Reduction Of Hydrocarbon Emissions Research Articles

Investigation on the hydrocarbon adsorption performance enhancement of the ZSM-5 zeolite with different Si/Al ratio in the cold start process of the gasoline engine

In response to the issue of hydrocarbon emissions during the cold start process of gasoline engines, a hydrocarbon catcher coated with ZSM-5 zeolite was manufactured. The post-treatment system of the prototype vehicle was modified to install the hydrocarbon catcher, and cold start experiments on the vehicle under World Light-vehicle Test Cycle (WLTC) conditions were conducted. The experimental results showed that the hydrocarbon emissions in the low-speed stage of WLTC were much higher than those in other stages. In the early stages of cold start, the hydrocarbon catcher can reduce hydrocarbon emissions by up to 61 %. The analysis results of engine emissions showed that the content of various hydrocarbon components during cold start was: 60.1 % butene, 13.6 % acetylene, 11.3 % propylene, 7.3 % ethylene, 7.1 % acetaldehyde, and 0.6 % other components. Further molecular simulation studies were conducted on zeolite of different types and Si/Al ratios. The results showed that the adsorption of hydrocarbons on pure Si-MFI and -FER zeolites were less affected by H2O and CO2, making them ideal hydrocarbon capture materials. Al substitution introduced compensating cations into zeolite, which increased the adsorption capacity of H2O, CO2, and C2H4O with polar functional groups. Reducing the degree of Si/Al substitution is beneficial for hydrocarbon adsorption.

Performance and Exhaust Emissions from Diesel Engines with Different Blending Ratios of Biofuels

Fossil fuel extraction and utilization are associated with several environmental issues. This study examined how altering the blending proportions of mixed diesel/biodiesel/n-butanol fuels impacts combustion. Additionally, it delved into the functioning of diesel engines when utilizing these blended fuels as well as conventional diesel. A three-dimensional fluid dynamics simulation was constructed and corroborated against test outcomes obtained at 25%, 50%, 75%, and 100% loads. The findings indicated that the n-butanol addition enhanced the indicated thermal efficiency. At a 100% load, D70B30 (70% diesel + 30% biodiesel), D70B25BU5 (70% diesel + 25% biodiesel + 5%N-butanol), D70B20BU10, and D70B10BU20 exhibited 4.76%, 5.75%, 6.79%, and 8.71% higher indicated thermal efficiency values than D100 (100% diesel), respectively. The introduction of butanol enhanced the combustion environment within the combustion chamber. Compared with pure diesel, all blended fuels reduced hydrocarbon and carbon monoxide emissions across various loads. The blended fuels showed significant reductions in hydrocarbon emissions of 1%, 4%, 6%, and 15% compared with that of diesel under the 25% load, respectively.

EXPERIMENTAL INVESTIGATION OF THE PERFORMANCE OF A FOUR-STROKE CI ENGINE UTILIZING DIESEL, LIZA OIL, AND BUTYLATED HYDROXYTOLUENE BLENDS

Amidst the depletion of natural resources, the surge in petroleum fuel costs and the impending scarcity of transportation options have prompted a quest for viable alternatives. One promising avenue is the exploration of vegetable oils, such as Liza oil, blended with Butylated Hydroxytoluene (BHT) at a 2% concentration. To optimize the economics of biodiesel production, researchers are delving into continuous transesterification and glycerol recovery from by-products. In this study, the performance and emissions of distinct blends of diesel and Liza oil with the additive (B10, B20, B30, B40, and B50) are systematically evaluated under various loads and at constant speeds. Encouragingly, the Liza oil blend outperformed diesel, with B30 and B40 blends exhibiting the highest mechanical and brake thermal efficiency. Notably, the B10 and B30 blends demonstrate the lowest and highest brake-specific fuel consumption, respectively. Furthermore, the B20 Liza oil biodiesel displays reduced hydrocarbon emissions compared to conventional diesel fuel. These findings shed light on the promising potential of Liza oil blends as a favorable alternative in the landscape of sustainable fuels.

Effects of nanoadditives on the performance and emissions of rapeseed biodiesel in an insulated piston diesel engine.

