In the present study,an approximation is used to study viscosity as a function of pressure at different temperatures.The correlation so obtained is applied to study the viscosity of biodiesels extracted from soybean,V...In the present study,an approximation is used to study viscosity as a function of pressure at different temperatures.The correlation so obtained is applied to study the viscosity of biodiesels extracted from soybean,Vistive soybean,canola,used canola,coconut and rapeseed.The computed values of viscosity from the proposed model were found to be in good agreement with experimental data throughout the range of pressure and temperature studied.The maximum average absolute relative deviation(AARD%)and mean AARD%are found to be 0.52 and 0.20,respectively,over the entire range of pressure(0.1-140 MPa)and temperature(283.15-373.15 K)for all biodiesels except rapeseed biodiesel,for which the values are 1.1 and 0.62,respectively.Furthermore,this work includes the very first investigation conducted so far on the variation of the pressure-viscosity coefficient(PVC)with pressure at different temperatures for biodiesels.The variation in PVC with the temperature is more sensitive at elevated pressures as compared to atmospheric pressure whereas the variation in PVC with pressure is more sensitive at elevated temperatures as compared to room temperature.展开更多
The incessant pressure of energy requirements by the growing global populace has led to the exploration of unconventional methods to produce renewable and sustainable fuels.Among these,biodiesel is most suited to the ...The incessant pressure of energy requirements by the growing global populace has led to the exploration of unconventional methods to produce renewable and sustainable fuels.Among these,biodiesel is most suited to the present needs of eco-friendly standards to keep the atmosphere free from residual emissions.Various fuel-modification methods were developed over a couple of decades to make biodiesel suitable for diesel engines.In the present research,Jatropha curcas biodiesel and waste-cooking-oil(WCO)biodiesel were used to craft a unique binary blend to obtain desirable fuel properties and operational suitability for the diesel engine.The blend with 80% WCO biodiesel and 20% J.curcas biodiesel,which had the most suitable fuel properties,was tested on a four-stroke single-cylinder vertical diesel engine.The emissions and operational parameters were analysed and compared with diesel.The results of the study indicated that engine emissions for binary blend,carbon monoxide and unburnt hydrocarbon emissions were highly reduced,and carbon dioxide and nitrogen oxide(NO_(x))emissions increased relative to diesel.At full load,NO_(x) emission was found to be 51.32% higher than that from diesel and 3.8% lower than that from WCO biodiesel.Engine performance showed that for the binary blend,at full load,the brake-specific fuel consumption was 396.82 g/kWh,which was 15.26% higher,and the brake thermal efficiency was 22.7%,which was 2.74% lower than regular diesel fuel.The present study suggests that the binary blend of J.curcas biodiesel and WCO biodiesel can be a promising approach towards advancements in the fuel properties of biodiesels.展开更多
The objective of this study was to investigate the possibility of fitting spline regression models for power take-off(PTO)performance characteristics of an agricultural tractor tested with four different fuels,includi...The objective of this study was to investigate the possibility of fitting spline regression models for power take-off(PTO)performance characteristics of an agricultural tractor tested with four different fuels,including diesel fuel(B0)and three biodiesel blends made of canola oil(B10:10%biodiesel+90%petro-diesel blend;B20:20%biodiesel+90%petro-diesel blend;B30:30%biodiesel+90%petro-diesel blend).The performance characteristics evaluated were PTO power,engine torque,engine fuel consumption,and specific fuel consumption.Due to sharp slopes in measured quantities around the nominal engine speed(2200 r/min),compared to the standard regression method,the spline regression models suited well to the experimental data with coefficient of determination R2=0.99 for PTO power and engine torque.R2 varied between 0.97 and 0.99 for fuel consumption and 0.91 and 0.95 for specific fuel consumption.The weaker correlation found for specific fuel consumption could be attributed to profound fluctuations in measured data causing atypical pattern in the corresponding graphs around the nominal engine speed.It was concluded that splines were useful to accurately predict the measured PTO power and engine torque.Neither standard methods nor splines were sufficient to obtain very good regression models for specific fuel consumption.展开更多
Alternative methods for biodiesel purification that focus on ease of operation,cost reduction,and elimination of contaminated residues or that are easier to treat have received more attention.The dry wash route was us...Alternative methods for biodiesel purification that focus on ease of operation,cost reduction,and elimination of contaminated residues or that are easier to treat have received more attention.The dry wash route was used as an alternative to the wet route in biodiesel production.Filter membranes were developed based on cellulose nanofibers as the matrix and sugarcane bagasse fibers or soy hulls,as reinforcement to the matrix,before and after two chemical treatments(carboxymethylation and regeneration with sulfuric acid).The filters were characterized by permeability capacity,morphology,wettability,porosity,SEM and mechanical properties.The filtered biodiesel was also completely characterized.One of the major impacts of dry purification of biodiesel was the glycerin content after filtration.The filters CNFBR 20-28,CNFSR 5-28,CNFSR 5-35,and CNFBC 5-28 produced purified biodiesel with glycerin content below 0.02%(200 mg/L).Another relevant fact is related to the best results for acidity index,combined alkalinity,and glycerin content,obtained by the regenerated filter CNFBR 20-28,which presented a considerable permeate flow rate value above 4145 L h^(-1) m^(-2),which can be related to compacted lamellar layers observed by SEM.The produced filters were applied to biodiesel purification using a low-pressure filtration system and a simple vacuum pump,which resulted in an appreciable reduction in cost.The produced filter with sugarcane bagasse fiber carboxymethylated at 28 mesh of granulometry was efficient for biodiesel purification,including the efficient removal of free glycerin,in agreement with the standards defined by the national controlling agencies.展开更多
Traditional biodiesel production primarily uses methanol as the acyl acceptor,but its toxicity to lipase increases process complexity and operational difficulty elevate manufacturing costs.This study aimed to explore ...Traditional biodiesel production primarily uses methanol as the acyl acceptor,but its toxicity to lipase increases process complexity and operational difficulty elevate manufacturing costs.This study aimed to explore a new method for enzymatic synthesis of biodiesel with methyl methacrylate(MMA)as acyl acceptor.Meanwhile,a 1,3-position specific lipase Lipozyme RM IM was applied as biocatalyst,which enables simultaneous production of biodiesel(FAMEs)and methacrylate fatty acid glycerides(MFAGs)via specific sn-1,3 transesterification of MMA with triglyceride.Under the optimal reaction conditions:temperature of 50℃,molar ratio of 4:1 for MMA to triglyceride,enzyme dosage of 7.5%(mass),and an extra water addition of 0.5%(mass);triglyceride conversion rate of 97%,and FAMEs yield of 65%could be obtained.Simultaneously,the multistage short-path distillation and column chromatographic method were combined used for the separation of the mixed products.Finally,the purity of FAME,MFADG,DMFAG,and MMFAG were 98%,97.8%,95.3%,and 81.78%,respectively.In this new approach,MMA demonstrates lower toxicity to lipases,allowing for straightfo rward addition of all the substrates without complex addition process,and enhancing operational feasibility.Meanwhile,the by-products of MFAGs could be applied as monomers in varnishes and protective coatings,which increased the value of the products.Thus,this investigation providing an alternative way to produce biodiesel,and providing a new pathway for the sustainable development of biodiesel.展开更多
