Cold Flow Properties Research Articles

Biodiesel Production from Four Residential Waste Frying Oils: Proposing Blends for Improving the Physicochemical Properties of Methyl Biodiesel

The physicochemical properties of biodiesel fuels and their blends prepared from four residential waste vegetable frying oils (sunflower (FSME), canola (FCME), mixture of sunflower and rapeseed (FSRME) and corn (FSCME)) were evaluated and measured to determine the best blend. The results indicate that the stability of 10 biodiesel blends was above 10 h for 0-month, meeting the stability requirement regulated in EN 14214:2014 by adding FSCME, which depends on the concentration amount of FSCME. Besides, the results showed that all fuel samples did not meet the requirements of diesel fuel standards. Therefore, automobile gasoline is used as an additive to unmixed biodiesel in various concentrations to reduce the kinematic viscosity, density and cold flow properties. The results indicate that BG85 and BG80 have met the mixed pure biodiesel with gasoline fulfilled diesel fuel quality standard. Therefore, the samples with stability above 10 h were mixed with gasoline in 15% and 20% to reduce the cold flow properties and meet the specifications of the diesel fuel standards. Moreover, the effect of long-term storage on the properties of all samples was investigated under different storage conditions. The results indicate that higher storage temperatures and longer storage periods negatively influenced the properties of the fuel samples.

Spectral, thermoanalytical characterizations, properties, engine and emission performance of complementary biodiesel-diesel-pentanol/octanol blends

Waste cooking oil (WCO) is a mixture of animal fats and used vegetable oils used at high temperatures. It can be obtained at almost no cost. In this work, valorisation of WCO for biodiesel production (WCOME) besides assessing the quality of its binary and ternary blends with Euro diesel and higher alcohols of pentanol and octanol were examined. WCOME satisfied both EN 14214 and ASTM D6751 standards concerning cetane number (53.9), kinematic viscosity at 40 °C (3.55 mm2/s), density (899.9 kg/m3) at 20 °C and iodine value (106.59 g iodine/100 g). These results are attributed to the excellent degree of unsaturation (110.58). Introducing higher alcohols to biodiesel-diesel blends has further improved their densities and cold flow properties. Furthermore, spectral studies including FT-IR, UV–vis and NMR and thermoanalytical characterizations including TGA and DSC analyses were studied to assess the influence of pentanol and octanol addition into biodiesel-diesel blends. Finally brake thermal efficiency and BSFC and 3 regulated emissions of CO, THC and NOx emissions were evaluated. The current study proved the positive impact of higher alcohols addition to the blends. This study supports the ongoing research on biodiesel synthesis from waste cooking oil in Turkey.

Cold Flow Properties of Biodiesel and the Improvement Methods: A Review

Biodiesel is a mixture of fatty acid alkyl esters (FAAEs) produced by transesterification, which has been promoted as a substitute for petroleum diesel in some areas of China. However, it shows poo...

Optimizing biodiesel production from abundant waste oils through empirical method and grey wolf optimizer

The failure of classical techniques and algorithms have triggered researchers to search for stochastic tools capably of exploring the search space with constant convergence speed. Grey wolf optimizer (GWO) is a moderately novel stochastic algorithm with only a few parameters to regulate that can be easily employed for global optimization. For the first time, this study explored GWO to model biodiesel yield. It is worthy to note that, kerosene (KS) popularly known as paraffin oil has gained global attention in the aviation and biodiesel industries to improve cold flow properties and can be mixed with diesel in different proportions. Therefore, in this study, (1) Response Surface Methodology (RSM) and GWO were explored to model the waste sunflower oil methyl ester (WSOME)/biodiesel (BD) production from waste sunflower oil (WSO) and (2) Least square regression method was accosted to correlate the density of (0%KS + 100%BD), (5PKS + 95%BD), (20%KS + 80% BD), (50%KS + 50%BD) and (100%KS + BD) blends. The yield of WSOME (96.70%) was optimum at the methanol/oil molar ratio of 5.99/1, catalyst amount of 1.1 wt.% and reaction time of 77.6 min. The GWO model displayed a higher coefficient of determination, and a lower value of root mean squared errors compared to the RSM model. GWO predicted values, as compared to RSM, predicted yield indicates its reliability and usefulness for prediction without trial and error of conventional experimentation. The fuel properties concurred with the ranges of the ASTMD6751 and EN 14214 specifications. The quadratic relation with high regression coefficient (R2) was detected for the densities of (0%KS+100%BD) and (20%KS +80% BD) while the linear was found suitable for the densities of (5KS + 95%BD), (50%KS +50BD) and (100%KS+0%BD). The model and correlations can find application in biodiesel and aviation industries.

