Submit to Energies Review for Energies Propose a Special Issue

Journal Menu

Journal Browser

► Journal Browser

Optimization of Biodiesel and Biofuel Process

Print Special Issue Flyer
Special Issue Editors
Special Issue Information
Keywords
Benefits of Publishing in a Special Issue
Published Papers

A special issue of Energies (ISSN 1996-1073). This special issue belongs to the section "A4: Bio-Energy".

Deadline for manuscript submissions: closed (20 October 2020) | Viewed by 32784

Printed Edition Available!
A printed edition of this Special Issue is available here.

Special issue Optimization of Biodiesel and Biofuel Process book cover image

Share This Special Issue

Special Issue Editors

Prof. Dr. Diego Luna

E-Mail Website
Guest Editor

Departamento de Química Orgánica, Instituto de Química Fina y Nanoquímica, Universidad de Córdoba, Campus de Excelencia Internacional Agroalimentario CeiA3. Edificio Marie Curie, E 14014 Córdoba, Spain
Interests: heterogeneous catalysis; green chemistry; biorefinery; renewable raw materials biotechnology; transesterification; biodiesel; biodiesel-like biofuels; eco diesel; lipases; additives; oxygenated additives
Special Issues, Collections and Topics in MDPI journals

Dr. Antonio Pineda

E-Mail Website
Guest Editor

Departamento de Química Orgánica, Universidad de Córdoba, Edificio Marie Curie (C-3), Ctra Nnal IV-A, Km 396, E14014 Cordoba, Spain
Interests: heterogeneous catalysis; biomass valorization; flow chemistry; mechanochemistry
Special Issues, Collections and Topics in MDPI journals

Dr. Rafael Estevez

E-Mail Website
Guest Editor

Departamento de Química Orgánica, Instituto Universitario de Investigación en Química Fina y Nanoquímica (IUNAN), Universidad de Córdoba, Campus de Rabanales, Edificio Marie Curie, E-14071 Córdoba, Spain
Interests: heterogeneous catalysis; glycerol valorization; biofuels; bioadditives; microwave-assisted processes
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Although the compression ignition (C.I.) engine, invented by Rudolf Diesel, was originally intended to work with pure vegetable oils as fuel, more than a century ago it was adapted to be used with a fuel of fossil origin, obtained from oil. Therefore, there would be no technical difficulties to return to the primitive design of using biofuels of renewable origin, such as vegetable oils. The main drawback is found in the one billion C.I. engines which are currently in use, which would have to undergo a modification in the injection system in order to adapt them to the higher viscosity of vegetable oils in comparison to that of fossil fuel. Thus, the gradual incorporation of biofuels as substitutes of fossil fuels is mandatory.

This Special Issue aims to collect works that provide different technical solutions to make possible the smooth transition from the current state, in which diesel engines operate with fossil fuels, to a new situation in which diesel engines will work employing solely renewable biofuels. Thus, in addition to conventional biodiesel, obtained by catalytic or enzymatic transesterification of triglycerides, all research providing effective solutions to allow the use of fats and oils as biofuels in diesel engines, without having to perform any modification in them, will be welcomed. This Special Issue also aims to collect studies related but not limited to the production and engineering development of alternative high-quality biofuels from vegetable oils, obtained by the hydrotreating of triglycerides (green diesel), the production of novel biofuels that integrate glycerol in their composition, as well as the development of diesel and biodiesel additives. These biofuels seek to achieve 100% atom efficiency, because neither glycerol nor any byproduct is obtained. Thus, the overall production process of the biofuel is simplified to a great extent.

Prof. Dr. Diego Luna
Dr. Antonio Pineda
Dr. Rafael Estevez
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Energies is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

transesterification
biodiesel
alkaline catalysis
acid catalysis
hydrotreating of triglycerides
green diesel
biodiesel-like biofuels
Gliperol
DMC-BioD
EcoDiesel
lipases
additives

Benefits of Publishing in a Special Issue

Ease of navigation: Grouping papers by topic helps scholars navigate broad scope journals more efficiently.
Greater discoverability: Special Issues support the reach and impact of scientific research. Articles in Special Issues are more discoverable and cited more frequently.
Expansion of research network: Special Issues facilitate connections among authors, fostering scientific collaborations.
External promotion: Articles in Special Issues are often promoted through the journal's social media, increasing their visibility.
e-Book format: Special Issues with more than 10 articles can be published as dedicated e-books, ensuring wide and rapid dissemination.

