Maximum Biodiesel Yield Research Articles

Enhancement of biodiesel yield and characteristics through in-situ solvo-thermal co-transesterification of wet microalgae with spent coffee grounds

This study evaluated in-situ co-transesterification of wet spent coffee ground (SCG)/microalgae mixture for enhanced biodiesel production. SCG and microalgae showed lipid contents of 16.0 and 23.6 wt%, respectively. A total of 27 transesterification runs were performed using wet SCG:algae (1:1, w/w) at different temperatures, times, and solvent ratios. Box-Behnken quadratic model suggested 198 °C, 6 mL solvent g−1 biomass, and reaction time of 132 min as the optimum conditions for maximum biodiesel yield. At different SCG/microalgae blend ratios, pure microalgae showed the highest biodiesel yield of 20.15 wt%. Increase of SCG ratio resulted in significant reduction in the biodiesel yield, reaching the lowest value of 11.2 wt% using pure SCG. On the other hand, SCG showed better biodiesel characteristics than microalgae regarding iodine value, cetane number, and oxidation stability. The present results confirmed that SCG-algae blend results in dual effect of enhancing biodiesel yield and quality, comparing to the individual transesterification.

Simultaneous esterification and transesterification of waste phoenix seed oil with a high free fatty acid content using a free lipase catalyst to prepare biodiesel

Biodiesel is a typical renewable and green energy, that is usually produced by the transesterification of edible vegetable oils. However, the cost of edible vegetable oils as feedstock accounts for 60%–80% of the total cost of biodiesel production. To overcome these issues, in this work, a low-cost feedstock, waste phoenix seed oil (PSO) with a high free fatty acid (FFA) content (30.1 ± 0.6%), consisting of the main fatty acid, linoleic acid (30.2%), oleic acid (22.2%), and palmitic acid (17.4%), was developed as a new feedstock to prepare biodiesel. A novel one-step method including simultaneous esterification of FFAs and transesterification of the PSO to prepare biodiesel was developed. Free lipase was used as catalyst. The influences of the reaction parameters were explored and optimized by response surface methodology. The results showed that the free lipase Lipozyme TL100L from Thermomyces lanuginosus can simultaneously catalyze esterification and transesterification. Under the optimum conditions (enzyme load 9.7%, reaction time 6.9 h, reaction temperature 31 °C and substrate ratio (methanol/PSO) 4.3: 1 (mol/mol)), the maximum biodiesel yield (93.8 ± 0.5%) was achieved. The activation energy from biodiesel preparation using PSO with a high FFA content was 39.7 kJ/mol. Furthermore, the kinetic values for K'm and Vmax were 0.18 mol/L and 0.043 mol/(L·min), respectively. The reaction mechanism of the simultaneous esterification and transesterification was also proposed. These results indicate that PSO with a high FFA content can be used as a potential feedstock for biodiesel production.

Synthesis and characterization of bifunctional magnetic nano-catalyst from rice husk for production of biodiesel

In this work, bifunctional magnetic nano-catalyst was successfully derived from rice husk char doped with potassium oxide and nickel oxide by impregnation techniques, and their catalytic ability was tested via transesterification of used cooking oil (UCO). The catalyst was characterized by thermogravimetric analyzer (TGA), X-ray diffraction spectroscopy (XRD), Fourier-transform infrared spectroscopy (FTIR), Temperature programmed desorption (TPD), Brunauer–Emmett–Teller (BET), Scanning electron microscopy equipped with energy dispersive x-ray analyzer (FESEM-EDX), and Vibrating sampling magnetometer (VSM) for magnetic properties. The optimized nanomagnetic bifunctional catalyst (RHC/K 2 O-20%/Ni-5%) had 3.014 mmol g − 1 & 4.485 mmol g − 1 of acidity and basicity, respectively, with the magnetic strength was recorded at 2.312 emu g −1 . For the catalytic evaluation, a maximum biodiesel yield of 98.2% was accomplished with 4 wt% of catalyst loading, 12:1 methanol to UCO molar ratio at 65 °C within 2 h of reaction time. The catalyst was reused for up to 5 reaction cycles and producing 70% of biodiesel at the last cycles. The fuel properties of optimized biodiesel were measured using Biodiesel - American Standard Testing Method (ASTM) D6751. Due to the magnetic properties of the catalyst, it was easily recovered by an external magnetic device and has the potential to improve the separation and purification processes. • The magnetic RHC/K 2 O-20%/Ni nano-catalysts was prepared for better separation process. • Catalysts magnetic strength were determined by using VSM (2.312 emu g -1 ). • The effect of operating parameters on biodiesel synthesis were studied. • The magnetic RHC/K 2 O-20%/Ni nano-catalysts could produce 98% biodiesel with 5 reaction cycles.

