Rapeseed Oil Methyl Ester Research Articles

Numerical investigation of combustion characteristics of extended coherent flame model 3 zones (ECFM‐3Z) in diesel engines running with biodiesel

AbstractThis research investigates the application of Extended Coherent Flame Model‐3 Zones (ECFM‐3Z) to assess the performance and emissions of rapeseed oil methyl ester (ROME). Experimental tests were carried out using a Lombardini 3 LD 350 model single‐cylinder diesel engine, at 1600–3000 rpm with 200 rpm speed increments, under full load conditions. For numerical analysis, STAR‐CD/ESICE software was employed. Methyl Oleate (C19H36O2) was predicted as the surrogate biodiesel based on Gas Chromatography (GC) analysis and average mass calculation. Notably, the numerical analysis revealed a remarkable similarity in brake power between the experimental and computational investigations. In the range of 2400–3000 rpm, the biodiesel's performance exhibited a maximum deviation of 5%, primarily attributed to pumping, thermal, and friction losses. In terms of emissions, carbon dioxide (CO2) emissions were consistent with the findings of the experimental study, with a maximum disparity of 10%. However, carbon monoxide (CO) emissions ranged from 57% to 65% lower than those observed in the experimental study, while nitrogen oxide (NOx) emissions exhibited a reduction of 63% to 84%. In contrast, oxygen (O2) emissions were notably higher, ranging from 93% to 117% compared to the experimental study, and exhaust temperatures were elevated by 33% to 49% in comparison to the experimental results.

Enzymatic In Situ Interesterification of Rapeseed Oil with Methyl Formate in Diesel Fuel Medium

The purpose of this research was to evaluate the process of enzymatic biodiesel synthesis by directly using rapeseed as a raw material, extracting the oil contained within and interesterifying with a mixture of methyl formate and mineral diesel, choosing the amount of mineral diesel so that the ratio between it and the rapeseed oil in the seeds was 9:1. As the final product of the interesterification process, a mixture of mineral diesel and biodiesel was obtained directly, which is conventionally produced by mixing the mineral diesel and biodiesel. The tests were performed using enzymatic catalysis using the lipase Lipozyme TL TIM. Process optimization was performed using the response surface methodology. A model describing the interaction of three independent variables and their influence on the yield of rapeseed oil methyl esters was developed. The physical and chemical indicators of the product obtained under optimal interesterification conditions were evaluated.

ADVANCEMENTS IN CIVIL EXPLOSIVES: NOVEL FORMULATIONS AND SUSTAINABLE FUEL SOLUTIONS

ABSTRACT. The article presents the development of a new explosive mixture based on agricultural ammonium nitrate, possessing high detonation capability, increased water resistance, and physical stability. The concept for its creation is based on obtaining an oil-in-water (O/W) type microemulsion, produced using vegetable oil. Calculations conducted showed that the use of 100 % rapeseed oil methyl esters compared to diesel fuel improves emulsification by 14 %, reducing emulsification time by 15 %. Due to the structure of the microemulsion, ordinary agricultural ammonium nitrate can successfully retain around 7.5 % of the microemulsion. This amount of fuel phase is sufficient for obtaining an explosive composition with an appropriate oxygen balance. Substituting the porous ammonium nitrate (PAN) with agricultural ammonium nitrate - the cheapest oxidizer for the production of the newly developed explosive mixture, reduces its production cost and significantly increases the competitiveness of the product.

The Effect of Nanoparticle Additives on the Lubricity of Diesel and Biodiesel Fuels

Fuel lubricity is an essential property that ensures the longevity end efficiency of diesel CI engines. Nanomaterials have been shown to have the potential to improve lubricity in many different lubricating substances, including fuels. Moreover, the combustion process has also been shown to improve with the introduction of nanomaterials. This study investigated a series of nanoparticles, including carbon nanoplates, carbon nanotubes, aluminum oxide, zinc oxide, and cerium oxide, as lubricity-enhancing additives for selected fuels. Conventional diesel fuel and rapeseed oil methyl ester, referred to as biodiesel, were chosen as base fuels for modification. The lubricity was evaluated according to the standard test method ASTM 6079 using the HFRR tribometer. The leading lubricity indicators were the wear scar diameter, wear volume, and coefficient of friction. In addition, the worn surface analysis was performed to elucidate the lubrication mechanism. The results show that the addition of nanoparticles can improve the lubricity of both investigated fuels. However, the effect differed among nanoparticles and fuels. In summary, carbon nanotubes could be a rational choice for both fuels. In addition, zinc oxide improved the lubricity of diesel fuel, while carbon nanoplatelets and aluminum oxide nanoparticles showed improvements in the lubricity of biodiesel.

