Thermal cracking combined with supercritical fluid extraction of Jordanian oil shale

In this work, supercritical extraction of Jordanian oil shale was investigated experimentally using a batch autoclave device. Operating conditions such as solvent type, mixing time, temperature, pressure, and particle size effects on oil recovery from oil shale have been studied. The results indicated that oil yield increases with the increase of pressure and temperature. The maximum extract yields of 15 and 16 wt% were obtained at 42 bars and 318°C with toluene for El-Lajjun and Sultani shales, respectively. Supercritical fluid extraction (SFE) has shown to be an efficient technique since the extracted yield was 55% more than the yield obtained using the classical Fischer Assay retorting process.     

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.     

Comparison of oil extraction methods,energy analysis and biodiesel production from flax seeds

In recent years, the commercial potential of oil extraction and biodiesel production derived from vegetable seed is being realized. The process energy input requirements are important factors in oil extraction and biodiesel production. This research work investigated oil extraction from flax seeds and compared extraction yield with the energy load. The effect of moisture content on the oil yield was compared between a mechanical oil expeller, organic solvent extraction, organic solvent and microwave assisted, organic solvent and ultrasonic assisted, and combined microwave and ultrasonic with organic solvent. The maximum oil yields % wt/wt from these techniques was 22.6%, 36.3%, 10.0%, 42.0% and 27.8%, respectively. The moisture content had a significant effect on oil yield with the mechanical oil expeller, organic solvent method and ultrasonic assisted extraction, whereas no or little effect was found on microwave‐assisted extraction. The microwave‐assisted extraction showed better results compared with the ultrasonic‐assisted and combined treatment methods. The relative energy consumption of these processes was experimentally investigated; energy ratios were calculated based on the amount of energy recovered to the amount of energy supplied to the flax seed for oil extraction. The net energy ratios showed that microwave‐assisted extraction had the highest (25.21%), followed by organic solvent method (14.04%), ultrasonic method (6.33%) and lowest was with combined ultrasonic and microwave assisted treatment (5.73%). These results showed that flax seed oil can be extracted using microwave‐assisted methods efficiently and in an energy feasible manner. In situ ultrasonic transesterification was applied to powdered samples with 4%, 8% and 12% moisture content (on % dry basis) within an ultrasonic bath having an intensity of 0.124 W/cm². The flax seed biodiesel produced showed a highest conversion yield of 93%, and the effect of different moisture content on the yield showed that 4% moisture content sample produced the greatest biodiesel yield. Copyright © 2013 John Wiley & Sons, Ltd.     

Characterization of Crude Oils and Their Fouling Deposits Using a Batch Stirred Cell System

A small (1 L) batch stirred cell system has been developed to study crude oil fouling at surface temperatures up to 400°C and pressures up to 30 bar. Fouling resistance–time data are obtained from experiments in which the principal operating variables are surface shear stress, surface temperature, heat flux, and crude oil type. The oils and deposits are characterized and correlated with the experimental heat transfer fouling data to understand better the effects of process conditions such as surface temperature and surface shear stress on the fouling process. Deposits are subjected to a range of qualitative and quantitative analyses in order to gain a better insight into the crude oil fouling phenomenon. Thermal data that can be obtained relatively quickly from the batch cell provide fouling rates, Arrhenius plots, and apparent activation energies as a function of process variables. The experimental system, supported by computational fluid dynamics (CFD) studies, allows fouling threshold conditions of surface temperature and shear stress to be identified relatively quickly in the laboratory. The data also contribute to existing knowledge about the compensation plot.     