Optimisation and prediction of Karanja oil transesterification with domestic microwave by RSM and ANN

Optimisation and estimation of biodiesel by Karanja oil (KO) was done by response surface methodology (RSM) and artificial neural networks (ANNs) models through domestic microwave heating transesterification. Box–Behnken experimental design was adopted. Four process parameters are methanol/oil mole ratio (30–50%), catalyst concentration (1–2 wt%), volume (100–300 mL) and time (4–8 min). Biodiesel with a yield of 87.34% was obtained using 1.5 wt. % NaOH, 35% methanol to oil molar ratio, 150 mL amount and 5 min of reaction at 700 W power with 100 rpm stirring. The physico-chemical characteristics of KO methyl ester are measured using standard methods. Quality of RSM model is analysed by analysis of variance. ANN tool was adopted for modelling and prediction. Correlation coefficient values were 0.85 and 0.8663 with RSM and ANN, respectively. The concentration of the catalyst, volume, methanol to oil molar ratio and time required producing maximum yield of biodiesel were obtained. The predictive capacities of RSM and ANN are evaluated and compared by statistical parameters, namely,R 2, RMSE, ADJ-R 2 and MSE. Hence, results typify the strength and excellence of ANN over RSM specifically in the transesterification of biodiesel.

Effect of K-Silica heterogeneous catalyst in transesterification reaction of crude palm oil

Crude Palm Oil (CPO) is a raw material form of vegetable oil that cannot be consumed anymore and where the availability is very large. The purpose of this study was to observe the use of crude palm oil in the manufacturing of biodiesel by using a catalyst of bamboo ash leaves catalyst impregnated with KOH to get in the best yield of various reaction variables performed. The transesterification process reacted oil and methanol to produce methyl esters and glycerol. The methyl ester was produced at the top layer and it was separated from the glycerol and then washed. The effects of various process variables such as the type of the catalyst, the amount of catalyst, and time of reaction were observed in this experiment. The properties of biodiesel such as ester content, density, and kinematic viscosity, were evaluated and compared with Standard Nasional Indonesia (SNI). Under the best conditions, the maximum yield of biodiesel was 92.58% and 99.76% FAME methyl ester was 99.76% obtained using a molar ratio of oil: methanol of 1: 9 at 65°C with a reaction time of 2 hours and 4% catalyst. The results obtained in this study indicated that the K-Silica catalyst of KOH impregnated ash bamboo leaves is suitable as a catalyst to produce biodiesel.

A solar reactor for bio-diesel production from Pongamia oil: Studies on transesterfication process parameters and energy efficiency