Fuel injection properties,including the injection rate(temporal aspects)and spray behavior(spatial aspects),play a crucial role in the combustion efficiency and emissions of diesel engines.This study investigates the ...Fuel injection properties,including the injection rate(temporal aspects)and spray behavior(spatial aspects),play a crucial role in the combustion efficiency and emissions of diesel engines.This study investigates the effects of different ethanol-biodiesel-diesel(EBD)blends on the injection performance in diesel engines.Experimental tests are conducted to examine key injection parameters,such as spray penetration distance,spray cone angle,and droplet size,alongside an analysis of coupling leakage.The main findings are as follows:(1)The injection behavior of ethanol and diesel differs significantly.The addition of ethanol reduces the density,viscosity,and modulus of elasticity of the fuel mixture.While the injection advance angle,penetration distance,and Sauter mean diameter show minimal changes,the spray cone angle and coupling leakage increase notably.These alterations may disrupt the“fuelair-chamber”matching characteristics of the original engine,potentially affecting performance.(2)In contrast,the injection performance of biodiesel ismore similar to that of diesel.As biodiesel content increases,the density,viscosity,and modulus of elasticity of the blended fuel also grow.Though changes in injection timing,penetration distance,and spray cone angle remain minimal,the Sauter mean diameter experiences a slight increase.The“air-fuel chamber”compatibility of the original engine is largely unaffected,though fuel atomization slightly deteriorates.Blending up to 20%biodiesel and 30%ethanol with diesel effectively compensates for the shortcomings of using single fuels,maintaining favorable injection dynamics while enhancing lubrication and sealing performance of engine components.展开更多
Biodiesel is a clean and renewable energy,and it is an effective measure to optimize engine combustion fueled with biodiesel to meet the increasingly strict toxic and CO_(2) emission regulations of internal combustion...Biodiesel is a clean and renewable energy,and it is an effective measure to optimize engine combustion fueled with biodiesel to meet the increasingly strict toxic and CO_(2) emission regulations of internal combustion engines.A suitable-scale chemical kinetic mechanism is very crucial for the accurate and rapid prediction of engine combustion and emissions.However,most previous researchers developed the mechanism of blend fuels through the separate simplification and merging of the reduced mechanisms of diesel and biodiesel rather than considering their cross-reaction.In this study,a new reduced chemical reaction kinetics mechanism of diesel and biodiesel was constructed through the adoption of directed relationship graph (DRG),directed relationship graph with error propagation,and full-species sensitivity analysis (FSSA).N-heptane and methyl decanoate (MD) were selected as surrogates of traditional diesel and biodiesel,respectively.In this mechanism,the interactions between the intermediate products of both fuels were considered based on the cross-reaction theory.Reaction pathways were revealed,and the key species involved in the oxidation of n-heptane and MD were identified through sensitivity analyses.The reduced mechanism of n-heptane/MD consisting of 288 species and 800 reactions was developed and sufficiently verified by published experimental data.Prediction maps of ignition delay time were established at a wide range of parameter matrices (temperature from 600 to 1 700 K,pressure from 10 bar to 80 bar,equivalence ratio from 0.5 to 1.5) and different substitution ratios to identify the occurrence regions of the crossreaction.Concentration and sensitivity analyses were then conducted to further investigate the effects of cross-reactions.The results indicate temperature as the primary factor causing cross-reactivity.In addition,the reduced mechanism with cross-reactions was more accurate than that without cross-reactions.At 700–1 000 K,the cross-reactions inhibited the consumption of n-heptane/MD,which resulted in a prolonged ignition delay time.At this point,the elementary reaction,NC_(7)H_(16)+OH<=>C_(7)H_(15)-2+H_(2)O,played a dominant role in fuel consumption.Specifically,the contribution of the MD consumption reaction to ignition decreased,and the increased generation time of OH,HO_(2),and H_(2)O_(2) was directly responsible for the increased ignition delay.展开更多
The current work includes a numerical investigation of the effect of biodiesel blends with different aluminum oxide nanoparticle concentrations on the combustion process in the cylinder of a diesel engine.IC Engine Fl...The current work includes a numerical investigation of the effect of biodiesel blends with different aluminum oxide nanoparticle concentrations on the combustion process in the cylinder of a diesel engine.IC Engine Fluent,a specialist computational tool in the ANSYS software,was used to simulate internal combustion engine dynamics and combustion processes.Numerical analysis was carried out using biodiesel blends with three Al_(2)O_(3) nanoparticles in 50,100,and 150 ppm concentrations.The tested samples are called D100,B20,B20A50,B20A100,and B20A150 accordingly.The modeling runs were carried out at various engine loads of 0,100,and 200 Nm at a rated speed of 1800 rpm.The combustion characteristics are improved due to the catalytic effect and higher surface area of nano additives.The results showed the improvements in the combustion process as the result of nanoparticle addition,which led to the higher peak cylinder pressure.The increases in the peak cylinder pressures for B20A50,B20A100,and B20A150 about B20 were 3%,5%,and 8%,respectively,at load 200 Nm.The simulation found that the maximum temperature for biodiesel blends diesel was higher than pure diesel;this was due to higher hydrocarbon values of B20.Also,nano-additives caused a decrease in temperatures in the combustion of biofuels.展开更多
In the quest to develop high-performance lubrication additives,a novel nanocomposite comprising biodiesel soot modified by silver(Ag/BDS)was synthesized.The tribological behavior of Ag/BDS nanocomposite as an additive...In the quest to develop high-performance lubrication additives,a novel nanocomposite comprising biodiesel soot modified by silver(Ag/BDS)was synthesized.The tribological behavior of Ag/BDS nanocomposite as an additive for liquid paraffin(LP)were systematically investigated using response surface methodology.To elucidate the friction and wear mechanisms associated with the Ag/BDS nanocomposite,various analytical techniques were employed,including scanning electron microscopy with energy-dispersive spectroscopy(SEM/EDS),Raman spectroscopy,and molecular dynamics simulations.The results show that the concentration of Ag/BDS has a significant impact on the tribological properties of LP under different applied loads and sliding speeds.Notably,LP containing 0.25%Ag/BDS shows the most favorable tribological performance and in comparison,to pure LP,the average friction coefficient and average wear volume have been reduced by 42.7%and 21.2%,respectively.The mechanisms underlying the reduction in friction and anti-wear mechanism of Ag/BDS have been attributed to the excellent synergies of Ag and BDS.Specifically,the Ag particles facilitate the incorporation of BDS particles in the formation of uniform boundary lubrication films.展开更多
