Developing technologies for the production of alternative fuels from biorenewable resources is a field of interest for many researchers. Adequate substitute to diesel fuel is biodiesel that is ...synthesized through the transesterification of vegetable oils or animal fats and fulfilled the international standards. Ionic liquids (ILs) and deep eutectic solvents (DESs) have gained tremendous attention for their use in biodiesel production because of environmental benefits and process improvements. The present work overviews the use of ILs and DESs in the reaction and purification steps of biodiesel production processes where they are used as catalysts, cosolvents and extracting solvent. In addition, the possibilities of recycling and reusing of ILs and DESs are pointed out. Moreover, optimization and kinetic studies of biodiesel synthesis in the presence of ILs or DESs are discussed. The use of novel technologies combined with ILs or and DESs are also considered. Therefore, the present paper highlights the promising uses of ILs and DESs in biodiesel production in the future.
The present paper is an overview of the recent progress in the development of various CaO-based catalysts suitable for biodiesel production. The mechanism, kinetics and optimization of ...transesterification reaction over these catalysts are first considered. Then, the practical application of CaO-based catalysts is discussed with a special stress on leaching and reusability of these catalysts. Also, various continuous reactor systems currently in use for biodiesel production are appraised. In addition to it, purification of crude biodiesel and the ecological aspects of using CaO-based catalysts are considered. Finally, the potentials of CaO-based catalysts for heterogeneous catalysis for biodiesel production are emphasized to assess the future perspectives of their use. This review might help in selecting suitable CaO-based catalysts and the optimum reaction conditions for biodiesel production.
In the present paper state-of-the art and perspectives of ultrasound-assisted (UA) biodiesel production from different oil-bearing materials using acid, base and enzyme catalysts are critically ...discussed. The ultrasound action in biodiesel production is primarily based on the emulsification of the immiscible liquid reactants by microturbulence generated by radial motion of cavitation bubbles and the physical changes on the surface texture of the solid catalysts generating new active surface area. The importance of ultrasound characteristics and other process variables for the biodiesel yield and the reaction rate is focused on. UA transesterification is compared with other techniques for biodiesel production. Several different developing methods reducing the biodiesel production costs such as the optimization of process factors, the development of the process kinetic models, the use of phase transfer catalysts, the application of the continuous process, the design of novel types of ultrasonic reactors and the in situ ultrasound application in transesterification of oily feedstocks are also discussed.
•Synthesis of vishnevite-type zeolite-like material (ZM) from waste fly ash (FA).•Use of waste chicken eggshell as an active component in the CaO/FA-ZM catalyst.•Methanol/oil molar ratio of 6:1 was ...found optimal in methanolysis over CaO/FA-ZM.•FAME content of 97.5% was achieved for 1 h under moderate reaction conditions.•Kinetics based on changing mechanism and TAG mass transfer limitation was proven.
The present paper is focused on the development of a new environment-friendly methanolysis catalyst completely based on waste materials: lignite coal fly ash and chicken eggshells. A novel catalyst based on CaO supported on a fly ash-based zeolitic material (CaO/FA-ZM) was obtained from a cancrinite-sodalite group zeolite-like material (vishnevite type) and active CaO by alkali activation in a new miniature autoclave reactor system and hydration-dehydration. Agitation by rotation of the entire reaction mixture led to a more homogeneous zeolitic product and saved both time and energy. The obtained catalyst structure corresponds to gismondine and the crystallographic modification of calcium silicate (α’-dicalcium silicate) with deposited CaO. The characteristics of the synthesized catalyst were determined using ED-XRF, XRD, FT-IR, SEM, Hg-porosimetry, N2-physisorption, LDPSA, and Hammett indicators. The CaO/FA-ZM catalyst exhibited a high activity (97.8% of FAME for only 30 min) and stability (a negligible drop in activity in five consecutive cycles) in the methanolysis reaction under the optimal reaction conditions (temperature of 60 °C, methanol/oil molar ratio of 6:1, and catalyst concentration of 6 wt%). A kinetic study was performed using two different mechanisms: the irreversible pseudo-first-order reaction mechanism in two regimes (heterogeneous and homogeneous) and the changing mechanism combined with the triacylglycerol mass transfer limitation. Both models showed a satisfactory agreement between the experimental and predicted values of conversion degree (R2 > 0.93), confirming their validity for the CaO-based heterogeneously catalyzed methanolysis. The values of the activation energy calculated for both mechanisms were 67.17 and 58.03 kJ mol−1, respectively.