Energy consumption and management have emerged as crucial production functions because of the high cost of energy. Since the total consumption of fossil fuels like diesel has increased proportionally to the expansion in demand for power generation, industry, and transportation services, researchers have long been interested in constructing a more energy-efficient engine. With its improved efficiency, reduced fuel consumption, and fewer emissions, the application of nano-coating technology to engine components has become more popular in recent years. This study involved the application of a thermal barrier coating (TBC) using zirconia on the test engine piston. The aim of this research is to examine the impact of aluminium oxide nano-additives in rapeseed biodiesel blends on the performance of a diesel engine with a thermal barrier-coated piston. The four test fuels were prepared using 20% and 40% blends of rapeseed biodiesel with and without the addition of aluminium oxide at 25 ppm and 50 ppm. The full factorial design methodology was employed to examine the influential factors, specifically the rapeseed blend ratio and aluminium oxide concentration, in order to enhance performance and reduce emissions. The blends of RSB20AO25 and RSB20AO50 showed significant results on energy consumption and emissions. The RSB20AO50 blend performed with a 5.4% increase in brake thermal efficiency and a 6.5% reduction in fuel consumption compared with standard diesel. Similarly, blends of RSB20AO25 and RSB20AO50 show 6% and 11% reductions in carbon monoxide and 5.2% and 9.5% reductions in hydrocarbon emissions.

Numerical investigation of performance, combustion, and emission characteristics of spark-ignition engine fuelled with compressed natural gas and hydrogen

The combustion of gasoline engines running on blends of compressed natural gas and hydrogen fuels was investigated using the quasi-dimensional and two-zone model. This model could investigate and predict the combustion characteristics, emissions, and performance parameters of petrol engines using MATLAB software. The impact of hydrogen inclusion to compressed natural gas on the cylinder temperature, pressure, cumulative work done, and heat transfer related to compressed natural gas was investigated. The engine’s thermal efficiency and output power were increased while specific fuel consumption was decreased when hydrogen was blended up to 20%. The highest decline in specific fuel consumption of 20% hydrogen was 25.1% for compressed natural gas. The torque values are 4.25, 4.34, 4.42, 4.51, and 4.60 N·m for compressed natural gas, hydrogen with compressed natural gas HCNG 5%, HCNG 10%, HCNG 15%, and HCNG 20%, respectively, at rated speed of 2500 r/min. The peak decreases in peak cylinder temperature and pressure for HCNG 20% compared to compressed natural gas are 5.9% and 5.2%, respectively. For HCNG 20%, the greatest cylinder pressure, temperature, and cumulative work done were 7.9 MPa, 2309.97 K, and 190.88 J, respectively. NO x emissions were increased for hydrogen-compressed natural gas blends but hydrocarbon emissions were decreased. In comparison to compressed natural gas, the highest hydrocarbon emission reduction is up to 2.64% for HCNG 20%. The model's validity was examined in comparison to the findings from the literature and the Diesel RK program. The results show that the MATLAB code is appropriate. Several alternative fuels can be used using this mathematical model.

Optimizing Biodiesel Blend Performance with Nano Additives in Diesel Engines for Sustainable Environmental Impact

Biodiesel, a sustainable alternative to traditional petroleum-based diesel, can be derived from various sources such as vegetable oils, animal fats, and recycled cooking oils. Its production and use have gained momentum due to its potential to reduce greenhouse gas emissions and diminish our reliance on fossil fuels. The combustion of fossil fuels contributes significantly to climate change and various forms of pollution. In India's agricultural sector, the production of biodiesel from non-edible plant oils has witnessed a surge in popularity. However, the current supply of these biodiesels falls short of meeting the growing demand for fossil fuels. To address this challenge, a novel biodiesel formulation using non-edible oils has been developed. This study aims to create an innovative biodiesel blend comprising 50% cottonseed biodiesel, 50% rapeseed biodiesel, and diesel with the addition of cerium oxide. The results obtained with CR20N50 indicate a substantial 15–18% reduction in fuel consumption, a notable 12–22% decrease in carbon monoxide emissions, and a significant 13–20% reduction in hydrocarbon emissions compared to conventional diesel fuel.