Abstract Over exploitation of non-renewable energy reserves will lead to increase in price of petroleum fuels. Therefore there is a need for suitable and sustainable substitutes (renewable resource) for conventional fuels. In this study, an efficient and environmental friendly method for production of bio-diesel from Pongamia (Karanja) oil has been developed using a solar reactor. During the experimental study, the maximum temperature attained by the pongamia oil during the transesterification process was 64.1°C. The transesterification reaction was studied by varying different parameters such as reactant flow rate (5-20 LPH), stirring speed (150-450 r·min-1), catalyst loading (0.5 wt% -2 wt%) and methanol to oil ratio (3:1 to 15:1). The maximum biodiesel yield was 83.11% at a flow rate of 5 LPH, stirring speed of 350 rpm, a methanol to oil ratio of 15:1, catalyst loading of 1wt % and reaction time of 270 min. The physical and chemical properties of biodiesel was analyzed as per American Society for Testing Materials (ASTM) standards and it had density of 938 kg·m-3, viscosity (28.7 cSt), acid value (9.45 mg KOH·(g oil)-1) and flash point (215°C). The energy efficiency of solar heating process was determined by comparing the net energy ratio of direct heating process and solar heating process. For solar heating the net energy ratio (NER) was found to be 31.85 against 5.73 for direct heating. Similarly, net energy efficiency index was calculated for 10 kg production scale and was found to be increasing when scaled up which means that the solar heating process is more effective even in scaled up production.

Biodiesel production from novel non-edible caper (Capparis spinosa L.) seeds oil employing Cu–Ni doped ZrO2 catalyst

The rapid depletion of fossil fuel resources and climatic changes has triggered the researchers' attention to find an alternative and renewable energy source. Thus, biodiesel has been recognized as a potential alternative to petrodiesel for its biodegradability, non-toxicity, and environment-friendly attributes. In this study, an efficient and recyclable Cu–Ni doped ZrO2 catalyst was synthesized and used to produce biodiesel from a novel non-edible caper (Capparis spinosa L.) seed oil. The synthesized catalyst was characterized by x-ray diffraction, fourier-transform infrared spectroscopy, scanning electron microscopy, and energy dispersive x-ray analysis. The catalyst was reused in four consecutive transesterification reactions without losing any significant catalytic efficiency. Transesterification reaction conditions were optimized via response surface methodology based on Box-Behnken design for predicting optimum biodiesel yields by drawing 3D surface plots. Maximum biodiesel yield of 90.2% was obtained under optimal operating conditions of 1:6 M ratio of oil to methanol, reaction temperature of 70 °C, reaction time of 1.5 h, and 2.5% catalyst loading. Fourier-transform infrared spectroscopy, gas chromatography–mass spectrometry, and nuclear magnetic resonance (1H and 13C) analysis confirmed the high quality of biodiesel produced from non-edible caper (Capparis spinosa L.) seed oil. The fuel properties of the produced biodiesel were also found, such as kinematic viscosity (4.17 cS T), density (0.8312 kg/L), flash point (72 °C), acid no (0.21 mgKOH/g) and sulphur content (0.00042 wt%). These properties were matched and are in close agreement with the International Biodiesel Standards of European Union (EU-14214), China GB/T 20,828 (2007), and American (ASTM6751). Thus, non-edible Capparis spinosa L. seed oil and Cu–Ni doped ZrO2 catalyst appeared to be highly active, stable, and cheap candidates to boost the future biodiesel industry.

Nile tilapia industrialization waste: Evaluation of the yield, quality and cost of the biodiesel production process

The biodiesel produced from Nile tilapia waste consists of an alternative material for sustainable energy production, meeting the growing energy demand without damaging the environment, being this fish waste is often disposed in the inadequate form. The aim of this work was to investigate the biodiesel production from fish oil extracted from Nile tilapia processing waste (heads), through a full factorial experimental design. The biodiesel production was carried out by homogeneous alkaline transesterification using ethanol, and potassium hydroxide (KOH) as the catalyst. The best condition of biodiesel production was evaluated as a function of the catalyst concentration, oil:ethanol molar ratio and reaction time, according to the factorial design and the responses were yield, production cost, acid value, and kinematic viscosity. The maximum yield of biodiesel was 92% (w w−1), this result was obtained with KOH 2% (w w−1), molar ratio of 1:12 (oil: ethanol) and reaction time of 4 h. This condition also ensured a product with lower VA (0.63 mgKOH g−1), lower kinematic viscosity (2.78 mm2 s−1), and a low cost of biodiesel production (0.17 US$ kg−1). TLC and FTIR analyses pointed out that the triglycerides of the fish oil were converted into biodiesel. The fatty acids profiles for the crude oil, bleached oil and biodiesel from Nile tilapia oil were determined by gas chromatography and, they have not presented significant differences in their percentage values. Based on the lipid profile obtained, Nile tilapia oil showed suitable characteristics, being a promising source for biodiesel obtainment. This study showed that bleached oil from Nile tilapia heads stands out as a promising source for producing biodiesel with high yield, positive economic potential, and better physicochemical properties.

