The utilization of waste egg and cockle shell as catalysts for biodiesel production from food processing waste oil using stirring and ultrasonic agitation

The use of calcined egg and cockle shell as heterogeneous solid catalysts for a transesterification reaction to produce biodiesel from food processing waste has been investigated in this work. The CaO catalysts were obtained from the calcination of egg and cockle shell and were characterized by surface analysis, X-ray diffractometry (XRD), and scanning electron microscopy (SEM). The experiments employed stirring and ultrasonic agitation, which proved to be a time-efficient approach for biodiesel production from food processing waste oil. A response surface methodology (RSM) was used to evaluate the effects of the process variables methanol to oil molar ratio, catalyst concentration, and reaction time on biodiesel production. The optimal % fatty acid methyl ester values obtained when using egg and cockle shells as catalysts were found to be 94.7% and 94.4% when the methanol to oil molar ratios were 9.3:1 and 8.5:1, egg and cockle shell catalyst mass fraction percentages were 3.8% and 3.5%, and reaction times were 47 and 44 min, respectively. The study has shown that ultrasonic agitation might be employed in a practical pilot reactor for biodiesel production.     

Biodiesel production from waste cooking oil using heterogeneous catalysts and its operational characteristics on variable compression ratio CI engine

In the present work, the optimum biodiesel conversion from waste cooking oil to biodiesel through transesterification method was investigated. The base catalyzed transesterification under different reactant proportions such as the molar ratio of alcohol to oil and mass ratio of catalyst to oil was studied for optimum production of biodiesel. The optimum condition for base catalyzed transesterification of waste cooking oil was determined to be 12:1 and 5 wt% of zinc doped calcium oxide. The fuel properties of the produced biodiesel such as the calorific value, flash point and density were examined and compared to conventional diesel. The properties of produced biodiesel and their blend for different ratios (B20, B40, B60, B80 and B100) were comparable with properties of diesel oil and ASTM biodiesel standards. Tests have been conducted on CI engine which runs at a constant speed of 1500 rpm, injection pressure of 200 bar, compression ratio 15:1 and 17.5, and varying engine load. The performance parameters include brake thermal efficiency, brake specific energy consumption and emissions parameters such as Carbon monoxide (CO), Hydrocarbon (HC), Oxides of Nitrogen (NOx) and smoke opacity varying with engine load (BP). Diesel engine's thermal performance and emission parameters such as CO, HC, and NOx on different biodiesel blends demonstrate that biodiesel produced from waste cooking oil using heterogeneous catalyst was suitable to be used as diesel oil blends and had lesser emissions as compared to conventional diesel.     

Optimization of biodiesel production from grape seed oil using Taguchi's orthogonal array​

The physicochemical properties of biodiesel are very similar to those of petroleum diesel fuel. The main focus of this study is the production of the biodiesel from grape seed oil. This study shows the optimization of the operation parameters, specifically regarding catalyst concentration, the reaction time, the molar ratio (i.e., methanol-to-oil ratio), and the reaction temperature for the production of biodiesel. The effect of operation factors on performance parameters is analyzed using Taguchi’s orthogonal array. The results depict that 96.90% was the optimum biodiesel yield at a molar ratio 6:1 with a catalyst concentration of 1% by weight and a reaction time of 60 min at 60°C and 4.34 cSt was the optimum biodiesel viscosity at a molar ratio of 6:1 with a catalyst concentration of 0.5% by weight and a reaction time of 75 min at 45°C. The most effective parameter was observed to be catalyst concentration, which conferred 76.39%, and 53.74% of the total influence on the biodiesel yield (Y₁) and viscosity (Y₂), respectively.     