The optimization of reaction processes is crucial for the green, efficient, and sustainable development of the chemical industry. However, how to address the problems posed by multiple variables, nonlinearities, and u...The optimization of reaction processes is crucial for the green, efficient, and sustainable development of the chemical industry. However, how to address the problems posed by multiple variables, nonlinearities, and uncertainties during optimization remains a formidable challenge. In this study, a strategy combining interpretable machine learning with metaheuristic optimization algorithms is employed to optimize the reaction process. First, experimental data from a biodiesel production process are collected to establish a database. These data are then used to construct a predictive model based on artificial neural network (ANN) models. Subsequently, interpretable machine learning techniques are applied for quantitative analysis and verification of the model. Finally, four metaheuristic optimization algorithms are coupled with the ANN model to achieve the desired optimization. The research results show that the methanol: palm fatty acid distillate (PFAD) molar ratio contributes the most to the reaction outcome, accounting for 41%. The ANN-simulated annealing (SA) hybrid method is more suitable for this optimization, and the optimal process parameters are a catalyst concentration of 3.00% (mass), a methanol: PFAD molar ratio of 8.67, and a reaction time of 30 min. This study provides deeper insights into reaction process optimization, which will facilitate future applications in various reaction optimization processes.展开更多
Replacement of volatile organic compounds （VOCs） by greener or more environmentally sustainable solvents is becoming increasingly important due to the increasing health and environmental concerns as well as economic...Replacement of volatile organic compounds （VOCs） by greener or more environmentally sustainable solvents is becoming increasingly important due to the increasing health and environmental concerns as well as economic pressures associated with VOCs. Solvents that are derived from biomass, namely bio-derived solvents, are a type of green solvent that have attracted intensive investigations in recent years because of their advantages over con- ventional VOCs, such as low toxicity, biodegradability and renewability. This review aims to summarize the use of bio-derived solvents in solvent extraction applications, with special emphasis given to utilization of biodiesels and terpenes. Compared with the conventional VOCs, the overall performance of these bio-derived solvents is comparable in terms of extraction yields and selectivity for natural product extraction and no difference was found for metal extraction. To date most researchers have focused on laboratory scale thermodynamics studies. Future work is required to develop and test new bio-derived solvents and understand the kinetic performance as well as solvent extraction nilnt nlant studies.展开更多
Biodiesel, an environmentally friendly biofuel with similar flow and combustion properties as petroleum-based diesel and low emission profile, which is commonly prepared from triglyceride （TG） sources such as vegeta...Biodiesel, an environmentally friendly biofuel with similar flow and combustion properties as petroleum-based diesel and low emission profile, which is commonly prepared from triglyceride （TG） sources such as vegetable oils, animal fats, and waste greases, holds good promises as an alternative to diesel fuel. Alternate fuels for diesel engines have become increasingly important due to diminishing petroleum reserves and awareness of the increased environmental consequences of emissions from petroleum-fuelled engines, as the world is confronted with an energy crisis. Currently, the production of methyl or ethyl esters from edible oils is much more expensive than that of diesel fuels due to the relatively high costs of vegetable oils （about four times the cost of diesel in China）. Methyl esters produced from such oils can be expected to compete economically with diesel fuels, and there is a need to explore low cost alternate feedstocks for the production of biodiesel. Rapeseed is little sensitive to crop input levels, allowing reduction of tillage, irrigation, and weed control. Significant yield increases will be attained using new hybrids and better crop management. Rapeseed cultures in seasonal set-aside lands such as Dongting Lake surroundings can significantly decreases the amount of subsides spent for agricultural overproduction in China, which leads to an increase in farmer incomes as well as the creation of new employment. This significantly lowers production costs, reduces environmental impact, and increases final energy gains. Our rapeseed oil is good source for biodiesel with respect to high oil content and proper fatty acid composition.展开更多
To obtain insight into the catalytic reaction mechanism of biodiesels over ZSM-5 zeolites,the pyrolysis and catalytic pyrolysis of methyl butanoate,a biodiesel surrogate,with H-type ZSM-5(HZSM-5)were performed in a fl...To obtain insight into the catalytic reaction mechanism of biodiesels over ZSM-5 zeolites,the pyrolysis and catalytic pyrolysis of methyl butanoate,a biodiesel surrogate,with H-type ZSM-5(HZSM-5)were performed in a flow rereac tor under atmospheric pressure.The pyrolysis products were identified and quantified using gas chroma to graphy-mass spec trome try(GC-MS).Kine tic modelling and experimental results revealed that H-atom abstraction in the gas phase was the primary pathway for methyl butanoate decomposition during pyrolysis,but dissociating to ketene and methanol over HZSM-5 was the primary pathway for methyl butanoate consumption during catalytic pyrolysis.The initial decomposition temperature of methyl butanoate was reduced by approximately 300 K over HZSM-5 compared to that for the uncatalyzed reaction.In addition,the apparent activation energies of methyl butanoate under catalytic pyrolysis and homogeneous pyrolysis conditions were obtained using the Arrhenius equation.The significantly reduced apparent activation energy confirmed the catalytic performance of HZSM-5 for methyl but anoa te pyrolysis.The act iva tion t empera ture may also affec t some catalytic proper ties of HZSM-5.Overall,this study can be used to guide subsequent catalytic combustion for practical biodiesel fuels.展开更多
Oil content from seed kernels of Xanthoceras sorbifolia from 13 areas in China was analyzed by gas chromatography–mass spectrometry to determine oil characteristics and biodiesel properties. The seeds had a high kern...Oil content from seed kernels of Xanthoceras sorbifolia from 13 areas in China was analyzed by gas chromatography–mass spectrometry to determine oil characteristics and biodiesel properties. The seeds had a high kernel percentage (53.67%± 7.51), oil content (52.21%± 4.01), and biodiesel yield (99.77%± 0.21). Among the fatty acids in the oil were high percentages of linoleic acid (41.66 ± 2.26)% and oleic acid (28.44%± 2.03). Most of the fuel properties complied well with the ASTM D6751-10, EN 14214-08, and GB/T 20828-2014 standards. The 13 sampling areas were grouped into four clusters based on different kernel percentage, oil content, biodiesel yield, and fatty acid composition. The results showed that the quality of kernel oils from seeds from Ar Horqin Banner was the best, although kernel oils from seeds in all 13 areas were suitable for biodiesel production. This study provides a basis for selecting optimal sites to harvest seeds from X. sorbifolia.展开更多