Biodiesel production from low-grade oil using heterogeneous catalyst: an optimisation and ANN modelling

ABSTRACT In this work, waste chicken eggshell (WCES) was used as a heterogeneous catalyst for the production of biodiesel from waste cooking oil (WCO). The catalyst was prepared via calcination technique. Response Surface Method (RSM) optimisation and Artificial Neural Network (ANN) modelling were performed to achieve maximum biodiesel yield. Both models perform reasonably well in achieving maximum biodiesel yield (91%). However, the efficacy of the models was determined with R2, R (coefficient of determination), and MSE (mean square error). Results show that the ANN model achieved the highest R2 (98.48), R (99.24), and lowest MSE (0.08) compared to the RSM model. This shows that ANN predictive capability was more accurate. The fatty acid composition (FAC) analysis by GCMS reveals that 56.75% unsaturated and 41.99% saturated were recognised. The key physicochemical properties of biodiesel satisfy the standards of ASTMD6751 and EN 14,214.

Production of high quality biodiesel from novel non-edible Raphnus raphanistrum L. seed oil using copper modified montmorillonite clay catalyst

This study focused on producing high quality and yield of biodiesel from novel non-edible seed oil of abundantly available wild Raphnus raphanistrum L. using an efficient, recyclable and eco-friendly copper modified montmorillonite (MMT) clay catalyst. The maximum biodiesel yield of 83% was obtained by base catalyzed transesterification process under optimum operating conditions of methanol to oil ratio of 15:1, reaction temperature of 150 °C, reaction time of 5 h and catalyst loading of 3.5%. The synthesized catalyst and biodiesel were characterized for their structural features and chemical compositions using various state-of-the-art techniques, including x-ray diffraction, scanning electron microscopy, energy dispersive x-ray spectroscopy, Fourier transform infrared spectroscopy, nuclear magnetic resonance (1H, 13C) and gas chromatography-mass spectroscopy. The fuel properties of the biodiesel were estimated including kinematic viscosity (4.36 cSt), density (0.8312 kg/L), flash point (72 °C), acid value (0.172 mgKOH/g) and sulphur content (0.0002 wt.%). These properties were compared and found in good agreement with the International Biodiesel Standards of American (ASTM-951, 6751), European Committee (EN-14214) and China GB/T 20828 (2007). The catalyst was re-used in five consecutive transesterification reactions without losing much catalytic efficiency. Overall, non-edible Raphnus raphanistrum L.. seed oil and Cu doped MMT clay catalyst appeared to be highly active, stable, and cheap contenders for future biofuel industry. However, detailed life cycle assessment (LCA) studies of Raphnus raphanistrum L. seed oil biodiesel are highly recommended to assess the technical, ecological, social and economic challenges.

Coconut fatty acid distillate as novel feedstock for biodiesel production and its characterization as a fuel for diesel engine

The coconut fatty acid distillate (CFAD) was used as a novel feedstock for biodiesel production in this investigation. Its characterization as fuel in diesel engine was also studied. A maximum biodiesel yield of 92.6% was obtained, when esterification is performed with 10:1 methanol to oil ratio, 2.5% sulphuric acid at 60 °C for 90 min. This is followed by transesterification with optimized parameters of methanol to oil ratio 8:1, 1.5% potassium hydroxide at 60 °C for 90 min. 20%, 40%, 60% and 100% of CFAD biodiesel (CFAB) was added to diesel to form blends CFAB20, CFAB40, CFAB60 and CFAB100. Engine test results showed that the performance of CFAB20 is closer to diesel than the other CFAB blends. The brake thermal efficiency (BTE) of CFAB20 was found to be 4.7% lesser than diesel. Nitrogen oxide emission is higher for all biodiesel blends due to enhanced combustion characteristics. However, carbon monoxide, hydrocarbon and smoke were reduced by 50%, 36.6% and 42.9% respectively for CFAB100 when compared to diesel at full load. Thus it is inferred that the CFAD is a potential source for biodiesel production. CFAB20 can be used in diesel engines with acceptable BTE and reduced emissions without any engine modification.

