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This study focuses on the optimization of ultrasound-assisted oil extraction from Carica candamarcensis seed using response surface methodology. The process parameters considered were extraction time (30–60 min), ultrasound amplitude level (20–40%), and solvent to seed ratio (10–20 mL/g). These were varied as suggested by Box-Behnken experimental model. Optimum values of these process parameters were given by the regression model, with the corresponding extraction yield. The model was validated experimentally to ensure its reliability. Physicochemical properties and fatty acid compositions of the extracted oil were evaluated accordingly. Furthermore, the extracted oil was then converted into biodiesel via ultrasound-assisted transesterification, using potassium hydroxide as the catalyst. FAME contents of the produced biodiesel were measured using gas chromatography. In addition, physicochemical properties of the biodiesel were also determined accordingly. Hence, findings from this study would be beneficial in further exploration on the usage of Carica candamarcensis as a potential feedstock for biodiesel production.

With the growing research in bioethanol production focusing on green algae, studying the parameters during the hydrolysis that will influence the quality of the end product is important. In this case, the design of experiment (DoE) serves as a critical start especially in terms of considering the overall cost. This study compares the design DoE based on Central Composite Design (CCD) and Box-Behnken Design (BBD) in the hydrolysis stage in producing reducing sugar from Chlorella pyrenoidosa. With four employed parameters (i.e., feedstock loading, NaOH concentration, hydrolysis temperature, and hydrolysis time), using response surface methodology (RSM), 30 experimental runs were generated from CCD and 29 from BBD. As the employed factors between the two DoEs were examined, BBD was more preferable in meeting lower cost constrained.

A system combining ultrasound and infrared radiation was used to increase the chemical reactions between incompressible reactants by enhancing their mass transfers with the aim to reduce the energy usage and reaction time. In this study, biodiesel from RBO was produced via transesterification, and the process variables were optimized using the combination of ANN and GWO algorithm. Process parameters considered in this study are ratio of methanol to oil, catalyst concentration, and reaction time. Based on the ANN-GWO algoritm used, the optimum conditions for the process parameters were (1) methanol to oil ratio: 60%, (2) concentration of catalyst: 1 wt%, (3) time: 7.76 min, leading to the metyl ester yield of 98.16 wt%. The algoritm was verified by conducting a triplicate independent experiments using the suggested optimum values, resulting in an average methyl ester yield of 97.74 wt%. Subsequently, properties of rice bran biodiesel were compared to ASTM D6751 and EN 14214 standards, and the obtained values met both the standards.

The increase of motor vehicles results in a rapid increase in fuel supply and generates high emissions, which then affects the environment and human health in general. Replacement of nonrenewable fuels can be achieved by using alternative energy sources. Viewing fuel properties and production routes, biodiesel is deemed as one preferred alternative fuel for diesel engines. This work focuses on biodiesel production using waste cooking oil through a catalyst made of mixed multi-fruits’ peel ash and titanium dioxide nanoparticles through a transesterification process. Further, the produced biodiesel was used to evaluate the engine performance by analyzing brake thermal efficiency and brake-specific fuel consumption. Emission characteristics due to biodiesel combustion, namely carbon monoxide and nitrogen oxides, was our main focus in this study. Both engine performance and emissions levels were optimized through Taguchi L16 orthogonal array. Highest brake thermal efficiency of 36.19% was achieved by the influence of 450°C of calcination temperature, 30°C of reaction temperature, 4% of catalyst loading, and 3 hr time of reaction. The lowest brake-specific fuel consumption obtained is 0.23 kg/kWh by involving 300°C of calcination temperature, 60°C of reaction temperature, 4% of catalyst loading, and 5 hr time. The statistical analysis based on ANOVA shows that the studied parameters does contribute to the developed regression model. In emission analysis, calcination temperature greatly influenced both CO and NOx.