Various adsorbents to improve the filterability of biodiesel

Cold flow properties are the primary drawback to the common usage of biodiesel as an alternative fuel to diesel. Biodiesel's cold flow behaviour is discovered for the main reasons of presence of precipitant or crystal initiate by minor components such as monoglycerides and steryl glycosides. The ASTM test for this precipitant is ‘The Standard Test Method for Determination of Fuel Filter Blocking Potential of Biodiesel (B100) Blend Stock by Cold Soak Filtration Test (CSFT)’. Therefore, in this study, the performance of commercial activated carbon, silica and beach sand as adsorbent is studied in improving the filterability of two different level of refined biodiesel. The adsorbents were used to treat the biodiesel by removing the impurities present in the biodiesel such as the monoglycerides and steryl glycosides compound from biodiesel using adsorption technique. The efficiency of the adsorbent is determined by performing the cold soak filtration test. Based on the cold soak filtration test, precipitate is not visible and the CSTF is within the 360 s limit for the both refined level of biodiesel. However, treatment of these biodiesel with commercial activated carbon, silica and beach sand resulted in further reduce in CSFT. Commercial activated carbon found to be the most effective adsorbent, followed by silica. This is because both adsorbents possessed high surface area of 657.0420 m2/g and 320.2724 m2/g respectively and high pore volume of 0.379097 cm3/g and 0.952320 cm3/g respectively which further enhance its potential as an excellent adsorbent to improve the filterability of biodiesel compared to beach sand which possessed lowest surface area and lowest pore volume of only 1.2630 m2/g and 0.001751 cm3/g respectively.

Valorization of spent coffee grounds for biodiesel production: blending with higher alcohols, FT-IR, TGA, DSC, and NMR characterizations

Coffee is a global and popular drink with refreshing properties that is consumed in huge amounts daily. During the brewing process, a valuable dark brown organic waste known as spent coffee grounds (SCG) is generated in bulk. SCG has been classified as a promising raw material for the production of various biofuels and added-value products through biorefineries. This paper aims to valorize SCG into biofuel. Firstly, the oil extracted from SCG (SCGO) has been processed into biodiesel fuel. The oil content of SCG has been found to be ~ 12% (by mass). However, SCGO has an extremely high acid value of ~ 24 mg KOH/g oil. Therefore, biodiesel production was conducted through two steps of acid-catalyzed process followed by alkaline-catalyzed transesterification processes along with methanol and heating at 60 °C. It has been found that the properties of spent coffee grounds oil methyl ester (SCGOME) fulfilled ASTM D 6751 biodiesel standards with cetane number of 54.23, kinematic viscosity of 3.73 mm2/s (at 40 °C), flash point of 137.5 °C, density of 891.9 kg/m3 (at 15 °C), oxidation stability of 5.53 h and higher heating value of 39.37 MJ/kg. This is attributed to its excellent degree of unsaturation of 141.54 and long-chain saturated factor of 6.94. Secondly, the qualities of SCGOME and its binary and ternary blends with Euro diesel and three long-chain alcohols of butanol, pentanol, and octanol were considered in this work. This strategy has resulted in a remarkable improvement in both density and cold flow properties and found very close to Euro diesel. Finally, fast, cheap, and reliable characteristics of DSC, FT-IR, TGA, and NMR were examined for the first time in this work to assess the quality of all blends. Such characteristics proved their quality and reliability. In conclusion, this study supports the ongoing research in valorizing SCG to biodiesel through integrated biorefineries towards sustainable circular bioeconomy. It is recommended to conduct detailed engine, emissions, and combustion tests of the blends in the future studies.