Effective utilization of cashew nut shell pyro oil blended with optimum amount of Al2O3 and TiO2 nanoparticles in DI engine

The present research activity's major objective is to improve the performance and emission characteristics of diesel engines that burn pyro oil and cashew nut shell nanoparticles. This work identifies the nanoparticles that should be added to cashew nut shell pyro oil to allow it to be utilized efficiently in compression ignition engines. In this experiment, the two nanoparticles, Al2O3 and TiO2, were mixed with cashew nut shell pyro oil. For testing purposes, nanoparticles were combined with cashew nut shell pyro oil at various concentrations, including 150 and 200 ppm. The criterion for picking the best combination was stability. To improve the optimal performance of the nanoparticle-blended oil, the cashew nut shell pyro oil was emulsified. The nanoparticles, which also act as an enhancing agent, speed up the combustion process. The combination of pyro oil, cashew nut shell emulsion, and nanoparticles improved performance and reduced emissions. The brake thermal efficiency values for 200 ppm Al2O3 and TiO2 mixed emulsified cashew nut shell pyro oil were 29.6% and 29.4%, respectively, whereas the values for diesel and cashew nut shell pyro oil were 31.6% and 29.8%. When comparing cashew nut shell pyro oil to oil with 200 ppm Al2O3 and TiO2, the smoke value was found to be reduced by 58.8% and 56.7%, respectively. It was discovered that cashew nutshell pyro oil with 200 ppm Al2O3 and TiO2 had 35.3% and 34.96% reduced hydrocarbon emissions respectively.

Performance Emission and Combustion Characteristics of Ethanol Hydrogen Blends at MBT Spark Timing on Multi-cylinder SI Engine

Alternative fuels are the need of the current situation as conventional fuels are depleting very quickly and causing increase in amounts of pollution. Hydrogen as a clean fuel with Higher Calorific Value plays important role in increasing combustion characteristics. When compared with the performance of ethanol as a fuel, ethanolhydrogen blends have demonstrated a 5% increase in power production, 15% reduction in hydrocarbon emissions, and 12% reduction in carbon dioxide emissions. All tests are conducted at speed of 2500, 3000, 3500, 4000, and 4500 rpm with the Wide-Open-Throttle (WOT) condition. CO & HC emissions are reduced using ethanol, whereas hydrogen addition enhanced the decreased power output, higher brake-specific fuel consumption and in cylinder pressure.
 Keywords: Emission, combustion, ethanol, hydrogen, SI engine, alternate fuels, conventional fuels, renewable energy sources, MBT spark timing, NOx emissions, nitrogen, Maximum Brake Torque

Experimental study of a dual-fuel spark-assisted compression ignition engine with polyoxymethylene dimethyl ether and methanol as fuels

Polyoxymethylene dimethyl ethers (PODE) and methanol are promising alternative fuels for internal combustion engines, offering emission reduction and compatibility with existing engine combustion technologies. They can be chemically synthesized, providing a renewable and clean energy source for sustainable transportation. Additionally, dual-fuel spark-assisted compression ignition (SACI) is an advanced combustion mode that offers precise control of the combustion. However, there is limited research on dual-fuel SACI based on PODE and methanol, and the understanding of its multi-stage combustion, the cross-effects of multiple parameters, and the transition between ignition and compression ignition are still unclear. In this study, a modified gasoline engine was used to investigate the combustion characteristics of a dual-fuel SACI engine. The engine was fueled with direct injection PODE and port injection methanol. The combustion process was examined with a focus on the cooperative control of multiple parameters. The effects of the mass ratio of PODE, spark ignition timing, and start of injection timing were analyzed. The results demonstrated the presence of multiple heat-release stages during dual-fuel SACI combustion, involving both compression ignition and flame propagation ignition. An optimal interval between the start of injection timing and spark ignition timing was observed, leading to high brake thermal efficiency. This interval facilitated the formation of a highly reactive mixture during ignition, enabling efficient ignition of methanol by PODE. At a brake mean effective pressure of 0.8 MPa, a brake thermal efficiency of 44% was achieved with a 75% methanol ratio. Additionally, by appropriately increasing the mass ratio of PODE and advancing the start of injection timing, a significant reduction in hydrocarbon emissions was observed, albeit with a slight increase in nitrogen oxide emissions. These findings provide support for low-carbon operation of engines.