Optimization of biodiesel production from camelina oil using orthogonal experiment

Camelina oil is a low-cost feedstock for biodiesel production that has received a great deal of attention in recent years. This paper describes an optimization study on the production of biodiesel from camelina seed oil using alkaline transesterification. The optimization was based on sixteen well-planned orthogonal experiments (OA₁₆ matrix). Four main process conditions in the transesterification reaction for obtaining the maximum biodiesel production yield (i.e. methanol quantity, reaction time, reaction temperature and catalyst concentration) were investigated. It was found that the order of significant factors for biodiesel production is catalyst concentration > reaction time > reaction temperature > methanol to oil ratio. Based on the results of the range analysis and analysis of variance (ANOVA), the maximum biodiesel yield was found at a molar ratio of methanol to oil of 8:1, a reaction time of 70 min, a reaction temperature of 50 °C, and a catalyst concentration of 1 wt.%. The product and FAME yields of biodiesel under optimal conditions reached 95.8% and 98.4%, respectively. The properties of the optimized biodiesel, including density, kinematic viscosity, acid value, etc., were determined and compared with those produced from other oil feedstocks. The optimized biodiesel from camelina oil meets the relevant ASTM D6571 and EN 14214 biodiesel standards and can be used as a qualified fuel for diesel engines.     

Biodiesel production from Cholrella minutissima microalgae: Kinetic and mathematical modeling

In the present work, a new and pioneering hybrid technology, called hydrodynamic-cavitation reactor, was established and investigated to proof the feasibility for the biodiesel production from Chlorella minutissima microalgae. The process parameters such as inlet pressure (A), molar ratio (B), catalyst concentration (C), and reaction time (D) have been investigated over the biodiesel yield from Chlorella minutissima microalgae. Box–?Behnken design was applied to develop the second- order polynomial model. The error between experimental values and model prediction was found to be less than 10%. Interactive effects of process variables on the biodiesel yield from Chlorella minutissima microalgae was studied using contour graphs. Inlet pressure of 4 bar, molar ratio of 1: 30, catalyst concentration of 1.3%, and reaction time of 40 min produced 99% of biodiesel yield. Further, a kinetic model has also been developed and considers the transesterification reaction to be a second-order reversible, first order with respect to each of the reactants and products. Estimated values of kinetic constants are k₁ = 0.00014 L min/mol and k₂ = 0.035 L min/mol.     

Alkaline catalyzed biodiesel production from safflower (Carthamus tinctorius L.) oil: Optimization of parameters and determination of fuel properties

In this study, the process of biodiesel production from safflower oil was optimized using a single-stage alkaline catalyst (NaOH). The optimization process was carried out depending on parameters, such as catalyst concentration, methanol-oil ratio, reaction temperature, and reaction time. The optimum biodiesel conversion efficiency was obtained to be 93.4% at 0.5% catalyst concentration, 20% methanol-oil ratio, 60 min reaction time, and 60°C reaction temperature. The fuel properties of biodiesel obtained under optimal conditions were determined.     

A supported solid base catalyst synthesized from green biomass ash for biodiesel production

This study aimed to evaluate camphor tree ash (green biomass ash) supported K₂CO₃ as a solid base catalyst for biodiesel production. The catalyst was prepared by way of first-calcination, K₂CO₃ solution impregnation, and second-calcination method. The catalytic performance of the catalyst for the preparation of biodiesel was investigated. Under the optimal conditions of K₂CO₃ loading of 50 wt%, first-calcination temperature of 800°C, second-calcination temperature of 500°C, catalyst concentration of 5 wt%, catalytic time of 210 min, methanol/oil molar ratio of 14:1, and catalytic temperature of 65°C, the biodiesel yield reached 92.27%.     

Optimization of biodiesel production from Annona squamosa seed oil using response surface methodology and its characterization

In the present study, Annona squamosa seed oil has been evaluated as a potential feedstock for biodiesel production. The response surface methodology was used to determine the optimal conditions for the biodiesel production using a central composite design. A quadratic polynomial was developed to predict the response as a function of independent variables and their interactions and only the significant factors affecting the yield were fitted to a second-order response surface reduced 2 factor interaction (2FI) model. Four process variables were assessed at five levels. A biodiesel yield of 98.19% was obtained at optimum conditions: 7.53:1 methanol to oil molar ratio, 1.18 wt% catalyst concentration, reaction temperature of 59.55°C, and reaction time of 47.29 min.     