Sterculia foetida derived biodiesel is a potential fuel for a diesel engine. The Sterculia foetida biodiesel required a pre-refining process called degumming and an acid pretreatment process before converting them to methyl ester using the transesterification process. This study blended fuel from Sterculia foetida biodiesel and diesel with different volume ratios (5% to 30% of biodiesel blend with 95% to 70% diesel fuel). Sterculia foetida biodiesel and blended fuels met the ASTM D6751 and EN 14214 standards. The blended fuel is examined to obtain its influences on the performance and emission when operating at a diesel engine (1300 rpm to 2400 rpm). From the outcome, the engine performance of the SFB5 blend shows better performance than diesel fuel in terms of BTE (28.84%) and BSFC (5.86%). Artificial neural networks and extreme learning machines were employed to predict engine performance and exhaust emissions. The developed models gave excellent results, where the coefficient of determination is more than 99% and 98% for BSFC and BTE, respectively. When the engine is operated with SFB5, there is a significant reduction in CO, HC, and smoke opacity emissions by 8.26%, 2.08%, and 3.08%, respectively, and at the same time, an increase in CO2 by 3.53% and NOX by 22.39%. The comparison is made with diesel fuel. The extreme learning machine modelling is powerful for predicting engine performance and exhaust emission compared to artificial neural networks in terms of prediction accuracy. Sterculia foetida biodiesel–diesel blends of 5% show its capability to replace diesel fuel by providing engine peak performance than diesel fuel.

This article looks at the national and global actors, social networks, and narratives that have influenced Jatropha’s worldwide acceptability as a biofuel crop. Jatropha Curcas is a genus of around 175 succulent shrubs and trees in the Euphorbiaceae family (some of which are deciduous, such as Jatropha Curcas L.). It’s a drought-tolerant perennial that thrives in poor or marginal soil and produces a large amount of oil per hectare. It is easy to grow, has a fast growth rate, and can generate seeds for up to 50 years. Jatropha Curcas has been developed as a unique and promising tropical plant for augmenting renewable energy sources due to its various benefits. It is deserving of being recognised as the only competitor in terms of concrete and intangible environmental advantages. Jatropha Curcas is a low-cost biodiesel feedstock with good fuel properties and more oil than other species. It is a non-edible oilseed feedstock. Thus it will have no impact on food prices or the food vs fuel debate. Jatropha Curcas emits fewer pollutants than diesel and may be used in diesel engines with equivalent performance. Jatropha Curcas also makes a substantial contribution to the betterment of rural life. The plant may also provide up to 40% oil yield per seed based on weight. This study looks at the features characteristics of Jatropha Curcas as biodiesel feedstock and performance, and emissions of internal combustion engine that operates on this biodiesel fuel.

This study investigated the effect of the duty cycle for the transesterification of Ceiba pentandra oil. The important parameters of a duty cycle (pulse-mode operation) and energy usage in the transesterification reaction process were presented and showed that a maximum biodiesel yield of 99.24 % was achieved for 75% duty cycle with a pulse combination of 6 sec ON and 2 sec OFF. That was under the optimum conditions of 60% methanol to oil ratio, 1.00 wt% of KOH, reacted for 50 minutes. The obtained biodiesel was then analyzed using FTIR spectroscopy, and physiochemical properties of the Ceiba pentandra biodiesel then determined. It found that all the properties comply with the fuel specifications set by both ASTM D6751 and EN 14214 standards.

The limitation of fossil fuel sources and negative environmental impact persuade scientists around the world to find a solution. One possible solution is by using renewable fuel to replace fossil fuel with an inexpensive, fast, and effective production process. The objective of this study is to investigate the biodiesel production from crude Reutealis trisperma oil using the conventional and the ultrasonic bath stirrer method through the esterification and transesterification process. The result shows that the most effective reaction time with an optimum condition for the esterification and transesterification of Reutealis trisperma oil is at 2 h 30 min by using the ultrasonic bath stirrer method. The optimum conditions at a temperature of 55 °C for the esterification and at 60 °C for transesterification with 2% (v/v) of sulphuric acid with catalyst concentration of 0.5 wt.% were a methanol-to-oil ratio of 60%, and agitation speed of 1000 rpm. This optimum condition gives the highest yield of 95.29% for the Reutealis trisperma biodiesel. The results showed that the ultrasonic bath stirrer method had more effect on the reaction time needed than using the conventional method and reduced half of the conventional method reaction time. Finally, the properties of Reutealis trisperma biodiesel fulfilled the ASTM D6751 and EN 14214 biodiesel standards with density, 892 kg/m3; pour point, −2 °C; cloud point, −1 °C; flash point, 206.5 °C; calorific value, 40.098 MJ/kg; and acid value, 0.26 mg KOH/g