A novel Citrus sinensis peel ash coated magnetic nanoparticles as an easily recoverable solid catalyst for biodiesel production

A magnetic nano-sized solid catalyst derived from bio-waste Citrus sinensis peel ash (CSPA)@Fe3O4 was developed for the synthesis of biodiesel from waste cooking oil (WCO). The core–shell structure of the catalyst enhanced the surface properties and maintained a controlled size and shape of the catalyst, thus improved the catalyst stability to a great extent. The synthesized catalyst was characterized by several analysis techniques. The high amount of potassium and calcium in the Citrus sinensis peel ash (CSPA) catalyst makes it extremely basic and played an important catalytic role in the transesterification of WCO. The CSPA@Fe3O4 catalyzed transesterification afforded a maximum biodiesel yield of 98% under the optimized reaction conditions such as 6:1 methanol/oil molar ratio, 6 wt% catalyst loading, 65 °C temperature and 3 h time. The activation energy of the reaction was found to be 34. 41 KJ mol−1, which indicated that the transesterification of WCO using the present catalyst is chemically controlled reaction. Beneficially, the magnetic iron oxide core endorsed easily recoverable of the catalyst from the reaction mixtures by using an external magnet. Moreover, the catalyst showed high physical stability and reactivity up to the 9 consecutive cycles, demonstrating it as a promising solid base catalyst for sustainable production of biodiesel.

Efficient reaction for biodiesel manufacturing using bi-functional oxide catalyst

The search for biofuel in order to complement the future shortage of fuels and mitigate the poisonous air and water pollution has become so considerate in the last few decades. The choice of feedstock and catalyst system for biofuel production has been very difficult considering many drawbacks from food-fuel competition to catalyst separation and water washing after the reaction. To address these issues, acid-base bi-functional catalysts and waste based vegetable oil were considered for the sustainable production of biofuels. Bifunctional catalyst has the capacity to successfully transform waste based vegetable oil into useful biofuel under mild reaction parameters. In this work, a newly developed bimetallic tungsten- zirconia (WZr) modified waste shell catalyst samples were employed for the simultaneous esterification and transesterification of unrefined palm-derived waste oil (PDWO) to biodiesel in one-pot reaction. These catalysts were successfully synthesized using simple wet impregnation technique and characterized by SEM, BET, XRD, and TPD characterization techniques. The catalyst was able to achieved the maximum biodiesel yield of 94.1% in 1 h under optimized reaction parameters.

Application of response surface methodology for optimization of biodiesel production parameters from waste cooking oil using a membrane reactor

In light of the growing concerns over depleting energy resources, alternative renewable fuels such as biodiesel have been identified as a possible means of addressing this crisis. In biodiesel production, waste cooking oil (WCO) is seen as the ideal alternative feedstock to vegetable oils, which are part of the food chain. The need to obtain high quality biodiesel at minimal cost has driven the idea to use membrane reactors, which offers the ability to achieve both reaction and separation processes simultaneously. Design and optimization studies were conducted using sulphated zirconia pre-treated WCO as feed stock. Response surface methodology modelling was used to investigate the effect of reaction temperature, catalyst concentration and circulation flow rate in biodiesel production using membrane reactors. This is because limited data is available, particularly considering circulation flow rate effect on biodiesel production using membrane reactors. Experimental results also show that the higher the catalyst to WCO ratio the higher the free fatty acids (FFA) content. A maximum biodiesel yield of 92. 6 mole % was obtained at a temperature of 61°C, circulation flow rate of 26 mL/min using KOH catalyst concentration of 1.3 wt % over a TiO2/Al2O3 membrane. Upon membrane optimization, a biodiesel yield of 94.03 mol % was obtained at 58.5 °C, circulation flow rate of 18.78 ml/min and catalyst concentration of 1.24 wt %. This analysis clearly shows that RSM can be successfully used to model reacting membranes using temperature, catalyst concentration and circulation flow rate to achieve higher yields for biodiesel production.