Further information on MDPI's Special Issue polices can be found here.

Published Papers (9 papers)

Download All Papers

Order results

Result details

Show export options Show export options

Select all

Export citation of selected articles as:

Editorial

Jump to: Research, Review

4 pages, 195 KiB

Open AccessEditorial

Optimization of Biodiesel and Biofuel Process

by Diego Luna and Rafael Estevez

Energies 2022, 15(16), 5917; https://doi.org/10.3390/en15165917 - 15 Aug 2022

Cited by 4 | Viewed by 1316

Abstract

Currently in the European Union (EU) there is an intense debate on the limits to acquire the European Green Deal, to make Europe the first climate neutral continent in the world [...] Full article

(This article belongs to the Special Issue Optimization of Biodiesel and Biofuel Process)

Research

Jump to: Editorial, Review

14 pages, 1762 KiB

Open AccessArticle

Outlook for Direct Use of Sunflower and Castor Oils as Biofuels in Compression Ignition Diesel Engines, Being Part of Diesel/Ethyl Acetate/Straight Vegetable Oil Triple Blends

by Laura Aguado-Deblas, Rafael Estevez, Jesús Hidalgo-Carrillo, Felipa M. Bautista, Carlos Luna, Juan Calero, Alejandro Posadillo, Antonio A. Romero and Diego Luna

Energies 2020, 13(18), 4836; https://doi.org/10.3390/en13184836 - 16 Sep 2020

Cited by 20 | Viewed by 3002

Abstract

Today, biofuels are indispensable in the implementation of fossil fuels replacement processes. This study evaluates ethyl acetate (EA) as a solvent of two straight vegetable oils (SVOs), castor oil (CO), and sunflower oil (SO), in order to obtain EA/SVO double blends that can be used directly as biofuels, or along with fossil diesel (D), in the current compression-ignition (C.I.) engines. The interest of EA as oxygenated additive lies not only in its low price and renewable character, but also in its very attractive properties such as low kinematic viscosity, reasonable energy density, high oxygen content, and rich cold flow properties. Revelant fuel properties of EA/SVO double and D/EA/SVO triple blends have been object of study including kinematic viscosity, pour point (PP), cloud point (CP), calorific value (CV), and cetane number (CN). The suitability of using these blends as fuels has been tested by running them on a diesel engine electric generator, analyzing their effect on engine power output, fuel consumption, and smoke emissions. Results obtained indicate that the D/EA/SO and D/EA/CO triple blends, composed by up to 24% and 36% EA, respectively, allow a fossil diesel substitution up to 60–80% providing power values very similar to conventional diesel.In addition, in exchange of a slight fuel consumption, a very notable lessening in the emission of pollutants as well as a better behavior at low temperatures, as compared to diesel, are achieved. Full article

(This article belongs to the Special Issue Optimization of Biodiesel and Biofuel Process)

► Show Figures

Figure 1

15 pages, 602 KiB

Open AccessArticle

High Vacuum Fractional Distillation (HVFD) Approach for Quality and Performance Improvement of Azadirachta indica Biodiesel

by Bazgha Ijaz, Muhammad Asif Hanif, Umer Rashid, Muhammad Zubair, Zahid Mushtaq, Haq Nawaz, Thomas Shean Yaw Choong and Imededdine Arbi Nehdi

Energies 2020, 13(11), 2858; https://doi.org/10.3390/en13112858 - 3 Jun 2020

Cited by 4 | Viewed by 3954

Abstract

Biodiesel offers an advantage only if it can be used as a direct replacement for ordinary diesel. There are many reasons to promote biodiesel. However, biodiesel cannot get wide acceptance until its drawbacks have been overcome including poor low temperature flow properties, variation in the quality of biodiesel produced from different feedstocks and fuel filter blocking. In the present study, a much cheaper and simpler method called high vacuum fractional distillation (HVFD) has been used as an alternative to produce high-quality refined biodiesel and to improve on the abovementioned drawbacks of biodiesel. The results of the present study showed that none of biodiesel sample produced from crude Azadirachta indica (neem) oil met standard biodiesel cetane number requirements. The high vacuum fractional distillation (HVFD) process improved the cetane number of produced biodiesels which ranged from 44–87.3. Similarly, biodiesel produced from fractionated Azadirachta indica oil has shown lower iodine values (91.2) and much better cloud (−2.6 °C) and pour point (−4.9 °C) than pure Azadirachta indica oil. In conclusion, the crude oil needs to be vacuum fractioned for superior biodiesel production for direct utilization in engine and consistent quality production. Full article