•CaO-rich catalyst obtained from palm kernel shell biochar (PKSB) has promising potential for biodiesel production.•Sunflower oil methanolysis catalyzed by PKSB-based catalyst is optimized.•Optimum ...reaction conditions ensure the best FAME content of 99%.•Reaction rate law is changing- and first-order with respect to TAG and FAME.•PKSB catalyst can be reused without any treatment in three consecutive cycles.
Sunflower oil methanolysis over CaO-based palm kernel shell biochar (PKSB) catalyst was assessed by coupling full factorial design with modeling, optimization and kinetic studies. According to the analysis of variance, the effect of reaction temperature and methanol-to-oil molar ratio on the fatty acid methyl ester (FAME) synthesis is significant, while the effect of catalyst loading is statistically negligible. The optimum reaction conditions are found to be catalyst loading of 3wt%, temperature of 65°C and methanol-to-oil molar ratio of 9:1, ensuring the best FAME content of 99%. The kinetic model of the methanolysis of sunflower oil, catalyzed by PKSB-based catalyst, combines the changing- and first-order reaction rate laws with respect to triacylglycerols and FAMEs, respectively. The high activation energy (108.8kJ/mol) indicates the temperature sensitivity of the reaction. The CaO-based PKSB catalyst can be reused without any treatment in three consecutive cycles with no significant drop in activity. Since the calcium content in the biodiesel product is higher than the standard limit, the overall process should include a purification stage.
► Ethanolysis of vegetable oils used for biodiesel production. ► Biodiesel as a completely agricultural fuel consisted of fatty acid ethyl esters. ► Review on development and optimization of ...ethanolysis process. ► Kinetics models describing the ethanolysis process rate. ► Possibilities for improving the ethanolysis process.
At present, the homogeneous base-catalyzed methanolysis reaction of vegetable oils is a most often used process for the industrial biodiesel production. The toxicity of methanol, the risk of the methanol vapor explosion and the possibility of the ethanol production from biorenewable resources have contributed to the development of a vegetable oil ethanolysis process for the biodiesel production. In the reaction of vegetable oils and ethanol in the presence of a catalyst, completely agricultural fuels consisted of fatty acid ethyl esters (FAEE) are obtained having physico-chemical properties similar to those of the appropriate methyl esters and diesel fuel. The ethanolysis reaction of various oily feedstocks has been widely studied to optimize the reaction conditions and to develop new catalytic systems and processes based on chemical and biological catalysts, as well as the development of non-catalytic processes. Most researches investigate the application of homogeneous base catalysts. This paper studies the review of vegetable oil ethanolysis investigations for the biodiesel production done so far. The goals of the paper are to present the development of FAEE synthesis by catalytic and non-catalytic processes, their advantages and disadvantages, the influence of some operating and reaction conditions on the process rate and ethyl esters yield, the kinetics models describing the ethanolysis process rate, the process optimization and the possibilities for improving the FAEE synthesis process.
•Biodiesel is produced from the oil obtained from waste plum kernel stones.•Esterification of FFA in the oil is optimized by RSM combined with CCD.•The pseudo-first order kinetic model of the FFA ...esterification is developed.•CaO-catalyzed methanolysis of the esterified oil is used in the second step.
This study reports on the use of oil obtained from waste plum stones as a low-cost feedstock for biodiesel production. Because of high free fatty acid (FFA) level (15.8%), the oil was processed through the two-step process including esterification of FFA and methanolysis of the esterified oil catalyzed by H2SO4 and CaO, respectively. Esterification was optimized by response surface methodology combined with a central composite design. The second-order polynomial equation predicted the lowest acid value of 0.53mgKOH/g under the following optimal reaction conditions: the methanol:oil molar ratio of 8.5:1, the catalyst amount of 2% and the reaction temperature of 45°C. The predicted acid value agreed with the experimental acid value (0.47mgKOH/g). The kinetics of FFA esterification was described by the irreversible pseudo first-order reaction rate law. The apparent kinetic constant was correlated with the initial methanol and catalyst concentrations and reaction temperature. The activation energy of the esterification reaction slightly decreased from 13.23 to 11.55kJ/mol with increasing the catalyst concentration from 0.049 to 0.172mol/dm3. In the second step, the esterified oil reacted with methanol (methanol:oil molar ratio of 9:1) in the presence of CaO (5% to the oil mass) at 60°C. The properties of the obtained biodiesel were within the EN 14214 standard limits. Hence, waste plum stones might be valuable raw material for obtaining fatty oil for the use as alternative feedstock in biodiesel production.
