pure biodiesel as well as of binary blends among them were investigated. The results indicated that palm biodiesel and WFME18, produced from a mixture of frying, cooking, sunflower, and corn oils, can be used as antioxidant additives, enhancing biodiesel stability. Additionally, it was found that WFME1 and WFME12 derived from waste residential canola oil can be used as cold flow improvers for enhancing the cold flow properties of palm biodiesel. Moreover, ultra-low sulfur diesel fuel winter (ULSDFW), ultra-low sulfur diesel fuel summer (ULSDFS), kerosene (KF), and benzene (BF) were utilized to enhance the cold flow properties of the samples and meet the requirements of diesel fuel standards. The investigation of the experimental results indicated that blending WFME-PM with a low proportion of petroleum-based fuel (KF and BF) could significantly improve the cold flow properties (CP and PP) as well as oxidation stability of WFME.

SURFAKTAN UNTUK BAHAN BAKAR SOLAR DAN BIODIESEL

The government has determined that Indonesia is gradually implementing biodiesel as a substitute for fossil fuels. In September 2018 the B20 rule was established, then B30, and by the end of 2020 it became B50. That means 20%, 30%, and 50% of fuel is biodiesel. Fatty acid methyl ester (FAME) known as biodiesel which is synthesized from palm oil produces a high yield, up to 95%. However, in practice mixing FAME and diesel oil still has obstacles such as FAME will separate from diesel and form a gel, this is due to the hygroscopic nature of FAME and higher density of FAME compared to diesel oil. The decline in the quality of biodiesel is also caused by changes in some chemical and physical characteristics during storage. To overcome these problems, an emulsifier or surfactant solution is needed to homogenize the mixture of diesel fuel and biodiesel. Surfactants in biodiesel not only function as emulsifiers but also provide other added values, such as reducing hydrocarbons, CO, CO2, and NOx in exhaust gas emissions when compared to without surfactants. Some literature suggests that 35% reduction in hydrocarbon emissions occurs when Jatropha methyl ester has been mixed with surfactant and nano carbon compared to Jatropha methyl ester alone. The use of nano additives also showed differences in the stability of biodiesel and surfactants, the addition of nano additives in the form of nano carbon and nano cerium increased the stability and homogeneity of biodiesel for longer. Thus, biodiesel can be stable for a certain period of time. This review will show the various types of emulsifiers used in fuel mixing and the time of stability formed.Keywords: biodiesel, emulsifer, homogenization, palm oil, diesel fuel

Effects of unsaturated fatty acid methyl esters on the oxidation stability of biodiesel determined by gas chromatography-mass spectrometry and information entropy methods

To explore the trend of fatty acid methyl esters (FAMEs) during the oxidation process of biodiesel, this study uses gas chromatography - mass spectrometry (GC-MS) combined with information entropy theory to propose a new method to analyze the effect of FAMEs on the stability of biodiesel (especially with different amounts of unsaturated FAMEs). The induction periods of the main FAMEs in biodiesel were determined by the Rancimat method. The results showed that the longest induction period of methyl stearate was 248 h, while the induction of methyl linoleate was only 0.12 h. Accelerated oxidation of biodiesel, using GC-MS analysis showed that the oxidation trends of FAMEs was different. The oxidation rate of methyl linoleate was the fastest. A mathematical equation was proposed to calculate the trend of FAMEs. The results showed that during the 5 h accelerated an oxidation process, the content of methyl linoleate decreased from 28.35% to 2.10%, while the content of methyl oleate decreased by 18.21%. Using information entropy, the weighting coefficients of FAMEs in the oxidation process of biodiesel were calculated. The weighting coefficient of methyl linoleate was as high as 0.6797. Methyl linoleate was the main reason why biodiesel was easily oxidized.