Response surface analysis for optimisation of reaction parameters of biodiesel production from alcoholysis of Parinari polyandra seed oil

Availability of information on the efficiency of applied conditions to biodiesel synthesis from diverse seed oil can establish optimal biodiesel yield from favourable reaction variables. The effect of reaction parameters; temperature, time and catalyst amount, were varied on biodiesel yield from alcoholysis of Parinari polyandra oil using potassium hydroxide as catalyst. Maximum biodiesel yield of 95.62% was obtained from the experimental results. Analysis of Variance revealed that the reaction variables had significant effects on biodiesel yield. Data analysis predicted an optimal biodiesel yield of 92.75% at reaction conditions of 61.20°C temperature, 60 min, and 1?wt% of catalyst amount. Validation experiments of the optimal conditions gave an average biodiesel yield of 91.72%. The study established optimal conditions of temperature, time, and catalyst amount for biodiesel production from P. polyandra oil. The fuel properties of the biodiesel fell within the standards of the American Society for Testing and Materials D6751.     

Co-liquefaction of Yatağan lignite and waste tire under catalytic conditions. Part 1. Effect of fresh tetraline and recycled tetraline on the conversion

In this study, the effect of solvent type and the solvent/solid ratio on the liquefaction of Mu?la-Yatagan lignite (YL) combined with waste tire (WT) under catalytic conditions investigated. Liquefaction experiments carried out the following conditions, a reaction temperature of 400°C, a catalyst concentration of 3%, solvent/solid ratio from 1/1 to 9/1, reaction time of 90 min, lignite/waste ratio of 1/1. In addition, mixing speed was 400 rpm, and the nitrogen gas pressure fixed at 30 bar. After the each of liquefaction experiments finished, the soluble products (SP) classified as preasphaltene (PAS), asphaltene (AS) and oil+gas (OG), by solvent extraction. Due to the optimum total conversion determined, fresh tetraline obtained as the most favorable solvent with 71.71%, for the liquefaction of YL with WT. However, the total conversion for recycling tetraline is 68.6%. According to the results, co-liquefaction of YL combined with WT using recycle solvent is the one way to offer, alternatively of using crude oil, producing SP for not crude oil, producing SP for not only fuel-oil production but also prefer chemical raw materials. With respect to the optimum oil+gas yield results, the most convenient solvent type and the solvent/solid ratio are the recycled solvent and its 3/1 ratio.     

Enhancing the production of biofuels from cottonseed oil by fixed-fluidized bed catalytic cracking

The production of biofuels from cottonseed oil by fixed-fluidized bed catalytic cracking at ambient pressure was studied. The effect of reaction temperature (400–500 °C), catalyst-to-oil ratio (6–10)and residence time (50–90 s) were studied over the yields of bio-gasoline and light fuel oil (≤360 °C). Design of experiments was used to study the effect of operating conditions over yield of hydrocarbon fuel. The response surface methodology was used to determine the optimum values of the operating variables for maximum yield of biofuels in the liquid product obtained.     

Application of response surface methodology for optimizing transesterification of Moringa oleifera oil: Biodiesel production

Response surface methodology (RSM), with central composite rotatable design (CCRD), was used to explore optimum conditions for the transesterification of Moringa oleifera oil. Effects of four variables, reaction temperature (25–65 °C), reaction time (20–90 min), methanol/oil molar ratio (3:1–12:1) and catalyst concentration (0.25–1.25 wt.% KOH) were appraised. The quadratic term of methanol/oil molar ratio, catalyst concentration and reaction time while the interaction terms of methanol/oil molar ratio with reaction temperature and catalyst concentration, reaction time with catalyst concentration exhibited significant effects on the yield of Moringa oil methyl esters (MOMEs)/biodiesel, p < 0.0001 and p < 0.05, respectively. Transesterification under the optimum conditions ascertained presently by RSM: 6.4:1 methanol/oil molar ratio, 0.80% catalyst concentration, 55 °C reaction temperature and 71.08 min reaction time offered 94.30% MOMEs yield. The observed and predicted values of MOMEs yield showed a linear relationship. GLC analysis of MOMEs revealed oleic acid methyl ester, with contribution of 73.22%, as the principal component. Other methyl esters detected were of palmitic, stearic, behenic and arachidic acids. Thermal stability of MOMEs produced was evaluated by thermogravimetric curve. The fuel properties such as density, kinematic viscosity, lubricity, oxidative stability, higher heating value, cetane number and cloud point etc., of MOMEs were found to be within the ASTM D6751 and EN 14214 biodiesel standards.     