Effective utilization of biodiesel blends with nano additives on diesel engine towards eco-sustainability

The sustainable fuel known as biodiesel can be produced from either vegetable oils, animal fats, or even recycled cooking oils. It has the potential to cut greenhouse gas emissions and lessen our dependence on oil when compared to traditional diesel derived from petroleum. Burning fossil fuels releases greenhouse gases, which are a key contributor to climate change as well as other pollution. In India’s agriculture industry, making biodiesel from plant sources, especially oils that can’t be eaten, has gained a lot of popularity in recent years. In addition, there are not enough of these biodiesels on the market to match the surging demand for fossil fuel. A new biodiesel composition that can be used in diesel engines is made from non-edible oils. The development of a new combination of biodiesel is crucial in order to keep up with the surging demand for fossil fuels. The purpose of this study is to create a novel biodiesel blend of 50 % cottonseed biodiesel and 50 % rapeseed biodiesel and diesel with cerium oxide. The results of CR20N50 show a 15–18 % reduction in fuel consumption, a 12–22 % reduction in carbon monoxide emissions, and a 13–20 % reduction in hydrocarbon emissions compared with base diesel.

Experimental and numerical study of using of LPG on characteristics of dual fuel diesel engine under variable compression ratio

In this work, an experimental and numerical investigation are carried out to study the impact of adding Liquefied Petroleum Gas (LPG) on the characteristics of diesel engine. New injection control system (ICS) is designed to manage an LPG injector on intake manifold a single-cylinder diesel engine. The engine test rig is powered with traditional diesel fuel to generate the base line data for comparison. Different conditions of load (0%, 25%, 50%, 75%, and 100%) in terms of brake power with three compression ratios of 14.5, 15.5 and 16.5 at constant engine speed of 1500 rpm. LPG is tested in four rates (5 L/min, 10 L/min, 15 L/min, and 20 L/min). The numerical analysis is performed with the help of Diesel-RK simulation software. The multizone combustion model is adopted. Same operating conditions in the experimental work are followed in the numerical simulation. The obtained results revealed that brake thermal efficiency (BTE) and exhaust temperature are reduced while brake specific fuel consumption (BSFC) is increased as the rate of LPG increased. Inducting LPG with (5,10,15,20) L/min reduced carbon monoxide (CO) by 16.6%, 14.7%, 20.3%, and 18.8% respectively. The maximum reduction in hydrocarbon emission (HC) is 8% at the rate of 15 L/min compared to diesel. The volumetric efficiency and NOx emissions are decreased with the use of LPG. As the compression ratio increases, BTE increases and BSFC decreases because of increasing combustion temperature and pressure which decreases delay period, ignites fuel fast and produces more power in small time. The impact of increasing compression ratio reported significant reduction in, CO, HC while NOx are increased. The experimental findings are compared to the results of the Diesel-RK software, as well as with the results of other researchers and good harmony among them is noticed.

Experimental investigation of the effects of preheating temperature on low-temperature cold start performance, emissions and energy conversion of diesel-electric hybrid