The inexpensive and moisture-stable Lewis-acidic ionic liquids were prepared and applied for transesterification of soybean oil to biodiesel.The influences of molar ratio of methanol to soybean oil,reaction temperatur...The inexpensive and moisture-stable Lewis-acidic ionic liquids were prepared and applied for transesterification of soybean oil to biodiesel.The influences of molar ratio of methanol to soybean oil,reaction temperature and amount of ionic liquids were investigated.The transesterification of soybean oil to biodiesel catalyzed by choline chloride·xZnCl2 ionic liquids showed many advantages such as mild conditions and lower cost.On the other hand,the non-ideal yield and complicated separation between biodiesel and soybean oil were also investigated and analyzed.The improvement on the systems of choline chloride·xZnCl2 was proposed for further investigation.展开更多
The production of biodiesel through a transesterification method produces a large amount of wastewater that contains high levels of chemical oxygen demand （COD） and oil and grease （O＆G）. Currently, flotation is t...The production of biodiesel through a transesterification method produces a large amount of wastewater that contains high levels of chemical oxygen demand （COD） and oil and grease （O＆G）. Currently, flotation is the conventional primary treatment for O＆G removal prior to biological treatments. In this study, electrocoagulation （EC） was adopted to treat the biodiesel wastewater. The effects of initial pH, applied voltage, and reaction time on the EC process for the removal of COD, O＆G, and suspended solids （SS） were investigated using one factor at a time experiment. Furthermore, the Box-Behnken design, an experimental design for response surface methodology （RSM）, was used to create a set of 15 experimental runs needed for optimizing of the operating conditions. Quadratic regression models with estimated coefficients were developed to describe the pollutant removals. The experimental results show that EC could effectively reduce COD, O＆G, and SS by 55.43%, 98.42%, and 96.59%, respectively, at the optimum conditions of pH 6.06, applied voltage 18.2 V, and reaction time 23.5 min. The experimental observations were in reasonable agreement with the modeled values.展开更多
Biodiesel industrial production based on a solid base catalyst in a fixed-bed was simulated. The lab and bench scale experiments were carded out effectively, in which the kinetic model is established and it can descri...Biodiesel industrial production based on a solid base catalyst in a fixed-bed was simulated. The lab and bench scale experiments were carded out effectively, in which the kinetic model is established and it can describe the transesterification reaction well. The Antoine equation of biodiesel is regressed with the vapor-liquid data cited of literature. The non-random two liquid （NRTL） model is applied to describe the system of fatty acid methyl ester （FAME）, methanol and glycerol and parameters are obtained. The Ternary phase map is obtained from Aspen Plus via the liquid-liquid equilibrium （LLE） data. In order to describe the production in a fixed-bed performs in industrial scale after being magnified 1 000 times, the Aspen Plus simulation is employed, where two flowsheets are simulated to predict material and energy consumption. The simulation results prove that at least 350. 42 kW energy consumption can be reduced per hour to produce per ton biodiesel compared with data reported in previous references.展开更多
Since the production cost of biodiesel is now the main hurdle limiting their applicability in some areas, catalytic cracking reactions represent an alternative route to utilization of vegetable oils and animal fats. H...Since the production cost of biodiesel is now the main hurdle limiting their applicability in some areas, catalytic cracking reactions represent an alternative route to utilization of vegetable oils and animal fats. Hence, catalytic transformation of oils and fats was carried out in a laboratory-scale two-stage riser fluid catalytic cracking （TSRFCC） unit in this work. The results show that oils and fats can be used as FCC feed singly or co-feeding with vacuum gas oil （VGO）, which can give high yield （by mass）of liquefied petroleum gas （LPG）, C2-C4 oletms, tor example 45% LPG, 47% C2-C4 olefins, and 77.6% total liquid yield produced with palm oil cracking. Co-feeding with VGO gives a high yield of LPG （39.1%） and propylene （18.1%）. And oxygen element content is very low （about 0.5%） in liquid products, hence, oxygen is removed in the form of H2O, CO and CO2. At the same time, high concentration of aromatics （C7-C9 aromatics predominantly） in the gasoline fraction is obtained after TSRFCC reaction of palm oil, as a result of large amount of hydrogen-transfer, cyclization and aromatization reactions, Additionally, most of properties of produced gasoline and diesel oil fuel meet the requirements of national standards, containing little sulfur. So TSRFCC technology is thought to be an alternative processing technology leading to production of clean fuels and light olefins.展开更多
The catalytic performance of KOH/mordenite has been studied for transesterification of palm oil using a batch reactor and a packed-bed reactor at 60 C and atmospheric pressure.The KOH/mordenite processed transesterifi...The catalytic performance of KOH/mordenite has been studied for transesterification of palm oil using a batch reactor and a packed-bed reactor at 60 C and atmospheric pressure.The KOH/mordenite processed transesterification in the batch reactor gave the highest methyl ester yield of96.7%under optimum conditions,while a methyl ester content over 94.5%was obtained in the packed-bed reactor.This comparison indicates that transesterification in a batch-type reactor gives a higher methyl ester yield than that of a continuous-flow reactor.Dealumination was found in the calcined catalysts and had a significant effect on the physical structure and chemical composition of the catalysts.Leaching of the potassium species was negligible,whereas depositing and washing of the reacted mixture with acetone on the catalyst surface were observed by FTIR.展开更多
文摘In the present study,an approximation is used to study viscosity as a function of pressure at different temperatures.The correlation so obtained is applied to study the viscosity of biodiesels extracted from soybean,Vistive soybean,canola,used canola,coconut and rapeseed.The computed values of viscosity from the proposed model were found to be in good agreement with experimental data throughout the range of pressure and temperature studied.The maximum average absolute relative deviation(AARD%)and mean AARD%are found to be 0.52 and 0.20,respectively,over the entire range of pressure(0.1-140 MPa)and temperature(283.15-373.15 K)for all biodiesels except rapeseed biodiesel,for which the values are 1.1 and 0.62,respectively.Furthermore,this work includes the very first investigation conducted so far on the variation of the pressure-viscosity coefficient(PVC)with pressure at different temperatures for biodiesels.The variation in PVC with the temperature is more sensitive at elevated pressures as compared to atmospheric pressure whereas the variation in PVC with pressure is more sensitive at elevated temperatures as compared to room temperature.