The ultrasound method is used to improve mass transfer between incompressible reactants which increases their chemical reaction and reduces reaction time as well as energy consumption. In this research, transesterification process variables of rice bran oil were optimized using response surface methodology (RSM). Three process parameters were investigated, namely methanol to oil molar ratio, catalyst concentration, and time. The optimum conditions of the transesterification process based on RSM were: (1) methanol to oil molar ratio: 1:6; (2) catalyst concentration: 0.5% wt.; and (3) time: 48 min, with methyl ester yield of 94.12 %. The optimum rice bran methyl ester yield predicted by RSM was validated by replicating three independent parameters with showed average rice bran methyl ester yield of 93.98%. The properties of the rice bran biodiesel properties were measured and the values met the requirements of the ASTM D6751 and EN 14214 standards.

The depletion of world oil reserves currently positively impacts the development of biofuels such as biodiesel and bioethanol, as this fuel is a renewable and environmentally friendly alternative and is considered to have enormous potential to supply energy needs. The purpose of this research is to investigate the performance and exhaust emissions from single diesel direct injection diesel engine which is fueled by biodiesel-bioethanol-diesel. Biodiesel was obtained from a mixture of Jatropa curcas-Ceiba pentandra crude oil with each composition being 50% produced by degumming process, acid catalyzed esterification, and alkaline-catalyzed transesterification. Biodiesel-bioethanoldiesel fuel is mixed in several conditions ie B10BE5, B20BE8, B30BE10, B40BE13, and B50BE15. In general, engine performance for low blend of biodiesel and bioethanol is close to diesel, for some engine parameters such as engine torque, brake power, and brake thermal efficiency. The addition of biodiesel and bioethanol into diesel fuel also has implications for reduced carbon emissions and smoke opacity. Overall, based on test results it can be concluded that the biodiesel-bioethanol mixture in low concentration in diesel fuel qualifies as an alternative fuel in diesel engines.

The depletion of fossil fuels, rising of earth temperatures and declining of air quality are an unavoidable phenomenon today. This condition is a result of increased and excessive use of fossil fuels. Bioethanol fuel is one solution to reduce this problem that is sourced from renewable raw materials. Sorghum seeds are raw materials that have the potential to be made bioethanol due to they have a high carbohydrate content (70%). The test is performed the use of pertalite-bioethanol blends fuels was on a four-stroke gasoline engine without modification. The percentage of the mixture volume of fuel used is 10% bioethanol-90% pertalite (E10), 15% bioethanol-85% pertalite (E15) and 20% bioethanol-80% pertalite (E20). Engine speeds vary from 1000 to 4000 rpm, and properties of the sorghum seeds bioethanol-pertalite blends are measured and analyzed. The purpose of this study is to investigate engine performance and exhaust emissions at gasoline engine by using the sorghum seeds bioethanol-pertalite blends with different mixed ratios (E10, E15 and E20). The Engine performance includes engine torque, brake specific fuel consumption (BSFC) and thermal brake efficiency (BTE) analyzed. In addition, carbon monoxide (CO), hydrocarbon (HC), and nitrogen oxide (NOx) emissions are measured as gasoline engine exhaust emissions. The results show that BSFC decreased while BTE increased for a fuel blends containing 20% bioethanol at 3500 rpm engine speed, with each maximum value of 246.93 g/kWh and 36.28%. It is also found that CO and HC emissions are lower for the sorghum seeds bioethanol-pertalite blends. Based on the research results, it can be concluded that the sorghum seeds bioethanol-pertalite blends can improve engine performance and reduce exhaust gas emissions.