Evaluation of Combustion Stability and Exhaust Emissions of a Stationary Compression Ignition Engine Powered by Diesel/n-Butanol and RME Biodiesel/n-Butanol Blends

In recent years, the interest in renewable fuels has increased mainly due to regulations regulating the permissible limits of toxic components of exhaust gases emitted by reciprocating engines. This paper presents the results of a comparison of the effects of fueling a compression-ignition piston engine with a mixture of diesel fuel and n-butanol, as well as RME (Rapeseed Oil Methyl Esters) biodiesel and n-butanol. The tests were carried out for a constant load and a wide energetic share of fuels in the mixture. The main focus was on the assessment of combustion stability, the uniqueness of the combustion stages, and the assessment of the fuel type influence on the CA50 angle. The tests show that RME offers the possibility of efficient combustion with n-butanol with up to 80% energy share. The share of n-butanol has a positive effect on the engine’s efficiency and very effectively reduces soot emissions. Without the influence on COVIMEP, the share of n-butanol up to 40% in the mixture with diesel fuel and up to 80% in the mixture with RME was recorded. Combustion of RME with n-butanol was more stable. The share of n-butanol in the mixture with diesel fuel caused an increase in NOx emissions, and co-combustion with RME caused a decrease in emissions.

Experimental investigation on the impact of NOx emission in CI engine fueled with rapeseed biodiesel with antioxidant additives

The proposed research aims to investigate the impact of an oxidant, l-ascorbic acid, on the performance and exhaust of a diesel engine that drives on neat rapeseed methyl ester-based oil (RSOME). The antioxidant is supplemented with rapeseed oil methyl ester in a range of amounts (100–400 mg). This research revealed that, without altering the engine, the reactive additives mixture (MERSO + LA300) substantially lowered the NOX and HC emissions of methyl ester in rapeseed oil-fueled engines.

Double‐Bond Isomerization of Rapeseed Oil Methyl Esters in a Continuous Flow Reactor Efficiently Catalyzed by H‐Mordenite

AbstractUnsaturated fatty acids are attractive alternatives to fossil‐based materials as a source of hydrocarbons, but potential applications are limited by the preset chain length of 16–20 carbon atoms. However, if the double bond can be randomly moved along the chain, subsequent bond‐breaking operations such as ethenolysis or oxidative cleavage will give rise to products with chain lengths ranging from 2 to 18 carbon atoms. A process for the double bond isomerization of rapeseed oil methyl esters in a flow‐through reactor using zeolites as the catalyst is herein disclosed. Using H‐mordenite as the catalyst at a flow of 0.125 mL min−1 at 290 °C, near equilibrium isomerization is reached with up to 49% recovery of linear monomeric products after 5 h and up to 44% after 48 h. The main side products are oligomers (3%–15%) and skeletal isomerization products (10%–23%).Practical applications: With a suitable follow‐up modification addressing the double bond (metathesis, ozonolysis, oxidative cleavage), the product mixtures of double‐bond positional isomers can be used in the production of short‐chain base chemicals. In repetitive combination with metathesis catalysis, biofuels with customized chain length distributions can be generated.

Glycerol free biodiesel synthesis by application of methyl formate in enzymatic interesterification of rapeseed oil

ABSTRACT The aim of studies was to investigate the process of enzymatic interesterification of rapeseed oil with methyl formate and to determine the influence of three independent variables on the product yield. After evaluating the effectiveness of three enzymatic preparations, the industrial preparation Lipozyme TL IM was selected for the research. Using the surface response methodology, a model describing the dependence of the yield of rapeseed methyl esters on the molar ratio of methyl formate to oil, the amount of catalyst and the duration of the process was created. The following conditions were determined in which the highest yield of rapeseed oil methyl esters was obtained: molar ratio of methyl formate to oil 40:1, process duration 60 h and 14.57% of catalyst Lipozyme TL IM from the amount of oil. Under these conditions, an 81.79% yield of rapeseed oil methyl esters was obtained. Comparative studies of the physical and chemical properties of the product obtained during the interesterification process were performed and their compliance with the requirements of conventional biodiesel standard EN 14214 was evaluated.