Muskmelon (Cucumis melo) seed oil: A potential non-food oil source for biodiesel production

Methanolysis of muskmelon seed oil was optimized employing RSM (response surface methodology). Four process variables were evaluated at two levels: methanol/oil molar ratio (3:1–12:1), catalyst concentration in relation to oil mass (0.25–1.25 wt % KOH), reaction temperature (25–65 °C) and methanolysis reaction time (20–90 min). Multiple regression analysis was employed to get the quadratic polynomial equation for predicting transesterification using RSM. The result indicated that catalyst concentration and reaction temperature were the important factors that significantly affect the yield of MMOMEs (muskmelon oil methyl esters)/biodiesel. The RSM methodology was used to obtain methyl esters yield (89.5%) were found at following reaction conditions; 5.8:1 methanol-to-oil ratio, 0.79% catalyst concentration, 55 °C reaction temperature and 72.5-min reaction time. There was a linear correlation between observed and predicted values. The biodiesel was analyzed using GC/MS (gas chromatography/mass spectrometry) which indicated four FAMEs (fatty acid methyl esters) (linoleic-, oleic-, palmitic- and stearic acids) as its major components. The FT-IR (fourier transform infraRed) spectrum of MMOMEs was also acquired to ensure the confirmation of methyl esters formation. Fuel properties of MMOMEs were determined and found to satisfy the ASTM D 6751 and EU 14214 specifications.     

Jatropha curcus: a renewable source of energy for meeting future energy needs

The Jatropha seed was extracted by solvent extraction with petroleum ether. The oil yield was 37.4% on a whole seed basis and 46.0–48.6% from the kernel. The fatty acid composition, its important properties and potential as a petroleum substitute are discussed.     

Optimization of biodiesel produced from watermelon (Citrullus vulgaris) using batch-type production unit

In the present work the production of a biodiesel from watermelon seed oil (Citrullus vulgaris) by methanol-induced transesterification using an alkaline catalyst (potassium hydroxide, KOH) has been examined. The influence of the operating variables such as agitation speed, temperature, reaction time, alcohol amount, and catalyst concentration was determined experimentally and found to be 550 rpm agitation rate, 60°C reaction temperature, 55 min reaction time, 20% of methanol, and 13 g of catalysts concentration for 2.5 liters of oil. The yield of biodiesel from the watermelon methyl ester (WME) under optimized conditions is found to be 91%. The properties of biodiesel are measured as per ASTM standards and compared with the base diesel.     

Production of crude bio-oil via direct liquefaction of spent K-Cups

Spent K-Cups were liquefied into crude bio-oil in a water-ethanol co-solvent mixture and reaction conditions were optimized using response surface methodology (RSM) with a central composite design (CCD). The effects of three independent variables on the yield of crude bio-oil were examined, including the reaction temperature (varied from 255 °C to 350 °C), reaction time (varied from 0 min to 25 min) and solvent/feedstock mass ratio (varied from 2:1 to 12:1). The optimum reaction conditions identified were 276 °C, 3 min, and solvent/feedstock mass ratio of 11:1, giving a mass fraction yield of crude bio-oil of 60.0%. The overall carbon recovery at the optimum conditions was 93% in mass fraction. The effects of catalyst addition (NaOH and H₂SO₄) on the yield of crude bio-oil were also investigated under the optimized reaction conditions. The results revealed that the presence of NaOH promoted the decomposition of feedstock and significantly enhanced the bio-oil production and liquefaction efficiency, whereas the addition of H₂SO₄ resulted in a negative impact on the liquefaction process, decreasing the yield of crude bio-oil.     