Performance evaluation of adaptive neuro-fuzzy inference system and response surface methodology in modeling biodiesel synthesis from jatropha–algae oil

Biodiesel production from different feedstocks is an effective method of resolving problems related to the fuel crisis and environmental issues. In this study, an adaptive neuro-fuzzy inference system (ANFIS) and the response surface methodology based Box–Behnken experimental design were used to model the parameters of biodiesel production for a jatropha–algae oil blend, including the molar ratio, temperature, reaction time, and catalyst concentration. A significant regression model with an R² value of 0.9867 was obtained under a molar ratio of 6–12, KOH of 0–2% w/w, time of 60–180 min, and temperature of 35–55°C using response surface methodology (RSM). The ANFIS model was used to individually correlate the output variable (biodiesel yield) with four input variables. An R² value of 0.9998 was obtained in the training. The results demonstrated that the developed models adequately represented the processes they described.     

Transesterification of rapeseed and palm oils in supercritical methanol and ethanol

The results of the rapeseed and palm oils transesterification with supercritical methanol and ethanol were presented. The studies were performed using the experimental setups which are working in batch and continuous regimes. The effect of reaction conditions (temperature, pressure, oil to alcohol ratio, reaction time) on the biodiesel production (conversion yield) was studied. Also the effect of preliminary ultrasonic treatment (ultrasonic irradiation, emulsification of immiscible oil and alcohol mixture) of the initial reagents (emulsion preparation) on the stage before transesterification reaction conduction on the conversion yield was studied. We found that the preliminary ultrasonic treatment of the initial reagents increases considerably the conversion yield. Optimal technological conditions were determined to be as follows: pressure within 20-30 MPa, temperature within 573-623 K. The optimal values of the oil to alcohol ratio strongly depend on preliminary treatment of the reaction mixture. The study showed that the conversion yield at the same temperature with 96 wt.% of ethanol is higher than with 100 wt.% of methanol.     

Optimisation of base-catalysed transesterification of Simarouba glauca oil for biodiesel production

Biodiesel was prepared from the crude oil of Simarouba glauca by transesterification with methanol in the presence of KOH as a catalyst. The reaction parameters such as catalyst concentration, alcohol to oil molar ratio, temperature and rate of mixing were optimised for the production of Simarouba oil methyl ester. The yield of methyl esters from Simarouba oil under the optimal condition was 94–95%. Important fuel properties of methyl esters of Simarouba oil (biodiesel) was compared with ASTM and DIN EN 14214. The viscosity was found to be 4.68 Cst at 40°C and the flashpoint was 165°C.     

Comparison and effect of Cinder supported with Manganese and Lanthanum oxide for biodiesel production

In this study, comparison and effect of Cinder supported with Lanthanum and Manganese oxide as catalyst for transesterification of triglyceride to methyl ester is proposed. The reaction mechanism along with the effects of methanol to oil molar ratio, amount of catalyst to oil, reaction temperature were also discussed. Moreover reusability of catalyst, catalyst resistance toward Free Fatty Acid and water were also discussed. The results show that yield of biodiesel produced with Mn:La:Cinder catalyst was 99% at ≥150 °C in 6 h. Cinder supported with Mn shows conversion of triglycerides from soybean oil in reaction with methanol after 6 h was over 99% at 150 °C. For both catalyst 3wt% of catalyst based on oil, 24:1 methanol/oil molar ratio was reused for 7 times with regeneration. The catalysts displayed great resistance toward 2.5% water and 1% wt fatty acids.     