Evaluation of Particulate Matter (PM) Emissions from Combustion of Selected Types of Rapeseed Biofuels

The manuscript describes the results of an experimental study of the level of PM (particulate matter) emissions arising from the combustion of two selected types of biomass (i.e., rapeseed straw pellets and engine biofuel (biodiesel, FAME)), which were derived from rapeseed. The PM emissions from the combustion of biofuels were compared with those obtained from the combustion of their traditional counterparts (i.e., wood pellets and diesel fuel). Both types of pellets were burned in a 10 kW boiler designed to burn these types of fuels. The engine fuels tested were burned in a John Deere 4045TF285JD engine mounted on a dynamometer bench in an engine dyno, under various speed and load conditions. A Testo 380 analyzer was used to measure the PM emission levels in boiler tests, while an MPM4 particle emission meter was used in the engine tests. The combustion (under rated conditions) of rapeseed straw pellets resulted in a significant increase in PM emissions compared to the combustion of wood pellets. The PM emissions during the combustion of wood pellets were 15.45 mg·kg−1, during the combustion of rapeseed straw pellets, they were 336 mg·kg−1, and the calculated emission factors were 44.5 mg·MJ−1 and 1589 mg·MJ−1, respectively. In the engine tests, however, significantly lower particulate emissions were obtained for the evaluated biofuel compared to its conventional counterpart. The combustion of rapeseed oil methyl esters resulted in a 40–60% reduction in PM content in the exhaust gas on average for the realized engine speeds over the full load range compared to the combustion of diesel fuel.

Green water-dispersible coarse powder nano-formulation for allelopathic leaf extract of Mikania micrantha Kunth ex H.B.K. in controlling the rice weed Echinochloa colona (L.) Link

Plant extracts originated from an exotic species, Mikania micrantha Kunth ex H.B.K. have shown appreciable phytoinhibitory activities against a rice weed, Echinocloa colona (L.) Link. In spite of that, the glutinous extracts exhibit poor physicochemical properties preventing it from delivering efficiently and for ease of application. This research study aimed to formulate the leaf extract of M. micrantha with pre-emulsions and lignocellulosic coarse powder for the sake of ameliorated bioefficacy of the extract via nano-delivery system and improved product handling. Three pre-emulsions were developed using rapeseed oil methyl esters (ROME) and disparate bisurfactant mixtures including polyalkoxylated fatty alcohol (PAFA)-alkyl sulfonate (AS), PAFA-cocamidopropyl betaine (CB) and PAFA-alkyl polyglucosides (APG). The pre-emulsions were incorporated with leaf extracts containing the phenolic allelochemicals. The pre-emulsified extracts were loaded onto mercerized lignocellulose by solvent percolation and evaporation (SPE) technique produced the formulated water-dispersible coarse powders, WDP-F1, WDP-F2 and WDP-F3. A non-formulated extract was prepared into water-dispersible powder, WDP-EX for quality control. The results show greater water absorption by the formulated powders in prolonged duration of 7 days exerted the release of higher total amount of phenolic compounds (63.66–86.52%) than the phenolics amount released from the non-formulated powder (41.98%). Transmission electron microscopy (TEM) revealed the formulated extracts exhibited particles release in regular patterns from three dimensional networks and gigantic vesicles, unlike the non-formulated extract liberated uneven particles from disordered aggregates. The particles released from the formulated powders displayed low mean sizes (87.56–103.27 nm) in monodisperse range (PDI = 0.180–0.203). In opposition, non-formulated particles indicated larger mean size (423.93 nm) and polydisperse (PDI = 0.550). In the glasshouse study, the formulated powders promoted significantly higher inhibitions of germination, shoot height, fresh weight and dry weight of E. colona than non-formulated powder and non-treated weedy control. Moreover, the paddy seedling growth and grain yield treated with the formulated powders were statistically equivalent (p = 0.05) to treated with a commercial formulation, Satunil® and weed-free non-treated control. These valuable outcomes genuinely reflected the inspirational use of green water-dispersible coarse powder in the formulation of natural products in fostering the sustainable development of crop protection products.