Global warming in relation to fossil fuel pollution and their environmental impacts have become a major global concern. Biodiesel has entered the scene as an alternative fuel but it also generated controversy associated with increased residual fuel, increased acidity, oxidation, and corrosion. The main objective of this study was to observe the corrosion behavior of the mild steel immersed in J50C50 biodiesel-diesel fuel blends for up to 800 h at ambient temperature. The results showed corrosion rate at 800-h immersion are 0.0103, 0.0044, 0.0117, 0.0155, 0.2283 and 0.02524 mm/year, respectively, for B0, B10, B20, B30, B40 and B50. Mild steel coupon surface observation using SEM showed corrosion attacks are characterized by round holes on the metal surface. The addition of J50C50 biodiesel into diesel fuel accelerated the corrosion rate and acid value. Overall, corrosion observations conducted on mild steel suggested J50C50 biodiesel-diesel fuel blend is more corrosive compared with diesel fuel.

© 2019 by the authors. This study aimed to observe the potential of solid bioethanol as an alternative fuel with high caloric value. The solid bioethanol was produced from liquid bioethanol, which was obtained from the synthesis of oil palm empty fruit bunches (PEFBs) through the delignification process by using organosolv pretreatment and enzymatic hydrolysis. Enzymatic hydrolysis was conducted using enzyme (60 FPUg-1 of cellulose) at a variety of temperatures (35 °C, 70 °C, and 90 °C) and reaction times (2, 6, 12, 18, and 24 h) in order to obtain a high sugar yield. The highest sugars were yielded at the temperature of 90 °C for 48 h (152.51 mg/L). Furthermore, fermentation was conducted using Saccharomyces cerevisiae. The bioethanol yield after fermentation was 62.29 mg/L. Bioethanol was extracted by distillation process to obtain solid bioethanol. The solid bioethanol was produced by using stearic acid as the additive. In order to get high-quality solid bioethanol, the calorific value was optimized using the response surface methodology (RSM) model. This model provided the factor variables of bioethanol concentration (vol %), stearic acid (g), and bioethanol (mL) with a minus result error. The highest calorific value was obtained with 7 g stearic acid and 5 mL bioethanol (43.17 MJ/kg). Burning time was tested to observe the quality of the solid bioethanol. The highest calorific value resulted in the longest burning time. The solid bioethanol has a potential as solid fuel due to the significantly higher calorific value compared to the liquid bioethanol.

© 2019 The Author(s). Background: Microalgae are one of the promising feedstock that consists of high carbohydrate content which can be converted into bioethanol. Pre-treatment is one of the critical steps required to release fermentable sugars to be used in the microbial fermentation process. In this study, the reducing sugar concentration of Chlorella species was investigated by pre-treating the biomass with dilute sulfuric acid and acetic acid at different concentrations 1%, 3%, 5%, 7%, and 9% (v/v). Results: 3,5-Dinitrosalicylic acid (DNS) method, FTIR, and GC-FID were employed to evaluate the reducing sugar concentration, functional groups of alcohol bonds and concentration of bioethanol, respectively. The two-way ANOVA results (p < 0.05) indicated that there was a significant difference in the concentration and type of acids towards bioethanol production. The highest bioethanol yield obtained was 0.28 g ethanol/g microalgae which was found in microalgae sample pre-treated with 5% (v/v) sulfuric acid while 0.23 g ethanol/g microalgal biomass was presented in microalgae sample pre-treated with 5% (v/v) acetic acid. Conclusion: The application of acid pre-treatment on microalgae for bioethanol production will contribute to higher effectiveness and lower energy consumption compared to other pre-treatment methods. The findings from this study are essential for the commercial production of bioethanol from microalgae.

© 2019 by the authors. Optimizing the process parameters of biodiesel production is the key to maximizing biodiesel yields. In this study, artificial neural network models integrated with ant colony optimization were developed to optimize the parameters of the two-step Cerbera manghas biodiesel production process: (1) esterification and (2) transesterification. The parameters of esterification and transesterification processes were optimized to minimize the acid value and maximize the C. manghas biodiesel yield, respectively. There was excellent agreement between the average experimental values and those predicted by the artificial neural network models, indicating their reliability. These models will be useful to predict the optimum process parameters, reducing the trial and error of conventional experimentation. The kinetic study was conducted to understand the mechanism of the transesterification process and, lastly, the model could measure the physicochemical properties of the C. manghas biodiesel.