(This article belongs to the Special Issue Optimization of Biodiesel and Biofuel Process)

► Show Figures

Figure 1

16 pages, 1511 KiB

Open AccessArticle

Diethyl Ether as an Oxygenated Additive for Fossil Diesel/Vegetable Oil Blends: Evaluation of Performance and Emission Quality of Triple Blends on a Diesel Engine

by Laura Aguado-Deblas, Jesús Hidalgo-Carrillo, Felipa M. Bautista, Diego Luna, Carlos Luna, Juan Calero, Alejandro Posadillo, Antonio A. Romero and Rafael Estevez

Energies 2020, 13(7), 1542; https://doi.org/10.3390/en13071542 - 25 Mar 2020

Cited by 27 | Viewed by 3572

Abstract

The aim of this work is to analyze the effect of using diethyl ether (DEE) as an oxygenated additive of straight vegetable oils (SVOs) in triple blends with fossil diesel, to be used in current compression ignition (C.I.) engines, in order to implement the current process of replacing fossil fuels with others of a renewable nature. The use of DEE is considered taking into account the favorable properties for blending with SVO and fossil diesel, such as its very low kinematic viscosity, high oxygen content, low autoignition temperature, broad flammability limits (it works as a cold start aid for engines), and very low values of cloud and pour point. Therefore, DEE can be used as a solvent of vegetable oils to reduce the viscosity of the blends and to improve cold flow properties. Besides, DEE is considered renewable, since it can be easily obtained from bioethanol, which is produced from biomass through a dehydration process. The vegetable oils evaluated in the mixtures with DEE were castor oil, which is inedible, and sunflower oil, used as a standard reference for waste cooking oil. In order to meet European petrodiesel standard EN 590, a study of the more relevant rheological properties of biofuels obtained from the DEE/vegetable oil double blends has been performed. The incorporation of fossil diesel to these double blends gives rise to diesel/DEE/vegetable oil triple blends, which exhibited suitable rheological properties to be able to operate in conventional diesel engines. These blends have been tested in a conventional diesel engine, operating as an electricity generator. The efficiency, consumption and smoke emissions in the engine have been measured. The results reveal that a substitution of fossil diesel up to 40% by volume can be achieved, independently of the SVO employed. Moreover, a significant reduction in the emission levels of pollutants and better cold flow properties has been also obtained with all blends tested. Full article

(This article belongs to the Special Issue Optimization of Biodiesel and Biofuel Process)

► Show Figures

Figure 1

19 pages, 3912 KiB

Open AccessArticle

Fe₃O₄-PDA-Lipase as Surface Functionalized Nano Biocatalyst for the Production of Biodiesel Using Waste Cooking Oil as Feedstock: Characterization and Process Optimization

by Tooba Touqeer, Muhammad Waseem Mumtaz, Hamid Mukhtar, Ahmad Irfan, Sadia Akram, Aroosh Shabbir, Umer Rashid, Imededdine Arbi Nehdi and Thomas Shean Yaw Choong