Biodiesel production by interesterification of rapeseed oil with methyl formate in presence of potassium alkoxides

An alternative method for the biodiesel or fatty acid alkyl ester (FAAE) synthesis has been proposed—rapeseed oil interesterification with methyl formate. Reaction with methyl formate proceeds at a relatively low temperature (28 °C) instead of 55–65 °C necessary for triglyceride reactions with methanol and other monoesters. Similarly to transesterification with methanol, the product of the reaction with methyl formate consists of two layers. The main product the fatty acid methyl ester (FAME) is located in the top layer, but the process by-product formins forms the bottom layer. In this work, solutions of potassium alkoxides (methoxide, ethoxide, isopropoxide, tert-butoxide) in appropriate alcohols as homogeneous catalysts were used, adhering to the catalyst to oil molar ratio (COMR) 0.1 and methyl formate to oil molar ratio (MFOMR) 18. The FAAE content in the biodiesel layer in presence of all catalysts was 77–81 wt.%, which is lower than the level required by the EN14214 but significantly higher than the FAME content in reactions with methyl acetate under the same conditions. Fuel properties such as flash point, carbon residue, density, viscosity, and cold flow properties were investigated. For samples with MFOMR equal to or higher than 36 FAAE exceed 93% and the main characteristics of samples correspond to the EN14214 limits even without product purification.

Effect of HHO gas enrichment on performance and emissions of a diesel engine fueled by biodiesel blend with kerosene additive

In recent work, biodiesel from cottonseed oil was prepared by transesterification. Then, it was mixed with crude diesel in 20% volumetric percentage producing B20 blend. Moreover, Kerosene was used as an additive to the blend to reduce the cold start problem at low temperature operation in volume percentages of 5% and 10%. HHO gas was developed by water electrolysis with sodium bicarbonate hydroxide catalyst. HHO was developed at a flow rate of 0.3 LPM. The emissions and performance study of diesel engine using cotton ethyl ester blend enriched with HHO gas and kerosene additives was explored in this research. HHO gas with kerosene blends accompanied by ethyl ester cotton oil lessened the brake specific fuel consumption and increased the brake thermal efficiency by 17% and 26.2%, respectively compared to the biodiesel blend B20. The decreases in exhaust gas temperature, CO2, CO and increase in NOx emissions reached to 20.6%, 11.7%, 11% and 14%, respectively by the addition of HHO and 5% kerosene. While, blending 10% of kerosene with HHO gas to the blend resulted in the highest decrease in specific fuel consumption, exhaust gas temperature, CO2 and CO by 17%, 20.7%, 15.45% and 32.65% relative to B20. Biodiesel blend with HHO and 10% kerosene displayed the maximum increases in thermal efficiency and NOx emissions based on B20 by 19% and 11.9%, respectively. HHO enriching is favorable in the combustion characteristics improvement but kerosene enhanced the cold flow properties of biodiesel.

Improving biodiesel made from cottonseed and soyabean oil with partial hydrogenation

Biodiesel limitations such as poor cold-flow properties and oxidation stability limit its usage in diesel engines. Partial hydrogenation is reported to be one of the ways to improve these limitations. Partial hydrogenation of biodiesel made from cottonseed and soyabean oil was studied. Before and after hydrogenation, the fatty acid methyl ester contents of cottonseed and soyabean biodiesel were detected with gas chromatography–mass spectrometry. It was revealed that methyl linolenic and methyl linoleic decreased while methyl stearic and methyl oleic increased after the partial hydrogenation for both soyabean and cottonseed biodiesel. Methyl oleic increased by 127 and 237% for soyabean and cottonseed biodiesel, respectively. A thermogravimetric test was also conducted on the fuel samples to observe the volatilisation of the fuels. There was an increase in fuel properties such as cetane number and kinematic viscosity, while iodine value decreased after partial hydrogenation. In addition, there was no significant change in oxygen content, low-heat value and density for both soyabean and cottonseed biodiesel. In summary, partial hydrogenation is a good method of upgrading biodiesel fuel properties such as cold-flow properties and oxidation stability.

Acetone Prospect as an Additive to Allow the Use of Castor and Sunflower Oils as Drop-In Biofuels in Diesel/Acetone/Vegetable Oil Triple Blends for Application in Diesel Engines.