The appealing second generation bioethanol production brings a good promise to achieve a fuel production that is renewable and sustainable; this makes durian (Durio zibethinus) seed interesting to take advantage of, especially for a tropical country like Malaysia. This paper aims to produce bioethanol from durian seed by utilizing ultrasound technique in its enzymatic hydrolysis process. 9 % (w/v) pre-Treated durian seed was brought into the ultrasound-Assisted glass reactor to begin the liquefaction and saccharification processes. Bacillus licheniformis Type XII-A was employed, and ultrasound at 50% amplitude for 60 min was set for liquefaction process; while amyloglucosidase from Aspergillus niger was used, and ultrasound at 40% amplitude for 120 min was run for saccharification process. The sum of both processes in hydrolysis yielded 41.07 g/L of reducing sugar, which was immediately brought to fermentation stage. Saccharomyces cerevisiae was employed for fermentation and resulted 18.48 g/L (0.44 g ethanol/g glucose), which is equivalent to 86.27 % of theoretical ethanol yield (0.51 g ethanol/g glucose) after 84 h of fermentation at 37 °C with 150 rpm incubator shaker. The ethanol purity was improved in the next stage, distillation. Using zeolite as adsorbent, ethanol with purity of 95.7% (v/v) was produced. From the acquired results, durian seed shows a justifiably potential as a second generation bioethanol feedstock. To further improve its potential, studies of optimization using this feedstock is highly encouraged.

Tulisan ini meneliti kinerja mesin diesel satu silinder menggunakan campuran bahan bakar biodiesel randu dengan solar. Tes dilakukan dengan berbagai perbandingan biodiesel-diesel (B10, B20 dan B30). Sebuah model artificial neural network (ANN) yang didasarkan pada algoritma back-propagasi standar digunakan untuk memprediksi kinerja mesin menggunakan MATLAB. Untuk memperoleh data untuk pelatihan dan pengujian yang diusulkan ANN, kecepatan mesin yang berbeda (1400-2200 rpm) dipilih sebagai parameter masukan, sedangkan kinerja mesin (BSFC dan BTE) dipilih sebagai parameter keluaran untuk ANN pemodelan dari mesin diesel. Kinerja mesin (BSFC dan BTE) ANN telah divalidasi dengan membandingkan hasil prediksi dengan hasil eksperimen. Hasil penelitian menunjukkan bahwa koefisien korelasi BSFC dan BTE masing masing adalah 0,99249 dan 0,99457. Nilai MAPE (mean absolute persentase kesalahan) BSFC dan BTE adalah 0,57467 dan 0,33424 dan root mean square (RSME) nilai di bawah 5% oleh model, yang diterima. Studi ini menunjukkan bahwa pemodelan teknik sebagai pendekatan dalam energi alternatif dapat memberikan peningkatan keuntungan dari kehandalan dalam prediksi kinerja mesin pembakaran dalam.

It is a popular fact that the world's dependency on fossil fuel has caused unfavourable effects, including lessening crude oil reserve, decreasing air quality, rising global temperature, unpredictable weather change, and so on. As the effort to promote sustainability and independency from fossil fuel, bioethanol is now favoured as the blend or fossil petrol substitute. However, the feedstock functionality of first generation bioethanol production is restricted due to its edibleness since it would clash the feeding purpose. Second generation bioethanol production fulfils the impractical gap of first generation since it employs non-edible feedstock sourced from agriculture and forestry wastes. Lignocellulosic and starchy materials in them are convertible to fermentable sugars that are able to be further processed, resulting anhydrous bioethanol as the end product. This paper critically reviews the existing variance of second generation bioethanol production methodologies, namely pre-treatment, hydrolysis, fermentation and distillation, as well as the worth of second generation production for future reference. The discussions in this paper are also fit as the fundamental for feasible planning of second generation bioethanol production plant.