文摘The incessant pressure of energy requirements by the growing global populace has led to the exploration of unconventional methods to produce renewable and sustainable fuels.Among these,biodiesel is most suited to the present needs of eco-friendly standards to keep the atmosphere free from residual emissions.Various fuel-modification methods were developed over a couple of decades to make biodiesel suitable for diesel engines.In the present research,Jatropha curcas biodiesel and waste-cooking-oil(WCO)biodiesel were used to craft a unique binary blend to obtain desirable fuel properties and operational suitability for the diesel engine.The blend with 80% WCO biodiesel and 20% J.curcas biodiesel,which had the most suitable fuel properties,was tested on a four-stroke single-cylinder vertical diesel engine.The emissions and operational parameters were analysed and compared with diesel.The results of the study indicated that engine emissions for binary blend,carbon monoxide and unburnt hydrocarbon emissions were highly reduced,and carbon dioxide and nitrogen oxide(NO_(x))emissions increased relative to diesel.At full load,NO_(x) emission was found to be 51.32% higher than that from diesel and 3.8% lower than that from WCO biodiesel.Engine performance showed that for the binary blend,at full load,the brake-specific fuel consumption was 396.82 g/kWh,which was 15.26% higher,and the brake thermal efficiency was 22.7%,which was 2.74% lower than regular diesel fuel.The present study suggests that the binary blend of J.curcas biodiesel and WCO biodiesel can be a promising approach towards advancements in the fuel properties of biodiesels.
文摘The objective of this study was to investigate the possibility of fitting spline regression models for power take-off(PTO)performance characteristics of an agricultural tractor tested with four different fuels,including diesel fuel(B0)and three biodiesel blends made of canola oil(B10:10%biodiesel+90%petro-diesel blend;B20:20%biodiesel+90%petro-diesel blend;B30:30%biodiesel+90%petro-diesel blend).The performance characteristics evaluated were PTO power,engine torque,engine fuel consumption,and specific fuel consumption.Due to sharp slopes in measured quantities around the nominal engine speed(2200 r/min),compared to the standard regression method,the spline regression models suited well to the experimental data with coefficient of determination R2=0.99 for PTO power and engine torque.R2 varied between 0.97 and 0.99 for fuel consumption and 0.91 and 0.95 for specific fuel consumption.The weaker correlation found for specific fuel consumption could be attributed to profound fluctuations in measured data causing atypical pattern in the corresponding graphs around the nominal engine speed.It was concluded that splines were useful to accurately predict the measured PTO power and engine torque.Neither standard methods nor splines were sufficient to obtain very good regression models for specific fuel consumption.
基金supported by the Minas Gerais State’s Foundation for Research Support(FAPEMIG,Brazil,Process CEX-APQ-01651-17,RED-00224-23,and PPM-00645-17).
文摘Alternative methods for biodiesel purification that focus on ease of operation,cost reduction,and elimination of contaminated residues or that are easier to treat have received more attention.The dry wash route was used as an alternative to the wet route in biodiesel production.Filter membranes were developed based on cellulose nanofibers as the matrix and sugarcane bagasse fibers or soy hulls,as reinforcement to the matrix,before and after two chemical treatments(carboxymethylation and regeneration with sulfuric acid).The filters were characterized by permeability capacity,morphology,wettability,porosity,SEM and mechanical properties.The filtered biodiesel was also completely characterized.One of the major impacts of dry purification of biodiesel was the glycerin content after filtration.The filters CNFBR 20-28,CNFSR 5-28,CNFSR 5-35,and CNFBC 5-28 produced purified biodiesel with glycerin content below 0.02%(200 mg/L).Another relevant fact is related to the best results for acidity index,combined alkalinity,and glycerin content,obtained by the regenerated filter CNFBR 20-28,which presented a considerable permeate flow rate value above 4145 L h^(-1) m^(-2),which can be related to compacted lamellar layers observed by SEM.The produced filters were applied to biodiesel purification using a low-pressure filtration system and a simple vacuum pump,which resulted in an appreciable reduction in cost.The produced filter with sugarcane bagasse fiber carboxymethylated at 28 mesh of granulometry was efficient for biodiesel purification,including the efficient removal of free glycerin,in agreement with the standards defined by the national controlling agencies.
文摘Traditional biodiesel production primarily uses methanol as the acyl acceptor,but its toxicity to lipase increases process complexity and operational difficulty elevate manufacturing costs.This study aimed to explore a new method for enzymatic synthesis of biodiesel with methyl methacrylate(MMA)as acyl acceptor.Meanwhile,a 1,3-position specific lipase Lipozyme RM IM was applied as biocatalyst,which enables simultaneous production of biodiesel(FAMEs)and methacrylate fatty acid glycerides(MFAGs)via specific sn-1,3 transesterification of MMA with triglyceride.Under the optimal reaction conditions:temperature of 50℃,molar ratio of 4:1 for MMA to triglyceride,enzyme dosage of 7.5%(mass),and an extra water addition of 0.5%(mass);triglyceride conversion rate of 97%,and FAMEs yield of 65%could be obtained.Simultaneously,the multistage short-path distillation and column chromatographic method were combined used for the separation of the mixed products.Finally,the purity of FAME,MFADG,DMFAG,and MMFAG were 98%,97.8%,95.3%,and 81.78%,respectively.In this new approach,MMA demonstrates lower toxicity to lipases,allowing for straightfo rward addition of all the substrates without complex addition process,and enhancing operational feasibility.Meanwhile,the by-products of MFAGs could be applied as monomers in varnishes and protective coatings,which increased the value of the products.Thus,this investigation providing an alternative way to produce biodiesel,and providing a new pathway for the sustainable development of biodiesel.