Energies 2020, 13(1), 177; https://doi.org/10.3390/en13010177 - 31 Dec 2019

Cited by 88 | Viewed by 5687

Abstract

Synthesis of surface modified/multi-functional nanoparticles has become a vital research area of material science. In the present work, iron oxide (Fe₃O₄) nanoparticles prepared by solvo-thermal method were functionalized by polydopamine. The catechol groups of polydopamine at the surface of nanoparticles provided the sites for the attachment of Aspergillus terreus AH-F2 lipase through adsorption, Schiff base and Michael addition mechanisms. The strategy was revealed to be facile and efficacious, as lipase immobilized on magnetic nanoparticles grant the edge of ease in recovery with utilizing external magnet and reusability of lipase. Maximum activity of free lipase was estimated to be 18.32 U/mg/min while activity of Fe₃O₄-PDA-Lipase was 17.82 U/mg/min (showing 97.27% residual activity). The lipase immobilized on polydopamine coated iron oxide (Fe₃O₄_PDA_Lipase) revealed better adoptability towards higher levels of temperature/pH comparative to free lipase. The synthesized (Fe₃O₄_PDA_Lipase) catalyst was employed for the preparation of biodiesel from waste cooking oil by enzymatic transesterification. Five factors response surface methodology was adopted for optimizing reaction conditions. The highest yield of biodiesel (92%) was achieved at 10% Fe₃O₄_PDA_Lipase percentage concentration, 6:1 CH₃OH to oil ratio, 37 °C temperature, 0.6% water content and 30 h of reaction time. The Fe₃O₄-PDA-Lipase activity was not very affected after first four cycles and retained 25.79% of its initial activity after seven cycles. The nanoparticles were characterized by FTIR (Fourier transfer infrared) Spectroscopy, XRD (X-ray diffraction) and TEM (transmission electron microscopy), grafting of polydopamine on nanoparticles was confirmed by FTIR and formation of biodiesel was evaluated by FTIR and GC-MS (gas chromatography-mass spectrometry) analysis. Full article

(This article belongs to the Special Issue Optimization of Biodiesel and Biofuel Process)

► Show Figures

Graphical abstract

14 pages, 3743 KiB

Open AccessArticle

Hydrogen Photo-Production from Glycerol Using Nickel-Doped TiO₂ Catalysts: Effect of Catalyst Pre-Treatment

by Jesús Hidalgo-Carrillo, Juan Martín-Gómez, Julia Morales, Juan Carlos Espejo, Francisco José Urbano and Alberto Marinas

Energies 2019, 12(17), 3351; https://doi.org/10.3390/en12173351 - 30 Aug 2019

Cited by 13 | Viewed by 2658

Abstract

In the present piece of research, hydrogen production via the photo-reforming of glycerol (a byproduct from biodiesel generation) is studied. Catalysts consisted of titania modified by Ni (0.5% by weight) obtained through deposition–precipitation or impregnation synthetic methods (labelled as Ni-0.5-DP and Ni-0.5-IMP, respectively). Reactions were performed both under UV and solar irradiation. Activity significantly improved in the presence of Ni, especially under solar irradiation. Moreover, pre-reduced solids exhibited higher catalytic activities than untreated solids, despite the “in-situ” reduction of nickel species and the elimination of surface chlorides under reaction conditions (as evidenced by XPS). It is possible that the catalyst pretreatment at 400 °C under hydrogen resulted in some strong metal–support interactions. In summary, the highest hydrogen production value (ca. 2600 micromole H₂·g⁻¹) was achieved with pre-reduced Ni-0.5-DP solid using UV light for an irradiation time of 6 h. This value represents a 15.7-fold increase as compared to Evonik P25. Full article

(This article belongs to the Special Issue Optimization of Biodiesel and Biofuel Process)

► Show Figures

Graphical abstract

13 pages, 1261 KiB

Open AccessArticle

Performance and Emission Quality Assessment in a Diesel Engine of Straight Castor and Sunflower Vegetable Oils, in Diesel/Gasoline/Oil Triple Blends

by Rafael Estevez, Laura Aguado-Deblas, Alejandro Posadillo, Beatriz Hurtado, Felipa M. Bautista, José M. Hidalgo, Carlos Luna, Juan Calero, Antonio A. Romero and Diego Luna

Energies 2019, 12(11), 2181; https://doi.org/10.3390/en12112181 - 7 Jun 2019

Cited by 14 | Viewed by 3289

Abstract

This research evaluates the possibility of using straight oils such as castor oil, which is not suitable for food use, and sunflower oil, used as a standard reference for waste cooking oils, in blends with gasoline as second-generation biofuels. To this end, a study of the rheological properties of biofuels obtained from these double blends has been carried out. The aim is to take advantage of the different properties of gasoline, i.e., its low viscosity and its high energy density to obtain blends whose rheological properties allow the substitution of fossil diesel in high extent. The incorporation of fossil diesel to these gasoline/oil mixtures produces diesel/gasoline/oil triple blends, which exhibited the suitable rheological properties to be able to operate in conventional diesel engines. Therefore, the behavior of these blends has been evaluated in a conventional diesel engine, operating as an electricity generator. The triple blends allow the substitution of fossil diesel up to 40% with sunflower oil, and up to 25% with castor oil, with excellent power results achieved for blends in which diesel is substituted up to 40%, and also in fuel consumption at high demand in comparison to conventional fossil diesel. Besides, a significant reduction in the emission of pollutants has also been obtained with these triple blends. Full article