Application of thermogravimetric analysis method for the characterisation of products from triglycerides during biodiesel production

In this present work, thermogravimetric analysis (TGA) was used to study the thermal degradation of a range of lipids and lipid-derived compounds associated with the production of biodiesel. Thereafter, the procedure was used to successfully quantify the compounds of three process streams from a biodiesel plant. Relevant organic chemicals involved in biodiesel production chemistry, including glycerol, oleic acid (fatty acid), palmitic acid (fatty acid), rapeseed oil (model triglyceride) and fatty acid methyl esters (FAMES) have been studied to determine their volatilisation/thermal degradation patterns. The developed method was then applied for the quantitative characterisation of three samples from a 3-stage biodiesel production plant, including two in-process samples and the final biodiesel product. The method was able to clearly distinguish between two main sets of compounds namely, early - mid volatiles (glycerol, fatty acids and fatty acid methyl esters) and late volatiles (incompletely converted and unreacted triglycerides). In addition, the FAMES in the industrial samples were extracted into petroleum ether and analysed by gas chromatography - mass spectrometry (GC/MS), with good agreement between the two analytical methods. For instance, GC/MS analysis showed that the three industrial samples contained 31.2 ± 0.1 wt%, 60.6 ± 0.2 wt% and 91 ± 0.53 wt% of FAMES, respectively. Similarly, the TGA method gave the FAMES contents of the three samples as 33.9 ± 0.4 wt%, 57.8 ± 0.2 wt% and 85.3 ± 0.52 wt%. This study shows that TGA is a fast and simple method for accurately monitoring the triglyceride conversion stages and the purity of the final product during biodiesel production, without the need for extensive sample preparations and expensive standard solutions.

The influence of bio-fuels on the injection and combustion processes in a diesel cylinder

Introduction (statement of the problem and relevance). The need for vehicles motor fuels is growing from year to year. Limited oil resources lead to the need to replace them with alternative ones. The necessity to find a solution of the problem is also encouraged by the current unfavorable environmental situation. The possibility of using alternative fuel resources in existing engines requires the study of their influence on various aspects of engine operation, including the process of fuel supply and combustion in the engine cylinder.The purpose of the current research was to obtain the characteristics of fuel supply and combustion in a diesel engine operating on methanol and methyl ester of rapeseed oil.Methodology and research methods. As an object of study, a tractor diesel engine with a dimension of 2Ч 10.5/12.0 air-cooled with volumetric mixing was chosen. The characteristics presented in the work were taken in the nominal mode at the crankshaft speed n = 1800 rpm and the average effective pressure in the cylinder pe = 0.588 MPa, as well as in the maximum torque mode n = 1400 rpm, pe = 0.594 MPa. Pilot fuel supply in all modes was constant and fixed. The fuel injection advance setting angles were also constant and amounted 34° of the crankshaft rotation to the top dead center for each of the fuels.Scientific novelty and results. The article considered the bench tests results of a diesel engine operating on methanol and rapeseed oil methyl ester in two characteristic modes. The indicators of fuel supply and combustion process in the diesel cylinder have been presented. The analysis of these indicators allowed determining the influence of the fuel supply process on the combustion characteristics in the engine.The practical significance lies in the possibility of using the obtained results to improve the operation of diesel engines on alternative renewable fuels.

Comparison of the Combustion Process Parameters in a Diesel Engine Powered by Second-Generation Biodiesel Compared to the First-Generation Biodiesel

The use of biofuels to power compression–ignition engines makes it possible to reduce emissions of certain harmful components of exhaust gases. The purpose of this study was to determine the influence of second-generation biofuels on the course of indicator graphs and heat release characteristics of the Perkins 1104D-44TA compression–ignition engine. For comparative purposes, the same tests were carried out by feeding the engine with first-generation biofuel and diesel fuel. Babassu butyl esters (BBuE) were used as the second-generation biofuel. The second fuel was a first-generation biofuel—rapeseed oil methyl esters (RME). Analysis of the results made it possible to draw conclusions about the effect of using 2nd and 1st generation biofuels on the parameters of the combustion process. When the DF engine was powered, the lowest fuel dose per work cycle was obtained. In the case of RME and BBuE fuels, it depends on the engine load. For low loads, higher consumption is for RME, and for higher loads, fuel consumption for BBuE in-creases most often. This is due to the lower calorific value of the esters. The results of these tests indicate that feeding the engine with BBuE and RME fuel in most loads resulted in higher maximum combustion pressures compared to feeding the engine with DF which may be directly related to the higher cetane number of these fuels compared to DF and the oxygen content of these fuels. Feeding the engine with BBuE and RME esters compared to DF did not result in large differences in the maximum heat release rates HRmax. However, the values of the first and second maximum heat release rates x1max and x2max, in addition to the type of fuel, are strongly influenced by the operating conditions, especially the engine load. Analyzing the combustion angles of 5, 10, 50, and 90% of the fuel dose, it can be seen that feeding the engine with BBuE and RME esters for most measurement points results in faster combustion of the fuel dose compared to DF.