Enhancement in Jatropha-based biodiesel yield by process optimisation using design of experiment approach

Edible and non-edible oils are used for the production of biodiesel from the last so many years and these oils are extracted from their respective seeds. Jatropha oil is used as a feedstock to produce biodiesel for running the Compression Ignition engine. A statistical model is developed to interrelate the trans-esterification process variables for the biodiesel yield using design of experiment approach by selecting central composite design of a response surface methodology. Results shown in this paper indicate that the optimum observed yield of 95.5% has the following reaction conditions: Molar ratio 19.84 (% v/v), reaction time 3 h, reaction temperature 70°C, catalyst concentration 4.18 wt% and stirrer rpm 650. Also, the yield produced is higher when compared with 93.5% which was observed by Lee paper using the same methodology. Moreover, the fuel properties of Jatropha biodiesel are closer to the ASTM standard of biodiesel.     

Effect of Assistants in Refining Coker Gas Oil with Furfural

Abstract

In order to improve furfural's solubility and selectivity in refining the coker gas oil, two kinds of assistants (A and B) were chosen in this test and used to investigate the effects on yield of the refined oil and removal rate of the basic nitrogen. Based on the industrial operation condition, we choose 60°C as the extraction temperature, and from the intermittent test in laboratory, the laboratorial result shows that the yield of refined oil increased considerably and the removal rate of the basic nitrogen enhanced greatly after adding the assistant A under the little rate of solvent/oil. When the ratio is 0.5, adding 4% of assistant into solvent, the yield of refined oil and the removal rate of the basic nitrogen increased by 3.86 and 9.10%, respectively. In contrast, the assistant B has good effects on that under the big ratio of solvent/oil, especially on the ability of the removal of basic nitrogen compound.     

Low cost production of ester from non edible oil of Argemone mexicana

This paper contains details extracting esters from oil of Argemone mexicana using transesterification technique. However, weed crops as A. mexicana seed oil and its seed oil methyl ester have not been tested for their production potential, comparative fuel qualities with diesel and economic feasibility. The average oil yield has been found 35%. To the author's best knowledge, this is the first study on A. mexicana seed oil and methyl ester production as a fuel. In this study, A. mexicana crop pattern and potential of seed production in field conditions, oil extraction process from the seeds and the transesterification process for ester production were examined. Seeds were collected from the crop, which was grown over a selected land area. A. mexicana seed oil was extracted and its physical and chemical characteristics determined. The produced A. mexicana seed oil methyl ester was characterized by exposing its major properties. Methyl ester yield, fuel properties and economic assessment of the oil and its methyl ester were determined and compared to that of commercial diesel fuel. The analysis of the properties in comparison to commercial diesel fuel showed that transe-methylation improve the fuel properties of the oil.     

Biodiesel production from Cannabis sativa oil from Pakistan

The present study was appraised using response surface methodology for process optimization owing to strong interaction of reaction variables: NaOCH₃ catalyst concentration (0.25–1.50%), methanol/oil molar ratio (3:1–9:1), reaction time (30–90 min), and reaction temperature (45–65°C). The quadratic polynomial equation was determined using response surface methodology for predicting optimum methyl esters yield from Cannabis sativa oil. The analysis of variance results indicated that molar ratio and reaction temperature were the key factors that appreciably influence the yield of Cannabis sativa oil methyl esters. The significant (p < 0.0001) variable interaction between molar ratio × catalyst concentration and reaction time × molar ratio was observed, which mostly affect the Cannabis sativa oil methyl esters yield. The optimum Cannabis sativa oil methyl esters yield, i.e., 86.01% was gained at 53°C reaction temperature, 7.5:1 methanol/oil molar ratio, 65 min reaction time, and 0.80% catalyst concentration. The results depicted a linear relationship between observed and predicted values. The residual analysis predicted the appropriateness of the central composite design. The Cannabis sativa oil methyl esters, analyzed by gas chromatography, elucidated six fatty acid methyl esters (linoleic, α-linolenic, oleic, palmitic, stearic, and γ-linolenic acids). In addition, the fuel properties, such as kinematic viscosity at 40°C; cetane number; acid value; flash point; cloud, pour, and cold filter plugging points; ash content; density; and sulphur content, of Cannabis sativa oil methyl esters were evaluated and discussed with reference to ASTM D 6751 and EU 14214 biodiesel specifications.     

