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The potential for a sustainable biodiesel production by modified biobased catalyst : a review

- Bitire, S. O., Jen, T. C., Belaid, M.

Production of Biodiesel from Moringa Oleifera and Jatropha Curcas Seed Oils over a Modified ZnO/Fly Ash Catalyst

- Bombo, Katlego, Lekgoba, Tumeletso, Azeez, Oluwatosin, Muzenda, Edison

Optimization and characterization of biofuel from waste cooking oil

- Emeji, Ikenna C., Afolabi, Ayo S., Jalama, Kalala & Abdulkareem, Ambali S.

  • Authors: Emeji, Ikenna C., Afolabi, Ayo S., Jalama, Kalala & Abdulkareem, Ambali S.
  • Date: 2016
  • Subjects: Biodiesel , Waste cooking oil , Co-solvent , Transesterification
  • Language: English
  • Type: Conference proceedings
  • Identifier: http://hdl.handle.net/10210/91821 , uj:20150 , Citation: Emeji, Ikenna C. et al. 2016. Optimization and characterization of biofuel from waste cooking oil.
  • Description: Abstract: Waste cooking oil (WCO) is regarded as one of the cheapest feedstock for the production of biodiesel. The waste cooking oil used in this study was prepared in the laboratory by adding 5 wt. % of oleic acid into 95 wt. % of soybeans oil. 10 wt. % of titania-supported-magnesium oxide catalyst (MgO/TiO2) used was prepared by incipient wetness impregnation and characterized using XRF and XRD. These materials were tested and used as catalyst for the conversion of waste vegetable oil to biodiesel in the presence of methanol and hexane as co-solvents. Methanol to hexane mole ratio of 1:1 was employed in the transesterification process. The effects of reaction time, reaction temperature and hexane co-solvent on the waste vegetable oil conversion have been established. The 1HNMR analysis was used to estimate the waste vegetable oil conversion and the average molecular formula of fatty acid methyl esters (FAME) produced. It was observed that the oil conversion increased with the increase in reaction time, reaction temperature and use of hexane as co-solvent.
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Biodiesel synthesis using clinoptilolite-Fe3O4-based phosphomolybdic acid as a novel magnetic green catalyst from salvia mirzayanii oil via electrolysis method : optimization study by Taguchi method

- Helmi, Maryam, Ghadiri, Mahdi, Tahvildari, Kambiz, Hemmati, Alireza

Effective diffusivity in solid catalysts for the conversion of waste vegetable Oils into biodiesel : part 1-effect of light hydrocarbons as Co-solvent

- Kalala, Jalama

Energy requirement estimates for two step ethanolysis of waste vegetable oils for biodiesel production

- Ligeris, Nikolas, Jalama, Kalala

  • Authors: Ligeris, Nikolas , Jalama, Kalala
  • Date: 2014
  • Subjects: Waste vegetable oils , Biodiesel , Ethanol
  • Type: Article
  • Identifier: uj:5052 , http://hdl.handle.net/10210/13591
  • Description: ChemCad 6.4 simulation package was used to model a two-step biodiesel production process from waste vegetable oils (WVO) and ethanol using homogeneous acid and alkali catalysts respectively. The developed process flowsheet consisted of pre-esterification and transesterification of WVO, ethanol and glycerol recovery, and biodiesel refining. The energy required for each processing unit as well as the energy required for the whole process have been estimated. Ethanol recovery accounted for the highest portion of the energy required for the entire process estimated as 2.75 MJ per kg of biodiesel produced.
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Characterizing sunflower oil biodiesel blends as alternatives to fossil diesel