The effect of natural deterioration on selected properties of rapeseed oil methyl esters

The article discusses the results of research into properties of rapeseed oil methyl esters of and diesel oil subjected to deterioration process at room temperature for 20 years. The heat of combustion and heating values have been measured in laboratory conditions using an automatic calorimeter. The results show a slight decline in energy properties, with a change of 3.45 % on average. An image analysis has been used to evaluate the effects of ageing and combustion quality to compare the two fuels. The main purpose of research on rapeseed oil methyl esters in relation to diesel oil was to determine the energy properties of the tested fuels, i.e., the heat of combustion and the heating value. The side aims of research were to determine selected functional properties of the tested fuels.Changes in density, kinematic viscosity, acid value and water content at the beginning and end of the experiment have also been examined. Deposits formed after combustion in a calorimetric bomb in crucibles and on the injector nozzles in a self-ignition engine have been examined with the use of the weight method and images analysis.After a long period of storage, density, and acid number of rapeseed oil methyl esters have been slightly changed, while kinematic viscosity and water content increased significantly to exceed the limit values. The acid value of diesel oil increased by 75% as a result of natural deterioration.

Greenhouse gas emissions from rapeseed oil ethyl and methyl esters

To ensure the sustainability of the biofuel chain, regulatory criteria and greenhouse gas (GHG) emissions targets have been defined by various legislative frameworks. This study used five emission allocation principles to determine the GHG emission reduction factors for rapeseed methyl ester (RME) and rapeseed oil ethyl ester (REE): total GHG emissions from the biorefinery; energy contained in the product (Eno); for each sub-process, emissions from the process inputs were allocated based on the energy from the process outputs; the avoided energy supply-related emissions were deducted using the energy allocation model described in this work; and all GHG emissions from rapeseed production were allocated to biodiesel, glycerin, and rapeseed meal. RME yields a more significant reduction in hydrocarbon emissions (by 74%) compared to REE (53%). The use of pure RME reduces CO emissions by 5.7% compared to fossil diesel fuel. The use of pure REE reduces CO emissions by 7.2%. The smoke density decreased by 68.4% (RME) and 72.6% (REE) compared to that measured for fossil diesel fuel. Hence, the amount of nitrogen and carbon oxides emitted and the smoke density of rapeseed oil ethyl ester have a lower negative impact on the environment compared to rapeseed oil methyl ester.

Method of Evaluation of Materials Wear of Cylinder-Piston Group of Diesel Engines in the Biodiesel Fuel Environment

This article concerns the method of material consumption assessment of the cylinder-piston group of diesel engines in the biodiesel environment. The obtained experimental dependences of the wear coefficients on the example of the tribounit cylinder liner and the piston ring can be used to forecast the resource use during operation under specific conditions of the engine and the environment as a whole. The article systematizes the types of biofuels, depending on the type of raw materials from which they were made, taking into account the process and application. The physical and chemical aspects of the catalysts used for biofuels were indicated. The applied experimental methods for tribological wear of the piston-cylinder pair were analyzed. B70 biodiesel was used in the research, i.e., 70% mineral diesel oil and 30% methyl esters of rapeseed oil. Experimental tribotechnical studies of the influence of biofuels on the behavior of various materials have shown that when using this type of fuel, it is necessary to replace the materials from which some parts of the cylinder-piston group are made. To solve this problem, research has been carried out on a specially designed friction machine. The novelty in the article concerns the association, based on the literature, of hydrogen consumption causing material wear in friction contacts. The mechanism of the interaction of various construction materials during such friction has been disclosed.

High pressure thermophysical characteristics of butyl caprate and butyl laurate as fully biorenewable components of biodiesel fuel

The butyl-based fatty acid esters can be considered as fully biorenewable components of biodiesel fuel due to the possibility of synthesis from biobutanol and vegetable or animal oils. For this reason in this work high pressure thermophysical properties of butyl caprate (butyl decanoate) and butyl laurate (butyl dodecanoate) used for optimization spray characteristics in diesel injection systems are studied. The speed of sound was measured at temperatures from 293 to 318 K and pressures from 0.1 to 101 MPa. The speed of sound, density, isobaric heat capacity, viscosity, surface tension were measured under atmospheric pressure and at the temperatures from the range of 273 to 363 K. The effect of temperature and pressure on density, isentropic and isobaric compressibilities, isobaric heat capacity, and isobaric thermal expansion was determined by the acoustic method. The results obtained show that differences between density and isentropic compressibility of esters can be compensated by temperature and/or pressure. Comparison of thermophysical properties of butyl caprate and butyl laurate with characteristics for diesel, biodiesel composed of fatty acids methyl esters of rapeseed oil, neat methyl and ethyl esters shows that they can be considered as promising fuel additives in this regard.