Thermal chemical enhancement and influence of fluid flow in transesterification of palm oil

This paper presents a model describing the effect of mixing intensity, temperature, and hydrodynamic behavior of transesterification process in a batch continuously stirred tank reactors (CSTR) by using computational fluid dynamics (CFD) and optimization by ASPEN PLUS. The effect of varying temperature from 50, 60 to 65°C and impeller speed ranging from 150, 350 to 700 revolutions per minute (rpm) were investigated using CFD within ANSYS Fluent 12.1. It was found that the mixing efficiency varies with impeller speed from 150 to 350 rpm for maximum biodiesel (BD) yield. Also, the concentration of BD is higher near the impeller due to high turbulence dissipation rate in the zone near the impellers. It was observed that high reactor temperature results in an increased rate of BD production. The optimal BD production was achieved at 60°C. The optimization shows that the BD purity as high as 96.7% was obtained with the molar ratio of methanol to palm oil of 6:1, catalyst amount 1.0 wt%, a reaction temperature of 333 K, and a reaction time of 100 min. The model results were validated against published literature data and good correlation between model results and experimental data was observed. The model can potentially be used as a tool for design and optimization of a batch CSTR in BD production.     

Production and evaluation of biodiesel from mixed castor oil and waste chicken oil

Biodiesel was developed from an unconventional feedstock, i.e. an equivalent blend of castor bean and waste chicken oil through the alkaline-catalyzed transesterification with methanol. The process variables including the alkaline catalyst concentration, methanol to oil molar ratio, reaction temperature, reaction time, and the alkaline catalyst type were investigated. The highest yield of biodiesel (97.20 % ~ 96.98 % w/w ester content) was obtained under optimum conditions of 0.75 % w/w of oil, 8:1 methanol to oil molar ratio, 60°C temperature, and a duration of 30 min. Properties of the produced biodiesel satisfied those specified by the ASTM standards. The results thus indicated that the suggested blend oils are suitable feedstock for the production of biodiesel. The process was found to follow pseudo first-order kinetics, and the activation energy was found to be 8.85 KJ/mole.     

Production of biodiesel at small-scale (10 L) for local power generation

The transesterification reaction of two different types of raw materials, a refined cooking oil and a used cooking sample, was performed at small scale (10 L) at the constant temperature of 65 °C. The effects of several reaction parameters, such as KOH wt% with respect to the oil weight, methanol/oil molar ratio and reaction time, were investigated. Biodiesel yields as good as 97.5 and 93.2% were achieved for the refined and the cooking oils, respectively, in the following conditions: 1.2 wt% of KOH as catalyst, a methanol/oil molar ratio of 6:1 and reaction time of 60 min.The properties of the biodiesel obtained starting from the used cooking oil are as good as those of the biodiesels obeying the European standards. The resulting product was used in a diesel electricity generator engine, which operated in real conditions. The results showed that biodiesel combustion leads to higher concentration of CO and to a lower emission of NO_x as compared to a petrodiesel-fueled engine. An optimization of the operating parameters of the engine would guarantee lower CO emissions in conformity with the regulation.     

Synthesis,characterization, and optimization of Schizochytrium biodiesel production using Na+‐doped nanohydroxyapatite

The present work investigates the synthesis of a new and highly efficient sodium‐doped nanohydroxyapatite, as a heterogeneous catalyst for the production of fatty acid methyl esters from Schizochytrium algae oil. Sodium nitrate supported on nanohydroxyapatite catalyst was prepared using wet impregnation technique and calcinated at different temperatures. The synthesized nanocatalyst was characterized to determine the structural and morphological properties, using BET, XRD, TGA, FTIR, ICP, and TEM. Characterization results reported that the catalyst calcinated at 900°C exhibits good catalytic property. The catalyst was utilized for the production of biodiesel, under different reaction parameters through transesterification process. Response surface methodology (RSM) and artificial neural network (ANN) were employed to evaluate the best combination of molar ratio, catalyst concentration, and reaction time for transesterification process. By using point prediction method, the optimum yield of 96% was achieved at the catalyst concentration of 9.5 wt% of oil, 1:12 molar ratio, and 121‐minute reaction time. The physiochemical properties of the biodiesel were determined, and the result suggested that the biodiesel produced met ASTM D6751 standard. The catalyst exhibits good catalytic performance on reusability up to six runs without the loss of molecular activity. Therefore, the synthesized heterogeneous catalyst derived from animal bone could be efficiently used for the biodiesel production.     