Study of light wavelength on the oxidative stability of Jatropha biodiesel

The oxidative stability of Jatropha biodiesel after exposure to different wavelengths of visible light was studied and kinetic analysis of the oxidation process was carried out. The results showed that the induction period of Jatropha biodiesel was 5.12 h and visible light at different wavelengths affected the oxidation of biodiesel differently. Effect of oxidation was the strongest in the purple, where the induction period was reduced to 2.65 h. The red had the weakest effect on biodiesel oxidation, and the induction period was reduced to 4.61 h. Acid value detection, component analysis and UV characterization of biodiesel oxidized by visible light at different wavelengths. The results showed that with the decrease of light wavelength, the acid value of the biodiesel increased from 0.2577 mg KOH/g to 0.3438 mg KOH/g and the content of methyl linoleate containing two carbon–carbon double bonds decreases. UV characterization results showed that the absorption peak absorbance of conjugated double bond of Jatropha biodiesel oxidized by purple light was 5.282, while the absorption peak absorbance of conjugated double bond of Jatropha biodiesel oxidized by red light was only 2.877, and purple light was helpful to stimulate the generation of conjugate double bond. The kinetic analysis results showed that the different wavelengths had different rates of biodiesel degradation. Purple light has the fastest oxidation rate. The oxidation rate constant k1 was 0.06011, the reaction order was n = 1, and the minimum activation energy of the oxidation reaction process was 19.79 kJ·mol−1.

Techniques to improve the stability of biodiesel: a review

Biodiesel is an alternative to fossil fuels for diesel engines, yet actual biofuel properties need to be tuned to comply with fuel standards. In particular, fuel stability is required for efficiency and commercial use. Fuel stability varies with the nature and proportion of chemical functional groups of biodiesel. Optimum oxidation stability is required because degradation by oxidation gives products that compromise fuel properties and impair fuel quality and engine performance. For instance, oxidation induces the formation of short-chain corrosive acids and deposits. Here, we review techniques to improve the oxidation stability of biodiesel. For instance, stability is improved by additives such as antioxidants. Factors influencing oxidation stability include composition of fatty acids, acid content, peroxide content, iodine content, viscosity, insoluble impurities, external conditions, and storage material. Antioxidants reduce lipid peroxidation at the beginning of the chain reaction and increase the onset temperatures.

Investigation of the shelf life of the optimized Neem biodiesel and its execution and excretion characteristics on automotive diesel engine

ABSTRACT The national biofuel policy of the Indian government support to put a great emphasis on the synthesis of biodiesel from the nonedible feedstock. A potential option in this regard is Neem oil which is found in abundance in India (~1,00,000 tonnes). The major hindrance to the commercialization of biodiesel is its shelf life due to poor oxidation and stability characteristics. The current work investigates the oxidation stability of Neem biodiesel as per EU standard (EN14214) using the Rancimat apparatus. The oxidation stability of 12.3 hours without doping any chemical antioxidant in the synthesized Neem biodiesel makes it highly suitable for commercial acceptance. The impact of pyrogallol (PY) antioxidant was also investigated on the shelf life of Neem biodiesel build on response surface methodology (RSM) in accordance with Box-Behnken Design (BBD). Moreover, the execution and excretion characteristic of the Neem biodiesel blends: B15, B25, B35, and B45 are investigated on direct injection automotive compression ignition engine. Based on this broad experimental investigation B15 blend can be used as a fuel to power the existing automotive compression ignition engine with no compromise in the execution and excretion characteristics of the engine. From the analysis of the data of life-cycle assessment of the Neem biodiesel, it was found that it possesses the global warming potential of 45.72gCO2-eq Functional Unit−1 which is six times lesser than mineral diesel. Moreover, the Neem plantation has a carbon dioxide isolation potential of around 10 t ha−1 year −1. All these factors make the Neem Biodiesel highly suitable for blending with mineral diesel to power the existing compression ignition engines.

Effect Soursop Leaf Extract For Oxidation Stability Of Palm Oil Biodiesel and Soybean Oil Biodiesel

Biodiesel is one of the alternative energy sources for diesel oil substitutes. However, the unsaturated fatty acid contains in vegetable oils leads to the poor oxidation stability of biodiesel. One of the potential methods used to prevent or delay the oxidation reaction is the addition of antioxidants because the process is much more straightforward and efficient. Soursop leaf was reported to have the potential to be used as a natural antioxidant. Soursop leaf extracted using solvent n-hexane and ethyl acetate. The crude extract with concentration 0, 100, 200, 300, 400 ppm tested to palm oil and soybean oil biodiesel. Oxidation stability of biodiesel analyzed using the 873 Rancimat instrument biodiesel. The results show that a concentration of 100 ppm soursop leaf extracted with both n-hexane and ethyl acetate increased the Induction Period (IP) of palm oil biodiesel more than 16 h. This result meets the SNI biodiesel requirements in which the IP minimum for biodiesel is eighth.