Magnetic biochar derived from waste palm kernel shell for biodiesel production via sulfonation

Due to its environment-friendly and replenishable characteristics, biodiesel has the potential to substitute fossil fuels as an alternative source of energy. Although biodiesel has many benefits to offer, manufacturing biodiesel on an industrial scale is uneconomical as a high cost of feedstock is required. A novel sulfonated and magnetic catalyst synthesised from a palm kernel shell (PMB-SO3H) was first introduced in this study for methyl ester or biodiesel production to reduce capital costs. The wasted palm kernel shell (PKS) biochar impregnated with ferrite Fe3O4 was synthesised with concentrated sulphuric acid through the sulfonation process. The SEM, EDX, FTIR, VSM and TGA characterization of the catalysts were presented. Then, the optimisation of biodiesel synthesis was catalysed by PMB-SO3H via the Response Surface Methodology (RSM). It was found that the maximum biodiesel yield of 90.2% was achieved under these optimum operating conditions: 65 °C, 102 min, methanol to oil ratio of 13:1 and the catalyst loading of 3.66 wt%. Overall, PMB-SO3H demonstrated acceptable catalysing capability on its first cycle, which subsequently showed a reduction of the reusability performance after 4 cycles. An important practical implication is that PMB-SO3H can be established as a promising heterogeneous catalyst by incorporating an iron layer which can substantially improve the catalyst separation performance in biodiesel production.

Transesterification of Crude Palm Oil (CPO) to Biodiesel Using Heterogeneous Catalyst K-CaO from Anadara Granosa Synthesized by Sol Gel Method

This study aimed to synthesize biodiesel from CPO using heterogeneous K-CaO catalyst from blood cockle (anadara granosa) shells. The catalyst was synthesized by sol gel method with variation calcination temperatures of 700, 800 and 900°C. The catalyst was characterized using X Rays Diffraction (XRD) and X-Ray fluorescence (XRF). The XRD results showed the presence of mineral lime, portlandite and calcite. Based on the XRF results that K-CaO heterogeneous catalyst contained 96,538% of calcium oxide (CaO). Biodiesel was synthesized by transesterification reaction with variations in time conditions (1, 2, 3 and 4 hours) and reaction temperature (50, 55, 60 and 65°C). The maximum biodiesel yield of transesterification reaction using heterogeneous K-CaO catalyst from blood cockle shell (anadara granosa) was 92,648% using catalyst calcination at a temperature of 700 °C and the optimum reaction time was 2 hours using 3% (w/w) catalyst, mol ratio of oil: methanol 1:6, stirring speed of 500 rpm and reaction temperature of 60 °C.

OPTIMIZATION OF BIODIESEL PRODUCTION FROM WASTE COOKING SUNFLOWER OIL BY TAGUCHI AND ANN TECHNIQUES

Sunflower oil is commonly used for cooking purposes. After their repetitive usage, these oils are treated as waste and being dumped. Due to the huge population, the utilization of oil for daily requirements is also high. Every day tonnes of waste cooking oil (WCO) are being discarded which eventually increases environmental pollution. Therefore, WCO was proposed to use for biodiesel production. To achieve maximum biodiesel yield with limited experiments, optimization techniques are popular. In this endeavor, nine experiments were conducted based on Taguchi orthogonal array and Artificial Neural Network (ANN) based feedforward backpropagation was used for validation of the transesterification process. A maximum yield of 92.17% was achieved at a molar ratio (MR) of 12:1, catalyst concentration (CC) of 15, reaction temperature at 550C and reaction time for one hour. CC was observed as the highest influence factor on biodiesel yield. The accuracy of the chosen optimization models was determined by the coefficient of determination which is almost the same for Taguchi (0.9959) and ANN (0.9955). This shows that these models are highly accurate in prediction. As a conclusion, by utilizing WCO for biodiesel production can decrease the overall production cost and the obtained biodiesel properties meet the international standards.