Biodiesel production from corn oil: A review Veljković, Vlada B.; Biberdžić, Milan O.; Banković-Ilić, Ivana B. ...
Renewable & sustainable energy reviews,
08/2018, Letnik:
91
Journal Article
Recenzirano
This paper deals with biodiesel production from corn oil as a feedstock via the transesterification and esterification reactions. To date, corn oil has not been considered a viable biodiesel ...feedstock because of its high edible value and relatively high price, but some industrial corn processing co-products, such as corn germ and dried distillers grains with solubles (DDGS), have potential for this application after the extraction of corn distillers oil (CDO). Here, after brief discussion of the issues related to corn botany, cultivation, and use, as well as the corn germ and oil composition, properties and use, the methods of corn processing for germ and DDGS recovery are presented. In addition, the mechanical and solvent extraction techniques for oil recovery from whole ground corn kernels, germs, and DDGS are considered. Furthermore, biodiesel production from corn oil, waste frying corn oil, and CDO is critically analyzed. It is expected that further investigation will be directed toward developing simpler, more effective and energy-saving technologies for biodiesel production from corn oil-based feedstocks, especially from CDO. The integration of biodiesel production directly into corn-based ethanol production will advance the overall economy of industrial plants. Furthermore, the fuel properties, performances and exhaust gas emissions of corn-based biodiesel and its blends with diesel fuel are discussed, taking into account the biodiesel quality standards. Finally, issues related to the environmental and socio-economic impacts of corn-based biodiesel production and use are also tackled.
•Oily co–products of industrial corn processing are promising biodiesel feedstocks.•“Green” oil extraction methods will improve corn oil recovery.•Simpler, more efficient and energy–saving corn-based biodiesel technology is needed.•The integrated reactor/separation process of biodiesel production is more efficient.•Biodiesel production can be integrated in the corn-based ethanol production.
Biodiesel production from non-edible plant oils BANKOVIC-ILIC, Ivana B; STAMENKOVIC, Olivera S; VELJKOVIC, Vlada B
Renewable & sustainable energy reviews,
08/2012, Letnik:
16, Številka:
6
Journal Article
Recenzirano
Because of biodegradability and nontoxicity biodiesel has become more attractive as alternative fuel. Biodiesel is produced mainly from vegetable oils by transesterification of triacylglycerols. From ...economic and social reasons, edible oils should be replaced by lower-cost and reliable feedstocks for biodiesel production such as non-edible plant oils. This paper reviews various methods for biodiesel production from common non-edible oils employing alcoholysis reactions. The aim of this paper is to present the possibilities of the use of non-edible oils into biodiesel production, to consider the various methods for treatment of non-edible oils and to emphasize the influence of the operating and reaction conditions on the process rate and the ester yield. The special attention is paid to the possibilities of optimization, kinetics and improvement of biodiesel production from non-edible oils.
This paper overviews the technological, technical, economic, environmental, social, toxicological and human health risk considerations of biodiesel production and use. The future efforts in the ...technological domain should be directed towards low–cost and non–edible feedstocks, advanced technologies with reduced overall production costs and profitable production capacity. Process innovations that include new more active and stable catalysts, advanced reactors, continuous operation, lower energy inputs, better energy balance and lower GHG emissions and produce low or no wastes can lead to more efficient biodiesel production. Environmentally sustainable biodiesel production requires that sustainability standards cover direct and indirect impacts on the environment, i.e. soil, water and air. The combination of technological with economic, social and environmental issues will increase biodiesel benefits and may lead to integrated biorefineries capable of producing sustainable biodiesel and other valuable chemicals. Government policies will be the primary driving force for further increases in biodiesel production. Increased cooperation among governments and various stakeholders is needed to develop and apply corresponding sustainability criteria in a consistent way worldwide as soon as possible.