基金supported by Innovation Research Project for the training of high-level scientific and technological talents(Technical expert talents)of the Armed Police Force ZZKY20222415“13th Five-Year Plan”military key colleges and key disciplines-Equipment Engineering(Power)-17.
文摘Fuel injection properties,including the injection rate(temporal aspects)and spray behavior(spatial aspects),play a crucial role in the combustion efficiency and emissions of diesel engines.This study investigates the effects of different ethanol-biodiesel-diesel(EBD)blends on the injection performance in diesel engines.Experimental tests are conducted to examine key injection parameters,such as spray penetration distance,spray cone angle,and droplet size,alongside an analysis of coupling leakage.The main findings are as follows:(1)The injection behavior of ethanol and diesel differs significantly.The addition of ethanol reduces the density,viscosity,and modulus of elasticity of the fuel mixture.While the injection advance angle,penetration distance,and Sauter mean diameter show minimal changes,the spray cone angle and coupling leakage increase notably.These alterations may disrupt the“fuelair-chamber”matching characteristics of the original engine,potentially affecting performance.(2)In contrast,the injection performance of biodiesel ismore similar to that of diesel.As biodiesel content increases,the density,viscosity,and modulus of elasticity of the blended fuel also grow.Though changes in injection timing,penetration distance,and spray cone angle remain minimal,the Sauter mean diameter experiences a slight increase.The“air-fuel chamber”compatibility of the original engine is largely unaffected,though fuel atomization slightly deteriorates.Blending up to 20%biodiesel and 30%ethanol with diesel effectively compensates for the shortcomings of using single fuels,maintaining favorable injection dynamics while enhancing lubrication and sealing performance of engine components.
基金Supported by the National Natural Science Foundation of China (Grant No. 52171298)the National Foreign Experts Program (G2023180006L)+1 种基金the Natural Science Foundation of Heilongjiang Province of China (Grant No. ZD2019E003)the Fundamental Research Funds for the Central Universities (Grant No. 3072022TS0303)。
文摘Biodiesel is a clean and renewable energy,and it is an effective measure to optimize engine combustion fueled with biodiesel to meet the increasingly strict toxic and CO_(2) emission regulations of internal combustion engines.A suitable-scale chemical kinetic mechanism is very crucial for the accurate and rapid prediction of engine combustion and emissions.However,most previous researchers developed the mechanism of blend fuels through the separate simplification and merging of the reduced mechanisms of diesel and biodiesel rather than considering their cross-reaction.In this study,a new reduced chemical reaction kinetics mechanism of diesel and biodiesel was constructed through the adoption of directed relationship graph (DRG),directed relationship graph with error propagation,and full-species sensitivity analysis (FSSA).N-heptane and methyl decanoate (MD) were selected as surrogates of traditional diesel and biodiesel,respectively.In this mechanism,the interactions between the intermediate products of both fuels were considered based on the cross-reaction theory.Reaction pathways were revealed,and the key species involved in the oxidation of n-heptane and MD were identified through sensitivity analyses.The reduced mechanism of n-heptane/MD consisting of 288 species and 800 reactions was developed and sufficiently verified by published experimental data.Prediction maps of ignition delay time were established at a wide range of parameter matrices (temperature from 600 to 1 700 K,pressure from 10 bar to 80 bar,equivalence ratio from 0.5 to 1.5) and different substitution ratios to identify the occurrence regions of the crossreaction.Concentration and sensitivity analyses were then conducted to further investigate the effects of cross-reactions.The results indicate temperature as the primary factor causing cross-reactivity.In addition,the reduced mechanism with cross-reactions was more accurate than that without cross-reactions.At 700–1 000 K,the cross-reactions inhibited the consumption of n-heptane/MD,which resulted in a prolonged ignition delay time.At this point,the elementary reaction,NC_(7)H_(16)+OH<=>C_(7)H_(15)-2+H_(2)O,played a dominant role in fuel consumption.Specifically,the contribution of the MD consumption reaction to ignition decreased,and the increased generation time of OH,HO_(2),and H_(2)O_(2) was directly responsible for the increased ignition delay.
文摘The current work includes a numerical investigation of the effect of biodiesel blends with different aluminum oxide nanoparticle concentrations on the combustion process in the cylinder of a diesel engine.IC Engine Fluent,a specialist computational tool in the ANSYS software,was used to simulate internal combustion engine dynamics and combustion processes.Numerical analysis was carried out using biodiesel blends with three Al_(2)O_(3) nanoparticles in 50,100,and 150 ppm concentrations.The tested samples are called D100,B20,B20A50,B20A100,and B20A150 accordingly.The modeling runs were carried out at various engine loads of 0,100,and 200 Nm at a rated speed of 1800 rpm.The combustion characteristics are improved due to the catalytic effect and higher surface area of nano additives.The results showed the improvements in the combustion process as the result of nanoparticle addition,which led to the higher peak cylinder pressure.The increases in the peak cylinder pressures for B20A50,B20A100,and B20A150 about B20 were 3%,5%,and 8%,respectively,at load 200 Nm.The simulation found that the maximum temperature for biodiesel blends diesel was higher than pure diesel;this was due to higher hydrocarbon values of B20.Also,nano-additives caused a decrease in temperatures in the combustion of biofuels.
基金funded by the National Natural Science Foundation of China(52075141)the Open Project of Anhui Province Key Laboratory of Critical Friction Pair for Advanced Equipment(LCFP-2408)+9 种基金Key Research&Development(R&D)Plan of Anhui Province under Grant(2022a05020019)Support Program for Outstanding Young Talents in Anhui Province Colleges and Universities(gxyq2022079)Excellent Research and Innovation Teams Project of Anhui Province's Universities(2022AH010092)Discipline Construction Quality Improvement Project of Chaohu University(kj22fdzy03,XLZ202307,XLZ202301)School-level Scientific Research Project of Chaohu University(XLY-202112)Scientific Research Planning Project of Anhui Provincial(2022AH051726)Anhui Province University Science and Engineering Teachers'Internship Program in Enterprises(2024jsqygz89)Anhui Province College Students'Innovation and Entrepreneurship Training Program(S202410380020)Anhui Province Postdoctoral Research Project(2024A773)Horizontal Research Project of Chaohu University(hxkt20230006).