Tosylated cloisite as a new heterofunctional carrier for covalent immobilization of lipase and its utilization for production of biodiesel from waste frying oil

In this paper, cloisite 30B (CL) was converted to tosylated cloisite (TCL) as new heterofunctional support. Lipase from Candida rugosa was covalently immobilized on the TCL (TCLL) and used to produce biodiesel from waste frying oil (WFO). The effects of reaction time and temperature, the molar ratio of methanol/oil, and the water content on the biodiesel yield were also explored. The hydrolytic activity of TCLL was 1.96 ± 0.04 U mg−1, with the immobilization yield of 93.6% and expressed activity of 90.2%. The maximum yield of biodiesel (97.1 ± 1.1%) was obtained at 50 °C for 8 h with a 15:1 M ratio of methanol to WFO and water content 10 wt%. The features of produced biodiesel, such as acid value, iodine value, density, and viscosity, met the specifications in the reported standard test methods. After 24 h incubation at 80 °C, the relative yield of biodiesel for TCLL was 20.3%, while the relative yield for the free enzyme was almost zero. The relative yield of biodiesel for TCLL and free lipase was 70.6% and 33.4%, respectively, after 30 days of storage. Also, TCLL showed a relative yield of 61.3% in the biodiesel production after being used for 10 cycles.

Process optimization, reaction kinetics, and thermodynamics studies of water addition on supercritical methyl acetate for continuous biodiesel production

Biodiesel production from rapeseed oil using supercritical methyl acetate with water addition has been developed to attain a higher biodiesel yield than that of supercritical methyl acetate without water. We newly constructed a plug flow reactor for the supercritical reaction usage system. We examined the effect of process variables by utilizing response surface methodology to optimize the process. As a result, the maximum biodiesel yield of 97 wt% was achieved at water addition of 8.2 wt%, reaction temperature of 578 K, and space time of 30 min. From the pseudo-first order reaction model, it was found that water addition under supercritical methyl acetate escalates reaction rate and reduces the activation energy of the reaction. The water addition improved the thermodynamics activation parameters, including enthalpy, entropy, Gibb’s energy, and equilibrium constant based on the transition-state theory. The thermodynamics activation parameters obtained show that the reaction was endothermic and unspontaneous.

Analysis and optimisation of transesterification parameters for high-yield Garcinia Gummi-Gutta biodiesel using RSM and TLBO

ABSTRACT The consumption of fossil fuels is continuously increasing due to large number of automobiles and high demand for energy. Fossil fuels will not only become extinct in near future, but also pollute the environment. The present research work is focused on finding an eco-friendly alternate energy source through the production of bio-diesel. Naturally available low-cost Garcinia Gummi-Gutta seed was used to produce the biodiesel employing the transesterification process widely utilised in industries. The maximum biodiesel yield was primarily dependent on the optimisation of transesterification parameters (reaction time, percent of methanol and sodium hydroxide). Response Surface Methodologies (RSM) such as Box-Behnken design (BBD) and Central composite design (CCD) were used to conduct the experiments and analyse the transesterification parameters relationship with biodiesel yield. Results showed that, the methanol contribution was more as compared to sodium hydroxide and reaction time towards the yield of the biodiesel. The mathematical regression equations developed, related to biodiesel yield and transesterification parameters by utilising both the CCD and BBD models. The performance of BBD was found to be slightly better than that of CCD in making prediction of the biodiesel yield. Experimentally, the Teaching Learning-based Optimisation (TLBO) determined optimal transesterification parameters resulting to 96.2% biodiesel yield.