- Madyira, Daniel M., Nkomo, Zanele, Akinlabi, Esther Titilayo

  • Authors: Madyira, Daniel M. , Nkomo, Zanele , Akinlabi, Esther Titilayo
  • Date: 2012
  • Subjects: Fossil diesel , Sunflower oil , Biodiesel
  • Type: Article
  • Identifier: uj:4666 , ISBN 978-988-19252-2-0 , http://hdl.handle.net/10210/10046
  • Description: This paper reports on investigation into the feasibility of using sunflower oil based biodiesel blends as alternatives to fossil diesel fuel. The current global reliance on fossil fuels is coming to an end. This is driven on one hand by the dwindling global fossil fuel reserves and the understanding of the consequences of carbon accumulation in the atmosphere on the other. Dwindling reserves continue to drive global fuel prices upwards with negative effects on economic performance. Continued accumulation of carbon dioxide in the atmosphere is perceived to be responsible for the Greenhouse Gas (GHG) effect. This dual problem can be addressed by using alternative renewable fuel sources, which guarantee continued supply while maintaining global carbon neutrality. Biofuels are now largely recognized as viable options. Some of the challenges of using biodiesel in conventional diesel engines are their low density, which leads to low calorific value and acidity levels that threatens the structural integrity of the engine. Blending biodiesel with petroleum diesel can mitigate these effects and lead to better performing fuels. Fuel characterization is therefore essential to establishing notable similarities and differences between biodiesel and fossil diesel, and in determining optimum blending proportions for more effective use of biodiesels. In this investigation, biodiesel was produced from commercial sunflower cooking oil using the batch trans-esterification process with methanol in the presence of Sodium hydroxide catalyst. The characterization of the biodiesel was then conducted using Nuclear Magnetic Resonance (NMR), bomb calorimetry, acidity and flash point analysis, sulphur content tests and Gas Chromatography (GC). Blends ranging between 5% and 50% biodiesel concentration in Ultra-Low Sulphur Diesel (ULSD), in increments of 5% were analyzed. Results obtained confirmed that biodiesel has lower calorific value than ULSD, implying higher fuel consumption. The high flash point, almost at a temperature twice as high as that of ULSD, though advantageous for storage and transportation, results in poor ignition. The results also suggest that an increase in concentration of biodiesel leads to larger difference in properties between the blend and the ULSD. The pH value of biodiesel was found to be lower than that of ULSD which compromises engine structural integrity. Biodiesel’s chain length was found to contain an average of 19 carbons which makes it a viable option when compared to ULSD. Despite the relatively inferior properties measured, biodiesel still remains one of the most attractive fuel options.
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Biodiesel production over ZnO/TiO₂ catalyst : effect of co-solvent, temperature and reaction time

- Mahangani, Ndanganeni, Vunain, Ephraim, Meijboom, Reinout, Jalama, Kalala

  • Authors: Mahangani, Ndanganeni , Vunain, Ephraim , Meijboom, Reinout , Jalama, Kalala
  • Date: 2015-07-01
  • Subjects: Biodiesel , Hexane , Waste vegetable oils
  • Type: Article
  • Identifier: uj:5127 , ISBN 9789881404701 , http://hdl.handle.net/10210/14090
  • Description: The aim of this work was to produce biodiesel from waste vegetable oil over ZnO/TiO2 catalysts as well as investigating the effect of co-solvent (hexane), reaction temperature and time on waste vegetable oil conversion to biodiesel. Production of biodiesel from virgin oil is still a downfall in commercial processes due to high cost. Thus, the process of producing biodiesel from waste vegetable oil over a TiO2-supported ZnO catalyst was studied in the absence and the presence of hexane as co-solvent respectively. The conversion of waste vegetable oil was found to increase with temperature and reaction time. The highest conversion that has been achieved was 99.1% at a temperature of 200 °C after 15 min of reaction for the reaction using hexane as co-solvent. The use of hexane as co-solvent was found to increase the oil conversion at lower reaction temperature and no effect was observed at higher temperatures.
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Estimating the absorption of volatile organic compounds in four biodiesels using the Unifac procedure

- Mateescu, Corina M., Muzenda, Edison, Belaid, Mohamed, Abdulkareem, Saka, Afolabi, Ayo S.

  • Authors: Mateescu, Corina M. , Muzenda, Edison , Belaid, Mohamed , Abdulkareem, Saka , Afolabi, Ayo S.
  • Date: 2011
  • Subjects: Biodiesel , Volatile organic compounds , Absorption
  • Type: Article
  • Identifier: http://ujcontent.uj.ac.za8080/10210/363185 , uj:4696 , http://hdl.handle.net/10210/10760
  • Description: This work considered the thermodynamic feasibility of scrubbing volatile organic compounds into biodiesel in view of designing a gas treatment process with this absorbent. A detailed vapour – liquid equilibrium investigation was performed using the original UNIFAC group contribution method. The four biodiesels studied in this work are methyl oleate, methyl palmitate, methyl linolenate and ethyl stearate. The original UNIFAC procedure was used to estimate the infinite dilution activity coefficients of 13 selected volatile organic compounds in the biodiesels. The calculations were done at the VOC mole fraction of 9.213x10-8. Ethyl stearate gave the most favourable phase equilibrium. A close agreement was found between the infinite dilution activity coefficient of toluene found in this work and those reported in literature. Thermodynamic models can efficiently be used to calculate vast amount of phase equilibrium behaviour using limited number of experimental data.
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Biodiesel production over nano-MgO supported on titania