文摘In the quest to develop high-performance lubrication additives,a novel nanocomposite comprising biodiesel soot modified by silver(Ag/BDS)was synthesized.The tribological behavior of Ag/BDS nanocomposite as an additive for liquid paraffin(LP)were systematically investigated using response surface methodology.To elucidate the friction and wear mechanisms associated with the Ag/BDS nanocomposite,various analytical techniques were employed,including scanning electron microscopy with energy-dispersive spectroscopy(SEM/EDS),Raman spectroscopy,and molecular dynamics simulations.The results show that the concentration of Ag/BDS has a significant impact on the tribological properties of LP under different applied loads and sliding speeds.Notably,LP containing 0.25%Ag/BDS shows the most favorable tribological performance and in comparison,to pure LP,the average friction coefficient and average wear volume have been reduced by 42.7%and 21.2%,respectively.The mechanisms underlying the reduction in friction and anti-wear mechanism of Ag/BDS have been attributed to the excellent synergies of Ag and BDS.Specifically,the Ag particles facilitate the incorporation of BDS particles in the formation of uniform boundary lubrication films.
基金supported by the National Natural Science Foundation of China(22408227,22238005)the Postdoctoral Research Foundation of China(GZC20231576).
文摘The optimization of reaction processes is crucial for the green, efficient, and sustainable development of the chemical industry. However, how to address the problems posed by multiple variables, nonlinearities, and uncertainties during optimization remains a formidable challenge. In this study, a strategy combining interpretable machine learning with metaheuristic optimization algorithms is employed to optimize the reaction process. First, experimental data from a biodiesel production process are collected to establish a database. These data are then used to construct a predictive model based on artificial neural network (ANN) models. Subsequently, interpretable machine learning techniques are applied for quantitative analysis and verification of the model. Finally, four metaheuristic optimization algorithms are coupled with the ANN model to achieve the desired optimization. The research results show that the methanol: palm fatty acid distillate (PFAD) molar ratio contributes the most to the reaction outcome, accounting for 41%. The ANN-simulated annealing (SA) hybrid method is more suitable for this optimization, and the optimal process parameters are a catalyst concentration of 3.00% (mass), a methanol: PFAD molar ratio of 8.67, and a reaction time of 30 min. This study provides deeper insights into reaction process optimization, which will facilitate future applications in various reaction optimization processes.
基金Support from the Australian Research Council (project ID:LP140100650)
文摘Replacement of volatile organic compounds （VOCs） by greener or more environmentally sustainable solvents is becoming increasingly important due to the increasing health and environmental concerns as well as economic pressures associated with VOCs. Solvents that are derived from biomass, namely bio-derived solvents, are a type of green solvent that have attracted intensive investigations in recent years because of their advantages over con- ventional VOCs, such as low toxicity, biodegradability and renewability. This review aims to summarize the use of bio-derived solvents in solvent extraction applications, with special emphasis given to utilization of biodiesels and terpenes. Compared with the conventional VOCs, the overall performance of these bio-derived solvents is comparable in terms of extraction yields and selectivity for natural product extraction and no difference was found for metal extraction. To date most researchers have focused on laboratory scale thermodynamics studies. Future work is required to develop and test new bio-derived solvents and understand the kinetic performance as well as solvent extraction nilnt nlant studies.
文摘Biodiesel, an environmentally friendly biofuel with similar flow and combustion properties as petroleum-based diesel and low emission profile, which is commonly prepared from triglyceride （TG） sources such as vegetable oils, animal fats, and waste greases, holds good promises as an alternative to diesel fuel. Alternate fuels for diesel engines have become increasingly important due to diminishing petroleum reserves and awareness of the increased environmental consequences of emissions from petroleum-fuelled engines, as the world is confronted with an energy crisis. Currently, the production of methyl or ethyl esters from edible oils is much more expensive than that of diesel fuels due to the relatively high costs of vegetable oils （about four times the cost of diesel in China）. Methyl esters produced from such oils can be expected to compete economically with diesel fuels, and there is a need to explore low cost alternate feedstocks for the production of biodiesel. Rapeseed is little sensitive to crop input levels, allowing reduction of tillage, irrigation, and weed control. Significant yield increases will be attained using new hybrids and better crop management. Rapeseed cultures in seasonal set-aside lands such as Dongting Lake surroundings can significantly decreases the amount of subsides spent for agricultural overproduction in China, which leads to an increase in farmer incomes as well as the creation of new employment. This significantly lowers production costs, reduces environmental impact, and increases final energy gains. Our rapeseed oil is good source for biodiesel with respect to high oil content and proper fatty acid composition.
基金This work was supported by the National Natural Science Foundation of China(No.51676176 and No.51976207)the Fundamental Research Funds for the Central Universities(No.WK2320000038)the Foundation of State Key Laboratory of Coal Combustion(No.FSKLCCA1909).
文摘To obtain insight into the catalytic reaction mechanism of biodiesels over ZSM-5 zeolites,the pyrolysis and catalytic pyrolysis of methyl butanoate,a biodiesel surrogate,with H-type ZSM-5(HZSM-5)were performed in a flow rereac tor under atmospheric pressure.The pyrolysis products were identified and quantified using gas chroma to graphy-mass spec trome try(GC-MS).Kine tic modelling and experimental results revealed that H-atom abstraction in the gas phase was the primary pathway for methyl butanoate decomposition during pyrolysis,but dissociating to ketene and methanol over HZSM-5 was the primary pathway for methyl butanoate consumption during catalytic pyrolysis.The initial decomposition temperature of methyl butanoate was reduced by approximately 300 K over HZSM-5 compared to that for the uncatalyzed reaction.In addition,the apparent activation energies of methyl butanoate under catalytic pyrolysis and homogeneous pyrolysis conditions were obtained using the Arrhenius equation.The significantly reduced apparent activation energy confirmed the catalytic performance of HZSM-5 for methyl but anoa te pyrolysis.The act iva tion t empera ture may also affec t some catalytic proper ties of HZSM-5.Overall,this study can be used to guide subsequent catalytic combustion for practical biodiesel fuels.
