The most important findings of the research will follow in this section. In addition to achievements with significance to progress in science of biodiesel processing some technical and technological conclusions will also be presented in the form of recommendations to practice.
Feedstocks of biodiesel processing can be as different as many production variables can pertain. Based on the findings that the most valuable asset of any FAME production consists in the feedstock special attention must be paid to selection of the kind of the seed and to strictly adhering to recommended technology conditions. Production of biodiesel at small and medium scale units are at best incorporated into an (agro)-industrial ecological system.
Algae feedstocks do not seem to be explored in the near future, mainly because of cost and properties. The most beneficial feature of algae oil can be explored in the field of healthy food, because of high content in polyunsaturated fatty acids and phosphorous.
THESES:
1. BY THE USE OF SUITABLE APOLAR SOLVENT PHASE TRANSFER RESISTANCE AGAINST TRANS-ESTERIFICATION CAN BE AVOIDED
I have demonstrated through liquid-liquid equilibrium tests that there is a beneficial range of addition of apolar solvent to form a single liquid phase by reaction partners. By such removal of the interfacial resistance the rate of trans-esterification reaction could have been significantly improved. The outcome of avoiding phase transfer resistance complete conversion was achieved in 5 minutes, in comparison to 30-60 minutes times on stream for reaching the equilibrium conversion if the solvent was not present.
2. BY THE USE OF SUITABLE APOLAR SOLVENT PHASE TRANSFER RESISTANCE AGAINST METHANOLYSIS CAN BE INSTITUTED. BLOCKING THE CURSE OF REVERSIBLE REACTION THE FORWARD TRANS-ESTERIFICATION CAN BE SHIFTED TOWARD A COMPLETE CONVERSION:
I have found, that the byproduct can be instantaneously rejected from the reaction mixture to shift the conversion toward completion in a single contact event without including an intermittent operation for separation of the byproduct (and another if the solvent is polar). The proposed techniques were demonstrated both in batch and continuous counter current setups.
The mechanism is based on the engineered condition by the addition of the selected apolar solvent to reinstall an interfacial barrier against the return of the byproduct into the reaction phase. The reinstalled interfacial resistance efficiently bars the reverse glycerolysis reaction of FAME.
3. I IMPROVED THE RATE AND SELECTIVITY OF SEPARATION OF MAIN AND BYPRODUCTS BY THE USE OF A SUITABLE APOLAR SOLVENT:
It was pointed out in my work that if the suitable apolar solvent was added at proper rate the rejection of the glycerol has been almost instantaneous and complete. This finding made possible to execute the reaction contact and the phase separation in a single contact device.
This contact device is preferably a counter current reactor-extractor. For existing systems modification of reactors to a loop reactor configuration can be a practice for performing the same operations.
In addition to faster splitting of the fuel and glycerol phases the selectivity of this operation can be significantly increased to reduce the loss of product into the polar byproduct. The amount main product in the G phase could have been reduced to 0.5-1%.
4. I DEMONSTRATED THAT ESTERIFICATION AND TRANS-ESTERIFICATION PROVIDES IMPETUS TO SOLVENT REFINING OF THE PRODUCTS
I demonstrated by addition of glycerol that it forms a polar extractant to selectively extract gum and phosphorous components into the polar phase. Because of kinetic characteristics this can be accomplished in counter current mode of operation too. I have also demonstrated that these improvements in selectivity and kinetics of separation are controlled by colloid chemical characteristics of the system.
Because of the selective refining action of the newly formed polar phase pre-treatment of the feedstock must not be as strict as the requirement for first generation biodiesel plants to remove gum components.
5. I DISCOVERED THAT STERIFICATION OF FREE FATTY ACID FOLLOWS AN INTERFACIAL REACTION PATTERN
The mechanism of esterification must be of mixed type: partly in homogeneous phase and partly at the interface, I would call this course of reaction interfacial type. The kinetic rate measurements indicate this intermediary position, faster than in conventional systems, but much slower than in homogeneous systems. The rate limiting is being dependent on interface renewal. By the use of ion exchange resin the reaction is interfacial similar to heterogeneous catalytic chemistry.
6. I FOUND OUT THAT THE G-PHASE IS A DISPERSION OF THE TYPE OF MULTIPLE,
SOLID PARTICLES STABILIZED EMULSION OF PICKERING TYPE
I demonstrated that the more complex the colloid structure of the feedstock was the more difficult and more severe treatment conditions had to be employed. For refining the byproduct G-phase a model has been proposed that the G-phase is a multiple, solid particles stabilized emulsion structure (so called Pickering type emulsion) that encapsulates solid and oil components.