Hydrogen transfer during co-liquefaction of Elbistan lignite and biomass: liquid product characterization approach

In this study, Elbistan lignite (EL) and manure were liquefied under catalytic conditions in an inert atmosphere. Red mud, tetralin, and distilled water were used as a catalyst and solvent, respectively. The liquefaction studies were carried out under catalytic conditions in the catalyst concentration of 9%, solvent/solid ratio of 3/1, reaction time of 60 min, waste/lignite ratio of 1/3, and at temperature of 400°C. Stirring speed and initial nitrogen pressure were kept constant at 400 rpm and 20 bar, respectively. At the end of liquefaction process, the soluble liquefaction products were separated by successive solvent extraction to preasphaltene, asphaltene, and oils. Oil products characterized by H-NMR to be able to differ hydrogen transfer from manure to EL surface. To obtain the hydrogen transfer way, liquefaction experiments conducted under inert atmosphere which does not related to hydrogen reaction, other above experimental conditions were kept same but only solvent type changed. The reason of using distilled water instead of tetraline is tetraline known as hydrogen donor but not water. Because water behaves supercritical conditions during the liquefaction stage. EL liquefied alone while using tetraline however EL liquefied with manure with using distilled water as a solvent. The obtained oil products form both experiments characterized by H-NMR. The radical groups diffraction and range values are not changed significantly shows that manure behaved as an hydrogen donor. So, EL with manure is the one great option to reduce cost of hydrogen source for direct coal liquefaction plant.     

Effect of natural antioxidants on the oxidation stability of methyl ester of rubber seed oil

Biodiesel has been proved as a promising solution amidst other alternate fuels in terms of its characteristics compared to diesel. The oxidation property of biodiesel results in the degradation of its quality. This problem can be solved by the addition of suitable antioxidants which improves the oxidation stability of the fuel. Usage of natural antioxidants offsets the defects in synthetic antioxidants, because they are renewable, nontoxic as well as cost effective. The effect of natural antioxidant additives on the oxidation stability of the Methyl Ester of non-edible Rubber Seed oil (MERB) has been experimentally investigated in this study. Natural antioxidants Ginger, Moringa oleifera Lam, Basil and Oregano have been mixed in varying proportions (500, 1000, 1500 and 2000 ppm) and the antioxidant characteristics of the additives were identified by using Fourier Transform Infra-Red (FTIR) analysis. The induction period, which denotes the oxidation stability was worked out with Rancimat apparatus. From this study it was found out that the oxidation stability of MERB increased when natural antioxidant additives were added. Among the antioxidants used, Ginger was found to be more effective in enhancing the oxidation stability, with induction period values of 11.5 h, 18.5 h, 23 h and 26.5 h for proportions 500, 1000, 1500 and 2000 ppm respectively.     

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.     

Optimization of transesterification process parameters of castor oil ethanolysis using response surface methodology-based genetic algorithm

Castor oil is unusual oil that is predominantly composed of ricinoleic acid. In the present study, castor oil biodiesel was produced from castor oil with bio-alcohol (ethanol) via a transesterification process. Also, this study investigates the influence of transesterification process parameters, i.e., reaction temperature, catalyst (sodium ethoxide) concentration, and ethanol:castor oil molar ratio on the yield of castor oil ethyl ester. The experiments are carried our as per a central composite design. A second-order response surface model was developed to predict the yield of castor oil ethyl ester as a function of transesterification process parameters. The developed models indicated that the predicted values are well in agreement with the experimental results. Finally, optimization of transesterification process parameters was carried out using a response surface methodology-based genetic algorithm. The optimization results indicated a reaction temperature of 41°C, catalyst concentration of 1.25% w/w of oil, and ethanol to oil molar ratio of 18.42 for achieving a higher yield of castor oil ethyl ester of 93.9%.