Reaction conditions of ultrasound‐assisted production of biodiesel: A review

Ultrasound‐assisted biodiesel production is an emerging technology that features high energy density, high conversion efficiency, and environment friendliness. This review evaluates the influence of process parameters, including ultrasonic power, ultrasonic frequency, catalyst dosage, alcohol/oil ratio, reaction temperature, reaction time, and alcohol type, on the yield of ultrasonic‐assisted production of biodiesel. Limitations associated with ultrasonic‐assisted production of biodiesel are also analyzed. Further development of this technology is explored. Copyright © 2016 John Wiley & Sons, Ltd.     

Intensification of biodiesel production via ultrasonic-assisted process: A critical review on fundamentals and recent development

Biodiesel is a good alternative fuel to petroleum diesel. It is produced through transesterification reaction between vegetable oil or animal fats and alcohol. The process faces various problems related to the immiscible nature of the reactants causing poor mass transfer rate. This drawback is responsible for long reaction time and low reaction rate leading to an energy intensive process. Process intensification through the use of active catalyst, pressure reactor, high temperature, high stirring rate or even non-conventional approaches such as supercritical method and Biox process often subjects to drawbacks with respect to energy consumption, product quality and reactants cost. This paper highlights recent development in the production of biodiesel under ultrasonic irradiation conditions. It handles the drawback of poor immiscibility between reactants as ultrasonic energy can emulsify the reactants to reduce the catalyst requirement, reaction time and reaction temperature. Ultrasonic energy also neglects the limitations in the use certain feed stocks. Fundamental aspects of the ultrasonic-assisted process using homogeneous and heterogeneous catalysts are reviewed. Recent achievement and future development in this technology in a batch and continuous process are also highlighted.     

Improved transesterification of waste cooking oil into biodiesel using calcined goat bone as a catalyst

In this study, potassium hydroxide-treated animal bones were employed? as a solid heterogeneous catalyst in transesterification of waste cooking oil. This catalyst was characterized by the Fourier-transform infrared spectroscopy (FTIR), and it displayed high-catalytic activity for biodiesel production. Optimum conditions for biodiesel production were catalyst loading 6.0% (w/w) of oil, methanol/oil molar ratio 9:1, calcination temperature 800°C, reaction temperature 65°C, and reaction time of 5 h, which gave maximum biodiesel yield of 84%. Reusability of the catalyst was also confirmed by repeated use of the same catalyst three times without losing much of its activity. Hence, calcined goat bones were found to be a potentially applicable catalyst for biodiesel production at industrial scale.     

A rapid ultrasound-assisted production of biodiesel from a mixture of Karanj and soybean oil

Karanj oil having high free fatty acid was neutralized with a dilute alkali solution and then mixed with soybean oil in different ratios in order to reduce the free fatty acid content significantly. The mixture of the oils was then transesterified with methanol to produce fatty acid methyl ester. The transesterification was carried out using ultrasonication energy of 20 kHz in pulse mode. It was found that up to 60% Karanj oil in the blended mixture could produce good quality biodiesel that met the ASTM standards. However, the lesser content of Karanj oil in the mixture, the lesser the reaction parameters viz. alcohol to oil molar ratio, catalyst concentration, and reaction time. About 99% yield of methyl esters was obtained when the Karanj oil content in the mixture was 20% with a reaction time of 30 min, catalyst concentration 1 wt%, and a temperature of 55°C.