(This article belongs to the Special Issue Optimization of Biodiesel and Biofuel Process)

► Show Figures

Figure 1

15 pages, 3575 KiB

Open AccessArticle

Rhizomucor miehei Lipase Supported on Inorganic Solids, as Biocatalyst for the Synthesis of Biofuels: Improving the Experimental Conditions by Response Surface Methodology

by Juan Calero, Diego Luna, Carlos Luna, Felipa M. Bautista, Beatriz Hurtado, Antonio A. Romero, Alejandro Posadillo and Rafael Estevez

Energies 2019, 12(5), 831; https://doi.org/10.3390/en12050831 - 2 Mar 2019

Cited by 9 | Viewed by 3326

Abstract

Two inorganic solids have been evaluated as supports of Lipozyme RM IM, a Rhizomucor miehei lipase immobilized on a macroporous anion exchange resin, in order to improve its application as a biocatalyst in the synthesis of biofuels. The experimental conditions have been optimized to get the selective transesterification of sunflower oil, by using a multi-factorial design based on the response surface methodology (RSM). In this way, the effects of several reaction parameters on the selective ethanolysis of triglycerides to produce Ecodiesel, a biodiesel-like biofuel constitute by one mole of monoglyceride (MG) and two moles of fatty acid ethyl ester (FAEE), have been evaluated. Thus, it was obtained that a 6:1 oil/ethanol molar ratio, 0.215 g of biocatalyst supported in silica-gel (0.015 g Lipase/0.2 g silica-gel), 50 µL of 10 N NaOH, together with previous optimized reaction parameters, 35 °C reaction temperature and 120 min of reaction time, gave the best results (conversions around 70%; selectivity around 65%; kinematic viscosities about 9.3 mm²/s) in the reaction studied. Besides, Lipozyme RM IM, supported on silica-gel, biocatalyst exhibited a very good stability, remaining its activity even after 15 cycles. Full article

(This article belongs to the Special Issue Optimization of Biodiesel and Biofuel Process)

► Show Figures

Figure 1

Review

Jump to: Editorial, Research

20 pages, 1894 KiB

Open AccessReview

An Overview of the Production of Oxygenated Fuel Additives by Glycerol Etherification, Either with Isobutene or tert-Butyl Alcohol, over Heterogeneous Catalysts

by Rafael Estevez, Laura Aguado-Deblas, Diego Luna and Felipa M. Bautista

Energies 2019, 12(12), 2364; https://doi.org/10.3390/en12122364 - 19 Jun 2019

Cited by 24 | Viewed by 5161

Abstract

Biodiesel production has considerably increased in recent decades, generating a surplus of crude glycerol, which is the main drawback for the economy of the process. To overcome this, many scientists have directed their efforts to transform glycerol, which has great potential as a platform molecule, into value-added products. A promising option is the preparation of oxygenate additives for fuel, in particular those obtained by the etherification reaction of glycerol with alcohols or olefins, mainly using heterogeneous catalysis. This review collects up-to-date research findings in the etherification of glycerol, either with isobutene (IB) or tert-Butyl alcohol (TBA), highlighting the best catalytic performances reported. Furthermore, the experimental sets employed for these reactions have been included in the present manuscript. Likewise, the characteristics of the glycerol ethers–(bio)fuel blends as well as their performances (e.g., quality of emissions, technical advantages or disadvantages, etc.) have been also compiled and discussed. Full article

(This article belongs to the Special Issue Optimization of Biodiesel and Biofuel Process)

► Show Figures

Journal Menu

Journal Browser

Optimization of Biodiesel and Biofuel Process

Share This Special Issue

Special Issue Editors

Special Issue Information

Keywords

Benefits of Publishing in a Special Issue

Published Papers (9 papers)

Editorial

Research

Review

Further Information

Guidelines

MDPI Initiatives

Follow MDPI