- Mguni, Liberty L, Meijboom, Reinout, Jalama, Kalala

Biodiesel production from soybean oil over TiO2 supported nano-ZnO

- Mukenga, Mbala, Muzenda, Edison, Jalama, Kalala, Meijboom, Reinout

Phase equilibrium of volatile organic compounds in polymeric solvents using group contribution methods

- Muzenda, Edison

  • Authors: Muzenda, Edison
  • Date: 2010
  • Subjects: Volatile organic compounds , Phase equilibrium , Glycol polymers , Biodiesel
  • Type: Article
  • Identifier: uj:4697 , http://hdl.handle.net/10210/10930
  • Description: Group contribution methods such as the UNIFAC are of major interest to researchers and engineers involved synthesis, feasibility studies, design and optimization of separation processes as well as other applications of industrial use. Reliable knowledge of the phase equilibrium behavior is crucial for the prediction of the fate of the chemical in the environment and other applications. The objective of this study was to predict the solubility of selected volatile organic compounds (VOCs) in glycol polymers and biodiesel. Measurements can be expensive and time consuming, hence the need for thermodynamic models. The results obtained in this study for the infinite dilution activity coefficients compare very well those published in literature obtained through measurements. It is suggested that in preliminary design or feasibility studies of absorption systems for the abatement of volatile organic compounds, prediction procedures should be implemented while accurate fluid phase equilibrium data should be obtained from experiment.
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Volatile organic compounds- biodiesel thermodynamic interactions: influence of temperature

- Ramdharee, Sashay, Muzenda, Edison, Belaid, Mohamed

Influence of structure on fatty acid ester-alkane interactions

- Scheepers, Jacques J., Muzenda, Edison, Belaid, Mohamed

  • Authors: Scheepers, Jacques J. , Muzenda, Edison , Belaid, Mohamed
  • Date: 2012
  • Subjects: Absorption , Activity coefficients , Biodiesel , Esters , Volatile organic compounds
  • Type: Article
  • Identifier: uj:4671 , ISSN 978-988-19252-2-0 , http://hdl.handle.net/10210/10436
  • Description: The activity coefficients of alkane structures in various types of fatty acid ester solvents was measured in order to determine the effect of bond interactions between these two chemical species. It is important to understand the mechanics of these interactions for absorber system design. Activity coefficients were determined by use of a Microsoft Excel spreadsheet designed for this purpose. It was determined that the length of the ester chain, as well as ester chain saturation had an impact on activity coefficients, in that saturated ester chains and longer ester chains yielded lower activity coefficients. Multiple branched cycloalkanes yielded lower activity coefficients than straight chain hydrocarbons and unbranched cycloalkanes. It was also noted that the location of the carboxyl group in the ester chain had no influence on activity coefficients.
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Challenges hindering development of small scale of biodiesel production in South Africa

- Thaba, Sebonkile Cynthia, Mbohwa, Charles

Waste vegetable oils to biodiesel over Al₂O₃ –supported SnO₂ catalyst : effect of support pore size

- Zulu, Vusumuzi C., Vunain, Ephraim, Meijboom, Reinout, Jalama, Kalala

  • Authors: Zulu, Vusumuzi C. , Vunain, Ephraim , Meijboom, Reinout , Jalama, Kalala
  • Date: 2015-07-01
  • Subjects: Biodiesel , Waste vegetable oils
  • Type: Article
  • Identifier: uj:5132 , ISBN 9789881404701 , http://hdl.handle.net/10210/14098
  • Description: The main aim of this study was to investigate the catalytic properties of Al₂O₃-supported SnO₂ for the conversion of waste vegetable oil into biodiesel. The effect of support pore size on waste oil conversion was investigated at 100 and 200 °C by using α-alumina (with larger pore size) and γ-alumina (with smaller pore size) respectively as support for SnO₂. The effect of pore-size on conversion was found to depend on the operating temperature. At low temperature, i.e. 100 °C, higher conversion for waste vegetable oil was measured on SnO₂ catalyst supported on α-Al₂O₃ than the catalyst supported by γ-Al₂O₃. This effect became less significant at 200 °C. It was also observed that the oil conversion increased with an increase in reaction temperature and reaction time.
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