The present paper investigates the feasibility of using acetone (ACE) in triple blends with fossil diesel (D) and straight vegetable oils (SVOs) as alternative fuel for diesel engines. In this respect, ACE is selected as an oxygenated additivedue to its favorable propertiesto be mixed with vegetable oils and fossil diesel. In fact, the very low kinematic viscosity allows reduces the high viscosity of SVOs. ACE’s oxygen content, low autoignition temperature, and very low cloud point and pour point values highlight its possibilities as an additive in D/ACE/SVO triple blends. Moreover, ACE can be produced through a renewable biotechnological process, an acetone–butanol–ethanol (ABE) fermentation from cellulosic biomass. The SVOs tested were castor oil (CO), which is not suitable for human consumption, and sunflower oil (SO), used as a standard reference for waste cooking oil. The viscosity measurement of the ACE/SVO double blend was considered crucial to choose the optimum proportion, which better fulfilled the specifications established by European standard EN 590. Moreover, some of the most significant physicochemical properties of D/ACE/SVO triple blends, such as kinematic viscosity, cloud point, pour point, and calorific value, were determined to assess their suitability as fuels. The blends were evaluated in a conventional diesel generator through the study of the following parameters: engine power, smoke emissions, and fuel consumption. Despite the low calorific value of ACE limits its ratio in the mixtures due to engine knocking problems, the experimental results reveal an excellent performance for the blends containing up to 16-18% of ACE and 22-24% of SVO. These blends produce similar engine power as to fossil diesel, but with slightly higher fuel consumption. Considerable reductions in emissions of air pollutants, as well as excellent cold flow properties are also obtained with these triple blends. In summary, the use of these biofuels could achieve a substitution of fossil diesel up to 40%, independently on the SVO employed.

CRIAÇÃO DE BANCO DE DADOS PARA SIMULAÇÃO DA PRODUÇÃO DE BIODIESEL. PARTE 1: ESTIMATIVA DE PROPRIEDADES TERMOFÍSICAS DE ÓLEOS VEGETAIS

Pesquisas com foco no desenvolvimento de processos de produção de biocombustíveis têm aumentado significativamente nos últimos anos, principalmente por questões ambientais e econômicas. A busca por matérias-primas de baixo custo, bem como o desenvolvimento de modelos de simulação capazes de prever as condições da produção e as propriedades dos componentes, podem ser o caminho para aumentar o desempenho desses processos. O conhecimento propriedades termofísicas dos componentes da alimentação é crucial para que os resultados sejam similares aos reais. Assim, o objetivo deste trabalho foi avaliar métodos de estimativas de propriedades termofísicas, a fim de desenvolver uma base de dados dos compostos dos óleos vegetais e recomendar os métodos adequados com base na precisão e consistência dos dados obtidos. Ao final deste trabalho recomendou-se o modelo mais viável para cada propriedade avaliada, comparando-se os valores estimados aos dados experimentais disponíveis na literatura.

Addition of diethyl ether on the LHR engine characteristics using biodiesel-eucalyptus blend

ABSTRACT The present experiment deals with the study of addition of diethyl ether on the performance and emission characteristics of LHR engine using papaya methyl ester-eucalyptus oil blends. The test blends are CPME30Eu70 (Carica papaya methyl ester 30% and Eucalyptus oil 70%), CPME30Eu70 + 10% DEE and diesel. The optimum results we get with presence of DEE in CPME30Eu70 in LHR engine. The presence of DEE creates a lean mixture, low viscosity, high cetane number and volatility improves performance for a large degree. The graph depicts that addition of 10% diethyl ether gives the best performance in BSEC, BSFC, BTE and emission wise when coupled with LHR engine. At higher load, BTE for CPME30Eu70 added with 10% in coated engine is 33% and it was 3% higher compared to CPME30Eu70 in uncoated engine. Most notably NOx emission rate is decreased by the presence of the DEE and BSFC is brought under acceptable limit. NOx emission rate while using diethyl ether decreased the emission by 90 ppm when compared to blend without diethyl ether. BSEC decreases in CPME30Eu70 + 10%DEE and betters the performance of diesel in conventional engine. It also said to improve the cold flow properties of the CPME-eucalyptus oil blend.