Low compression end temperatures, high heat loss, and large resistance torque cause difficulty in starting conventional diesel engines at extremely low temperatures. The diesel-electric hybrid is equipped with high-capacity battery, which can support high-energy-consuming preheating measures to improve low-temperature cold-start performance. However, only a few studies have been conducted on the effect of preheating on the low-temperature cold-start performance of diesel-electric hybrid. In this study, the influence of different preheating temperatures on the performance, emissions, energy consumption, and conversion of a diesel-electric hybrid was experimentally investigated by designing an environmental simulation system and a preheating system. The results showed that intake air preheating consumed less energy and maintained a high energy conversion efficiency. As the intake air temperature increased, the combustion conditions improved, increasing the indicated mean effective pressure and enhancing combustion stability. However, intake preheating was invalid when the ambient temperature was below 244 K because of the high heat loss and large resistance torque. As the coolant temperature increased, the ignition delay period was significantly reduced, allowing the maximum pressure in the cylinder to increase. The corresponding position became closer to the top dead center, resulting in a steady increase in the speed rise rate, a reduction in hydrocarbon emissions from 1403 ppm to 298 ppm, and a reduction in opacity from 85% to 43%. The increase in the lubrication temperature mainly decreased the resistance torque, resulting in a reduction in the drag time and rise time of 0.37 s and 2.21 s, respectively. At 233 K, the minimum energy consumption of the combined preheating of the coolant and intake air was 2557 kJ. In contrast, the combined preheating of the lubricant and intake air was only 379 kJ, but the emission performance of coolant preheating was better than that of lubricant preheating. This result could be considered as the constraint boundary for optimizing the total equivalent energy consumption and is useful for optimizing the preheating strategy and development of diesel-electric-hybrid low-temperature thermal management.

Application of nanomaterials for emission reduction from diesel engines powered with waste cooking oil biodiesel

Abstract Diesel engines that predominantly run on fossil-based diesel fuel emit harmful emissions. Biofuels such as biogas and biodiesel are potential alternatives. However, many biofuels have poor heating values and supply inconsistencies. The use of nanoparticles (NPs) offers an appealing alternative for enhancing the combustion and emission reduction. This study aimed to improve the emission performance of biodiesel produced from waste cooking oil biodiesel (WCOB) by adding titanium oxide (TiO2) NPs. Tests were conducted in the diesel-powered engine at varying load levels using fuel mixtures of B1 (100% diesel), B2 (80% diesel + 20% WCOB) and B3 (80% diesel + 20% WCOB with the addition of 200 mg/l TiO2 NPs). In comparison with the diesel mode, the average reduction in carbon monoxide emissions was 8.92% for the B2 blend and 25% for the TiO2 NP-based B3 blend. For the B2 blend and TiO2-based B3 blend, the mean reduction in hydrocarbon emissions was 5.6 and 16.6%, respectively, when compared with diesel mode. When comparing B3 blends with B2 blends, the average reduction in nitrogen oxide emissions was 3.75%. In conclusion, adding NPs to engine fuel is a viable solution for reducing emissions.

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.

State of art review of algal biodiesel and its blends influence on performance and emission characteristics of compression ignition engine

The current scenario, ever ending increase in depletion rate of petro-diesel and eventually their socio-economic impacts, strongly urges to invent appropriate substitute to petro-diesel. Profound research in the field has been carried out till time which is still continuing for investigating even more possible and probable way outs. In this context, the evaluation of the performance parameters of internal combustion engine is the essential step to ascertain the effective and appropriate fuel and its blends. This paper focus on extensive review of often discussed performance parameters such as break specific fuel consumption, break thermal efficiency and brake power. To widen the assortment of information in this field, the state of art review of the emission characteristics of Compression Ignition machine using algal biodiesel as a fuel has been recited through this survey. For evoking more precise knowledge of this review, the variety of fuel and engine type used for experimentation is thoroughly reviewed, analyzed and explained. It was found in review that there is an increase in brake power by 1%–20%, brake specific fuel consumption by 0.9%–13.90% and brake thermal efficiency from 1% to 27.65% which are in adoptable range. The emissions such as carbon monoxide and dioxides are found to be reduced considerably along with reduction in hydrocarbon emissions. The only exemption of oxides of nitrogen which found to be increase. Finally, it can be underlined that algae and its blends) characteristics were compatible with petroleum diesel and performance and emission parameters are in close proximity of diesel so, algal biodiesel and its blends can be used as diesel engine fuel without any modification in existing diesel engines. Considering the state of art review on this less explored topic, along with blends preparation, investigating physiochemical properties of blends and the impact of small proportion of algal biodiesel blends on performance and emission of compression ignition engine could be carried out.