基金financially supported by the International S&T Cooperation Program of China(2014DFA31140)
文摘Oil content from seed kernels of Xanthoceras sorbifolia from 13 areas in China was analyzed by gas chromatography–mass spectrometry to determine oil characteristics and biodiesel properties. The seeds had a high kernel percentage (53.67%± 7.51), oil content (52.21%± 4.01), and biodiesel yield (99.77%± 0.21). Among the fatty acids in the oil were high percentages of linoleic acid (41.66 ± 2.26)% and oleic acid (28.44%± 2.03). Most of the fuel properties complied well with the ASTM D6751-10, EN 14214-08, and GB/T 20828-2014 standards. The 13 sampling areas were grouped into four clusters based on different kernel percentage, oil content, biodiesel yield, and fatty acid composition. The results showed that the quality of kernel oils from seeds from Ar Horqin Banner was the best, although kernel oils from seeds in all 13 areas were suitable for biodiesel production. This study provides a basis for selecting optimal sites to harvest seeds from X. sorbifolia.
基金Supported by the National High Technology Research and Development Program of China(2007AA06Z202)the National Key Technology Research and Development Program of China(2006BAC02A10)the Distinguished Young Scholars Foundation of Jilin Province(20060114)
文摘The inexpensive and moisture-stable Lewis-acidic ionic liquids were prepared and applied for transesterification of soybean oil to biodiesel.The influences of molar ratio of methanol to soybean oil,reaction temperature and amount of ionic liquids were investigated.The transesterification of soybean oil to biodiesel catalyzed by choline chloride·xZnCl2 ionic liquids showed many advantages such as mild conditions and lower cost.On the other hand,the non-ideal yield and complicated separation between biodiesel and soybean oil were also investigated and analyzed.The improvement on the systems of choline chloride·xZnCl2 was proposed for further investigation.
基金supported by the Energy Policy and Planning Office, Ministry of Energy Royal Thai Government under the grant for supporting conservation of energy
文摘The production of biodiesel through a transesterification method produces a large amount of wastewater that contains high levels of chemical oxygen demand （COD） and oil and grease （O＆G）. Currently, flotation is the conventional primary treatment for O＆G removal prior to biological treatments. In this study, electrocoagulation （EC） was adopted to treat the biodiesel wastewater. The effects of initial pH, applied voltage, and reaction time on the EC process for the removal of COD, O＆G, and suspended solids （SS） were investigated using one factor at a time experiment. Furthermore, the Box-Behnken design, an experimental design for response surface methodology （RSM）, was used to create a set of 15 experimental runs needed for optimizing of the operating conditions. Quadratic regression models with estimated coefficients were developed to describe the pollutant removals. The experimental results show that EC could effectively reduce COD, O＆G, and SS by 55.43%, 98.42%, and 96.59%, respectively, at the optimum conditions of pH 6.06, applied voltage 18.2 V, and reaction time 23.5 min. The experimental observations were in reasonable agreement with the modeled values.
基金The National Basic Research Program of China(973Program)(No.2010CB732206)the National Natural Science Foundation of China(No.21076044,21276050)
文摘Biodiesel industrial production based on a solid base catalyst in a fixed-bed was simulated. The lab and bench scale experiments were carded out effectively, in which the kinetic model is established and it can describe the transesterification reaction well. The Antoine equation of biodiesel is regressed with the vapor-liquid data cited of literature. The non-random two liquid （NRTL） model is applied to describe the system of fatty acid methyl ester （FAME）, methanol and glycerol and parameters are obtained. The Ternary phase map is obtained from Aspen Plus via the liquid-liquid equilibrium （LLE） data. In order to describe the production in a fixed-bed performs in industrial scale after being magnified 1 000 times, the Aspen Plus simulation is employed, where two flowsheets are simulated to predict material and energy consumption. The simulation results prove that at least 350. 42 kW energy consumption can be reduced per hour to produce per ton biodiesel compared with data reported in previous references.
基金the Major Research Plan of PetroChina Company Limited (07-03D-01-01-02-02)
文摘Since the production cost of biodiesel is now the main hurdle limiting their applicability in some areas, catalytic cracking reactions represent an alternative route to utilization of vegetable oils and animal fats. Hence, catalytic transformation of oils and fats was carried out in a laboratory-scale two-stage riser fluid catalytic cracking （TSRFCC） unit in this work. The results show that oils and fats can be used as FCC feed singly or co-feeding with vacuum gas oil （VGO）, which can give high yield （by mass）of liquefied petroleum gas （LPG）, C2-C4 oletms, tor example 45% LPG, 47% C2-C4 olefins, and 77.6% total liquid yield produced with palm oil cracking. Co-feeding with VGO gives a high yield of LPG （39.1%） and propylene （18.1%）. And oxygen element content is very low （about 0.5%） in liquid products, hence, oxygen is removed in the form of H2O, CO and CO2. At the same time, high concentration of aromatics （C7-C9 aromatics predominantly） in the gasoline fraction is obtained after TSRFCC reaction of palm oil, as a result of large amount of hydrogen-transfer, cyclization and aromatization reactions, Additionally, most of properties of produced gasoline and diesel oil fuel meet the requirements of national standards, containing little sulfur. So TSRFCC technology is thought to be an alternative processing technology leading to production of clean fuels and light olefins.
基金supported financially by the National Metal and Materials Technology Center,Thailandthe Center of Excellence on Petrochemical and Materials Technology,Thailand
文摘The catalytic performance of KOH/mordenite has been studied for transesterification of palm oil using a batch reactor and a packed-bed reactor at 60 C and atmospheric pressure.The KOH/mordenite processed transesterification in the batch reactor gave the highest methyl ester yield of96.7%under optimum conditions,while a methyl ester content over 94.5%was obtained in the packed-bed reactor.This comparison indicates that transesterification in a batch-type reactor gives a higher methyl ester yield than that of a continuous-flow reactor.Dealumination was found in the calcined catalysts and had a significant effect on the physical structure and chemical composition of the catalysts.Leaching of the potassium species was negligible,whereas depositing and washing of the reacted mixture with acetone on the catalyst surface were observed by FTIR.