The Effect of Biodiesel Composition on Characteristics of Blended Summer Diesel Fuel

The blends of varying proportions of biodiesel fuel containing fatty acid methyl esters and triacetin (FAME*), synthesised accordingly to Latvian patent LV 15 373 and summer diesel were prepared, analysed and compared with diesel fuel. The selected fuel properties (viscosity, density, carbon residue and cold flow properties) tested accordingly to standard LVS-EN 14214 have indicated a good potential of FAME*, obtained by synthesis of fatty acid methyl esters (FAME) by simultaneous conversion of glycerol to triacetin as a renewable diesel engine fuel. The results showed that blends containing 5 to 25% of FAME* in summer diesel yielded the properties closely matching that of diesel.Introduction

Production of aviation biofuel from palm kernel oil

In order to partially replace the use of fossil fuels in the aeronautical sector, it is proposed to produce FAME-type biofuels from palm kernel oil. Short chain methyl esters can be used so that the FAME biodiesel have no significant effects on the cold properties of the Jet Fuels when these are mixtures. In this sense, a study of the production of biodiesel FAME from palm kernel by transesterification oil at bench scale was carried out using a batch reactor with the optimal value of the process conditions that were obtained in a previous work but at laboratory level. In that research, the input variables were the methanol-oil ratio, the temperature and the amount of catalyst (% KOH). In this work, the response variable was on the production yield of methyl esters, which were analysed by GC. Physicochemical characterization of the generated biodiesel and an economic analysis of the bank-scale process was carried out to envision a future implementation in the Colombian Air force. Using additives, the improvement of the cold flow properties (such as freezing point and cloud point) of mixtures of FAME of Palm Kernel Oil with Jet Fuel A1 can be contemplated.

Influence of Tetradecyl Methacrylate-N-α-methacrylamide Copolymers as Pour Point Depressants on the Cold Flow Property of Diesel Fuel

High-efficiency pour point depressants (PPDs) for diesel fuel were obtained using a series of tetradecyl methacrylate-N-α-methacrylamide copolymers (C14MC-NMLR) with different molar ratios synthesized through radical polymerization of tetradecyl methacrylate (C14MC) and various forms of N-α-methacrylamide (NMLR, R = -phenyl, -naphthyl, -cyclohexyl, -14a, -16a, -18a). The copolymers were characterized by Fourier transform infrared spectroscopy, 1H nuclear magnetic resonance, and thermogravimetric analysis. Results showed that diesel treated with C14MC-NML-phenyl (9:1) and C14MC-NML-14a (6:1) presented better cold flow properties at 2000 ppm, and the reductions in cold filter-plug point (ΔCFPP) and solid point (ΔSP) were (23 and 10 °C) and (22 and 11 °C) at 2000 ppm, respectively. The depressive effects further improved after compounding. When they were combined at a 1:4 mass ratio, PPDC-6 presented the best depressive effects, and the ΔCFPP and ΔSP reached 25 and 11 °C at 1000 ppm dosage and 28 and 15 °C at 2000 ppm dosage, respectively. Additionally, the crystallization behavior and crystal morphology of each treated diesel were explored.

Production of second-generation biodiesel using low-quality date fruits

This study focused on the valorization of the date syrup obtained from low-quality date fruits to be used as a low-cost alternative medium for producing single cell oil (SCO) by Rhodotorula glutinis PTCC5256, which could further be converted into biodiesel. The higher C/N ratio of date syrup (C/N 70) led to restricting the formation of cell biomass and enhancing the biosynthesis of SCO. The maximal cell biomass and lipid productivities were obtained 72 mg/L/h and 17 mg/L/h by C/N ratios of 20 and 70, respectively. Although the obtained biodiesel met the international standards for cold filter plugging point (4.92 °C), iodine value (87.22 g I2/100 g oil), cetane number (52.26), higher heating value (40.19 MJ/kg), cloud point (6.29 °C), pour point (0.00 °C), density (878 kg/m3), kinematic viscosity (4.30 mm2/s) and oxidation stability (7.87 h), its weak cold-flow properties might limit its application in cold areas in comparison with diesel fuel.