UTILIZATION OF OPERATIONAL PARAMETERS MONITORING TO ECONOMICAL AND SAFETY DRIVE OF VEHICLES

The paper is focused on the issue of measuring the amount of fuel in the tank of truck, construction and agriculture machine. The gradual expansion of of the share of the biocomponent in diesel fuel results in greater measurement errors via the capacitive probe in the fuel tank. The proposed solution, which uses three electrodes leads to increased accuracy in measuring of the amount of fuel in the tank. According to standard EN 590, the measurement error of the new capacitive probe is only 1.5% when using diesel. The highest measurement error 4% is achieved when using neat rapeseed oil methyl ester. The previous solution of the capacitive probe when using diesel fuel according to EN 590 achieved a measurement error of 2.5%, but it increased significantly with the proportion of rapeseed oil methyl ester up to 70% when using neat rapeseed oil methyl ester. The new capacitive probe concept with two positive electrodes and higher accuracy can be used to evaluate driving style towards economical and environmentally friendly driving. It is also possible to focus on safe driving style of drivers using other operating parameters. The aim of the paper is to compare the capacitive probe with one and two positive electrodes and demonstrate their use in evaluating the driving style of drivers.

Possibility of Using Commercial Hydrated Lime as a Catalyst for Rapeseed Oil Methanolysis

In this research, the possibility of using Ca(OH)2 in the form of commercial hydrated lime as a catalyst for the methanolysis of refined rapeseed oil was evaluated. Characterization of unused catalyst was performed by SEM-EDS, laser diffraction, XRF, BET, XRD and TG/DTG methods, and vegetable oil was analyzed for physicochemical characteristics. Within methanolysis, the effects of catalyst loading, reaction temperature and reaction time on methyl ester yield, density and viscosity of biodiesel, as well as the possibility of catalyst reuse were investigated. The obtained results showed that hydrated lime is an efficient catalyst for transesterification of vegetable oil, whereby the use of 3 wt% of catalyst relative to oil weight, at temperature 60℃ and mixing rate 1000 rpm after 120 min of transesterification reaction achieved a yield of methyl esters 98.76%. With three reuses of hydrated lime, without intermediate washing and regeneration procedures, the yield of rapeseed oil methyl ester remained above 90%.

Injection and Combustion Analysis of Pure Rapeseed Oil Methyl Ester (RME) in a Pump-Line-Nozzle Fuel Injection System

This work suggests an interpretation to the quantitatively higher formation of NOx in a compression ignition (CI) engine when fueled with pure biodiesel (B100). A comparative study about the use of rapeseed oil methyl ester (RME) and diesel fuel mixtures on injection timing, in-chamber pressure, heat release rate, and NOx emissions were carried out using a diesel engine equipped with a pump-line-nozzle injection system. Such engines are still widely adopted mainly in agriculture, as the fleet of agricultural machinery is particularly old (often over 20 years) and the use of biofuels can reduce the environmental footprint of the sector. This work aims to supply some general explanations and figures useful to interpret the phenomena occurring within the fuel line and in the combustion process when using biodiesel, as well as in engines with different construction characteristics and fueling systems. Given the contradictory results available in the literature, the so-called “biodiesel NOx effect” cannot be explained solely by the different physical properties of biodiesel (in particular, a higher bulk modulus). Experimental results show that, with the same pump settings, the start of injection with the RME is slightly advanced while the injection pressure values remain almost the same. With the RME, the pressure in the injection line increases faster due to its greater bulk modulus but the pressure rise starts from a lower residual pressure. The start of combustion takes place earlier, the heat release during the premixed phase is steeper, and a higher peak is reached. The NOx emissions with the RME are at least 9% higher when compared to mineral diesel fuel. The greater amount of the RME injected per cycle compensates for its minor lower heating value, and the brake torque at full load is similar to the two analyzed fuels. Finally, a variation of the pump line timing is evaluated in order to assess the effect of the delay and the advance of the injection on the performance of the engine and on the emissions. A viable and simple solution in the variation of the injection strategy is suggested to counterbalance the biodiesel NOx effect.