DEVELOPMENTS WITH RELEVANCE TO INDUSTRIAL REALIZATIONS: BY THE USE OF APOLAR SOLVENT
• THE OVERALL SPECIFIC ENERGY DEMAND CAN BE REDUCED,
• PROCESSING FOOTPRINT OF A UNIT CAN BE REDUCED,
• OBSOLETE PLANTS CAN BE MODERNIZED
I have been looking for a technique to reduce the overall specific energy demand of biodiesel processing. The most important contribution to reduction of specific energy demand is associated with less energy consumed for intensive mixing. It has been proved that the specific energy demand of maintaining the disperse state for the promotion of contact of reaction mixture components surpasses the energy needed for pumping. I calculated that the additional amount of energy needed for solvent and reagent recycle is significantly lower (by 20-40%) than the specific energy consumption in cases of reference.
• TECHNOLOGY DEVELOPED
These findings made possible to develop two variants of the apolar solvent assisted biodiesel processing.
A truly continuous operation realized with counter current reaction extraction and distillation columns as the main contact devices. The truly continuous operation makes possible to profit of heat exchangers for rational energy management. Footprint of the operational units and amount of inventory under operational conditions can be reduced accordingly. These features make the system more environmentally respectful, more safe than those mixer-settler based technologies in which the time on stream to product is more than 3 times longer than in the proposed system.
I have recommended a system for retrofit of conventional unites to more efficient, more ecological systems. This can be done switching from mixer-settler operation to loop reactor system by the use of suitable apolar solvent.
Future works are planned in the pilot plant of the truly continuous biodiesel processing and in industrial scale demonstration of retrofitting.
Future works are ongoing to explore other type of feedstocks that are high in essential fatty acids, such as algae and fish oil.
PAPERS RELATED TO THE SUBJECT OF THE THESIS IN JOURNALS:
INTERNATIONAL PEER REVIEWED JOURNALS, CONTRIBUTIONS DIRECTLY RELATED TO THE SUBJECT
1. KOVÁCS A.: The potential to boost capacity and efficiency in small to medium sized biodiesel production systems, Journal of Industrial Ecology, Volume 16, Issue 1, pages 153–162, February 2012 (IF: 2.446)
2. KOVÁCS A.: Aspects of refining biodiesel byproduct glycerin, Petroleum & Coal 53 (1) 91-‐97, 2011, (IF: 0.5),
3. KOVÁCS A., Czinkota I, Tóth J.: Improving Acid Number Testing of Biodiesel Feedstock and Product, Journal of the American Oil Chemists' Society, 2012, Volume 89, Number 3, Pages 409-‐417 (IF:
1.587, részesedés: 75%),
4. KOVÁCS A., Ball C.: Use of colloid chemistry to improve to improve biodiesel production, Periodica Polytechnica, Chemical Engineering, 56/1, 37-‐48, 2012 (IF: 0.2),
INTERNATIONAL PEER REVIEWED JOURNALS, CONTRIBUTIONS PARTIALLY RELATED TO THE SUBKECT
5. Szele E., Gombos K., KOVÁCS A., Ember I.: Feeding Purified Glycerol from Biodiesel to CBA/CA Mice: Effects on Gadd45a and Nfkb1 Expressions. In Vivo 2010, 24 (3): 303-‐308 (IF: 1.143 részesedés:
25%)
6. Szele E., Gombos K., KOVÁCS A., Ember I: Effects of Purified Glycerol from Biodiesel on Cyp1a1 and Cyp2e1 Expressions in CBA/CA Mice. In Vivo 2011, 25 (2): 237-‐240 (IF: 1.143 részesedés: 25%) 7. Szendi K., Gerencsér G., KOVÁCS A., Varga Cs.: Biodízel előállításakor képződött glicerin fázis melléktermék vizsgálata in vivo genotoxikológiai tesztekben. Magyar Epidemiológia 2011; 8(1):21-‐26.