Novel bio-based solid acid catalyst derived from waste yeast residue for biodiesel production

Single cell oils or microbial lipids produced by oleaginous microorganisms are being utilized for various applications such as nutrition, fuels and valuable chemicals. However, after the extraction of value added products from microbial cells, the residue is generally burned or discarded. In the present study, synthesis of a novel bio-based solid acid catalyst from waste yeast residue has been carried out through sulfonation for biodiesel production. The obtained yeast residue based solid acid (YSA) catalyst showed higher fatty acid methyl ester (FAME) yield of 96.2 wt % for waste cooking oil at 60 °C and 94.8 wt % for yeast oil at 70 °C with 4 wt % catalyst concentration and 10:1 methanol to oil molar ratio. The FAME profile indicated the presence of elevated monounsaturated fatty acid content with improved oxidative stability and cold flow properties. The catalyst revealed high catalytic activity, high thermal stability and can be regenerated with its activity maintained up to four cycles. Furthermore, the biodiesel properties were abided with the international fuel standards.

Enhancement of oxidative stability and cold flow properties of coconut oil using natural antioxidant additives for development of bio-lubricant

Coconut oil is less preferred for lubrication purposes, particularly, in high-temperature applications, due to their low thermal stability. Chemical additives for improvements tend to make coconut oil less bio-sustainable and more hazardous. Using natural antioxidants for enhancing oxidative stability has been successfully implemented in food industry. The present study investigates the application of three natural additives – ginger, black pepper and garlic, as possible substitutes for chemical additives in enhancing lubrication properties of coconut oil. In addition to enhancing thermal stability, these natural additives mixed in small proportions could help bring down pour point of coconut oil. Adding traces of food additive, propylene glycol, lubricant samples showed impressive performance in terms of viscosity, friction and wear.

Polyunsaturated fatty acids-enriched lipid from reduced sugar alcohol mannitol by marine yeast Rhodosporidiobolus fluvialis Y2

Brown macroalgae is a promising marine biomass for the production of bioethanol and biodiesel fuels. Here we investigate the biochemical processes used by marine oleaginous yeast for assimilating the major carbohydrate found in brown macroalgae. Briefly, yeast Rhodosporidiobolus fluvialis strain Y2 was isolated from seawater and grown in minimal medium containing reduced sugar alcohol mannitol as the sole carbon source with a salinity comparable to seawater. Conditions limiting nitrogen were used to facilitate lipid synthesis. R. fluvialis Y2 yielded 55.1% (w/w) and 39.1% (w/w) of lipids, per dry cell weight, from mannitol in the absence and presence of salinity, respectively. Furthermore, mannitol, as a sugar source, led to an increase in the composition of polyunsaturated fatty acids, linoleic acid (C18:2) and linolenic acid (C18:3), compared to glucose. This suggests that oxidation of mannitol leads to the activation of NADH-dependent fatty acid desaturases in R. fluvialis Y2. Such fatty acid composition may contribute to the cold-flow properties of biodiesel fuels. Our results identified a salt-tolerant oleaginous yeast species with unique metabolic traits, demonstrating a key role as a decomposer in the global carbon cycle through marine ecosystems. This is the first study on mannitol-induced synthesis of lipids enriched with polyunsaturated fatty acids by marine yeast.

Recycling of kebab restoration grease for bioenergy production through acoustic cavitation

The use of renewable energies to combat climate change is one of the greatest goals for humanity. To achieve this objective, one alternative is to valorize and recycle wastes, i.e. food waste, generated daily due to our way of life. Every day, human beings generate thousands of tons of this organic matter that can be recycled to produce bioenergy. Food waste is a source of carbon that must be included into the carbon dioxide cycle. In this manuscript, we propose to recycle the organic waste produced in a kebab local restaurant through biodiesel production, assisted by clean energy i.e. ultrasound. Biodiesel of both chicken grease and a mixture of beef-lamb were synthesized and optimized by response surface methodology and desirability function. Fatty acid methyl ester yields were higher (97.42% w/w for chicken grease and 96.98 for beef-lamb grease) than the minimum threshold established by European regulation EN 14214 (≥96.5% w/w). Although, cold-filter plugging point and oxidation stability resulted in values far from those established by the EN 14214 standard. To improve them while meeting standard threshold, both antifreeze and antioxidant were added following a design of experiments. The addition of antioxidant t-butyl-hydroxyquinone (TBHQ) at concentrations between 800 and 900 ppm and a commercial antifreeze at concentrations above 0.08% v/v, significantly improved biofuel quality in terms of storage and cold flow properties. We can conclude that animal fat residues from kebab restoration can provide suitable biodiesel if antioxidants and antifreezes are added.