Rising global temperature, worsening air quality and drastic declining of fossil fuel reserve are the inevitable phenomena from the disorganized energy management. Bioethanol is believed to clear out the effects as being an energy-derivable product sourced from renewable organic sources. Second generation bioethanol interests many researches from its unique source of inedible biomass, and this paper presents the potential of several selected biomasses from Malaysia case. As one of countries with rich biodiversity, Malaysia holds enormous potential in second generation bioethanol production from its various agricultural and forestry biomasses, which are the source of lignocellulosic and starch compounds. This paper reviews potentials of biomasses and potential ethanol yield from oil palm, paddy (rice), pineapple, banana and durian, as the common agricultural waste in the country but uncommon to be served as bioethanol feedstock, by calculating the theoretical conversion of cellulose, hemicellulose and starch components of the biomasses into bioethanol. Moreover, the potential of the biomasses as feedstock are discussed based on several reported works.

Biodiesel is an alternative renewable resource to petroleum-based diesel. The aim of using biodiesel is to reduce environmental pollution and combat global warming. Biodiesel application in compression ignition engines has shown its compatibility with better combustion characteristics and high engine performance. Many advantages can be obtained by using biodiesel, including reducing exhaust gases, reducing air toxicity, providing energy security, and being biodegradable. However, biodiesel’s disadvantage involves oxidation stability, corrosion, degradation, and compatibility with other metallic materials. The present study investigates the corrosive behavior of the ternary blend (waste cooking-Calophyllum inophyllum biodiesel-diesel) fuel that occurs in contact with mild steel and stainless steel 316. The observation study for mild steel and stainless steel 316 material under the static immersion method was performed for 7,200 h and 14,400 h, respectively, at room temperature (25°C–30°C). In every 720 and 1,440 h of immersion time, the coupon’s profile was analyzed by scanning electron microscopy (SEM)/electron-dispersive spectrometer (EDS), and the mass loss was observed, for corrosivity investigation. Based on the obtained results, the average corrosion rate of mild steel and stainless steel 316 is 0.6257 and 0.0472 nm/year at 7,200 h, respectively; the difference in corrosion rate for these metallic materials is approximately 92.46%. The degradation of the fuel properties such as kinematic viscosity, density, refractive index, and acid value was monitored. In this study, stainless steel 316 was more resistant to corrosion attack with some micro pitting and showed better compatibility with the ternary blend than mild steel. The regression analysis and the correlation of corrosion rate were studied.

Biodiesel is an alternative renewable resource to petroleum-based diesel. The aim of using biodiesel is to reduce environmental pollution and combat global warming. Biodiesel application in compression ignition engines has shown its compatibility with better combustion characteristics and high engine performance. Many advantages can be obtained by using biodiesel, including reducing exhaust gases, reducing air toxicity, providing energy security, and being biodegradable. However, biodiesel’s disadvantage involves oxidation stability, corrosion, degradation, and compatibility with other metallic materials. The present study investigates the corrosive behavior of the ternary blend (waste cooking-Calophyllum inophyllum biodiesel-diesel) fuel that occurs in contact with mild steel and stainless steel 316. The observation study for mild steel and stainless steel 316 material under the static immersion method was performed for 7,200 h and 14,400 h, respectively, at room temperature (25°C–30°C). In every 720 and 1,440 h of immersion time, the coupon’s profile was analyzed by scanning electron microscopy (SEM)/electron-dispersive spectrometer (EDS), and the mass loss was observed, for corrosivity investigation. Based on the obtained results, the average corrosion rate of mild steel and stainless steel 316 is 0.6257 and 0.0472 nm/year at 7,200 h, respectively; the difference in corrosion rate for these metallic materials is approximately 92.46%. The degradation of the fuel properties such as kinematic viscosity, density, refractive index, and acid value was monitored. In this study, stainless steel 316 was more resistant to corrosion attack with some micro pitting and showed better compatibility with the ternary blend than mild steel. The regression analysis and the correlation of corrosion rate were studied.