Impact of different magnetorheological fluid compositions on poppet valve profile polishing

Precise finishing of the poppet valve profile will make it perfectly fit on its seat in the aerospace gas propulsion engine to reduce hydrocarbon emissions. Nano-finishing of poppet valve narrow profiles is a particularly challenging job. This article reports on the uniform polishing of the poppet profiles using a novel magnet fixture used in the rotational-magnetorheological fluid-based finishing (R-MRFF) method. The precise finishing of the Nickel aluminium bronze (BS1400 Gr. AB2) (excellent corrosion resistance and bearing properties) poppet profiles is done through various compositions of magnetorheological polishing (MRP) fluid. After performing the experiments, surface characterization and material compositions are outlined for both polished and unpolished poppet profiles. Magnetostatic simulation is also performed to observe the distribution of magnetic flux density along poppet valve profiles. This magnetostatic analysis will help in understanding the finishing mechanism properly. Ultrafine surface roughness (Ra = 21.3 nm) at poppet profiles are obtained using an MRP fluid of Type ‒ 2. All manufacturing defects are almost removed from the poppet valve profiles.

РЕЗУЛЬТАТЫ ОПЫТНО-ЭКСПЛУАТАЦИОННОГО СЖИГАНИЯ ТОПЛИВНО-ВОЗДУШНОЙ СМЕСИ В БЕНЗИНОВОМ ДВУХТАКТНОМ ДВИГАТЕЛЕ 1Д 4,5/3,5, ОСНАЩЕННОМ ПОРШНЕМ, МОДИФИЦИРОВАННЫМ КАТАЛИТИЧЕСКИМИ МАТЕРИАЛАМИ

The paper presents the results of testing of silumin-based catalysts in CO oxidation reactions. High catalytic activity was shown by both palladium-containing catalysts and catalysts based on base metals. Based on the test data, 2 types of catalytic coatings were synthesized on the pistons of the 1D 4.5/3.5 engine. An effective reduction in the content of carbon monoxide and hydrocarbons in the exhaust gases of gasoline two stroke engines was shown. It is shown that the reduction of hydrocarbon emissions can reach up to 41.5%, and carbon monoxide emissions – up to 52.5% when using a modified piston instead of the original one.

Green Economy and Meat Processing–Future Prospects

This paper provides a brief overview of the possible strategies for reducing hydrocarbon emissions from the meat industry according to the Green Deal program of the EU in the next decades. An overview of emerging technologies (high-pressure processing (HPP), shock wave technology (SW), ohmic heating (OH) and pulsed electric field (PEF), cultured meat) that should reduce gas emissions is given, as well as methodologies that can be applied (labelling, sustainable cooking, product lifecycle management (PLM) and product data management (PDM) applications). Noticeably, most novel strategies draw the conclusion that we should go for lower consumption of meat, especially beef, and change habits to eat and prepare foods in energy and environmentally friendly ways, as well as apply the so-called “green” food declaration in the future. Transforming into a climate-friendly economy, protecting biodiversity, and reorienting the agri-food industry growth can contribute to creating greater resilience of society.

Effect of diesel injection strategy on performance and emissions of CH4/diesel dual-fuel engine

Methane/diesel dual-fuel combustion technology has the potential to reduce emissions of nitrogen oxides (NOx) and particulate matter (PM). However, this combustion mode still suffers from low thermal efficiency, high levels of unburned hydrocarbons (HC) and carbon monoxide (CO) emissions under low-load conditions. In the current study, experimental research was conducted to investigate the effect of diesel injection strategy, including single and split injections, on the performance and emissions of a methane/diesel dual-fuel engine. The experimental tests were carried out on a single-cylinder diesel engine at 1500 rpm under different engine load conditions. The results revealed that split injection strategy has a significant impact on the combustion of the dual-fuel engine. Moreover, the brake thermal efficiency increased by an average of 25.6 % compared to the single injection strategy at low load. Brake specific fuel consumption decreased by 20.4% with a pre-injection timing of 11°bTDC at 20% engine load. Further, the pre-injection strategy contributed to the simultaneous reduction of NOx and combustion noise with a slight reduction of HC emissions. Finally, the inclusion of early post-injection resulted in improved brake thermal efficiency. NOx emissions decreased slightly, by delaying the post-injection timing for low to medium loads.

SURFAKTAN UNTUK BAHAN BAKAR SOLAR DAN BIODIESEL

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