8. Kovács P., Zsédey E., KOVÁCS A., Virág, Gy.,Schmidt J.: Apparent digestible and metabolizable energy content of glycerol in feed of growing pigs, Livestock Science, Volume 142, Issue 1 , Pages 229-‐
234, December 2011 (impact factor:1.295 részesedés: 20%)
PRESENTATIONS IN INTERNATIONAL CONFERENCES:
9. KOVÁCS A., Haas, L, Majoros, I: Research and application examples for clean technologies, Intl.
Conf. on 21ST Century Environmental Technologies, June 13 and 14, Budapest, 2002
10. KOVÁCS A., Haas: Biodiesel technology, a step closer to hydrocarbon processing practice, Interfaces02, Budapest, Szept. 19-‐20, 2002
11. KOVÁCS A., Haas: Affordable biodiesel technology, Bioenergy, Proc. P. 172, 2002, Sept. 22-‐26, 2002, Boise, Idaho
12. KOVÁCS A.:Efficient and affordable biodiesel technology with reserves to improve operational technologies, 4th European Motor BioFuels Forum, 24 -‐ 26 Nov., 2003 Berlin
13. KOVÁCS A.: Industrial ecology in environmnetal project conception building and implementation, Industrial Ecology Conference of Visegrád Countries, June 2004, Budapest
14. KOVÁCS A.: Biodiesel perspectives in production and use, Interfaces’05, Sopron, Sept 15-‐17, 2005
15. KOVÁCS A.: Industrial Ecology Interfaces’05, Sopron, Sept 15-‐17
16. KOVÁCS A., Haas L.: Chemical Engineering Means of Improving Efficiency in Biodiesel KOVÁCS A., Czinkota: An essay on environmental and rural development in production and use of alternative fuels from the viewpoint of a chemical engineer, Celje, Slovenia, invited lecture, 2007
17. KOVÁCS A.: Feedstock and operational aspects of ecologically engineered biodiesel technologies, WIREC2008, Washington, 2007
18. KOVÁCS A., Haas L: Chemical Engineering Means of Improving Efficiency in Biodiesel Production Technologies, Eastern Biofuels Conference and Expo, II, Budapest, 2006, May-June
19. KOVÁCS A.: Are renewable energy based fuel also sustainable? Interfaces08, Sopron, 2008 20. KOVÁCS A., Czinkota I, Nagy L, Issa I, Tolner L: Use of biodiesel byproduct in agriculture. 6th ISMOM, International Symposium of Interactions of Soil Minerals with Organic Components and Microorganisms , 26th June-‐1st July 2011, Montpellier, France
21. KOVÁCS A.: Manipulation of colloid chemistry improves the efficiency and profitability of biodiesel production, poster presentation, International Biomass conference and expo, , 16-‐20, April 2012, Denver, Co., USA
22. KOVÁCS A., Ball, C.: Modification of colloid chemistry to improve biodiesel production, European Biodiesel 2012, 13-‐14 June in Krakow, Poland
23. KOVÁCS A., Ball, C.: Exploring the Science of Colloid Chemistry to Improve Profitability of Biodiesel Processing Operations, BIT’s 2nd Low Carbon Earth summit, NEF-2012, Guangzhou, Oct. 17-21, 2012
ARTICLES IN DOMESTIC PERIODICALS
24. KOVÁCS A.: Alternatív üzemanyagok, Hatékony Energia, 4. 2-‐3, 27-‐28, 1999KOVÁCS A.:
Megújuló alternatív üzemanyagok, Energia Központ, Phare, EU FP5 kiadvány
25. KOVÁCS A., Haas, L: Jobbított biodízelel technológia kőolajipari tudományos alapokon Magyar Kémikusok Lapja, 59.6-‐7, 220-‐225, 2004
26. KOVÁCS A. Industrial Ecology, how do I approach on the basis of energy related disciplines, Industrial Ecology in favor of business and environment, 2. Dec., 2003, Budapest
27. KOVÁCS A., Haas, L: Jobbított biodízel technológia kőolajipari tapasztaatok alapján, Olaj Szappan, Kozmetika, vol 54., No, 1, 2005
28. KOVÁCS A., Haas, L: Biodízel gyártásának, felhasználásának műszaki, gazdaságossági kérdései, Olaj Szappan, Kozmetika, vol 54., No, 2, 2005
29. KOVÁCS A.: Agro-‐industrial-‐ecology approach to renewable energy resources, BioEnergia, vol2.No.5,7-‐10, 2007
30. Szele E., Gombos K, Juhász K, Wohler V, KOVÁCS A, Ember I: Biodízel előállításra felhasznált kukoricaolaj és sárgazsír karcinogenézisben betültött szerepének állatkísérletes vizsgálata különböző mRNS-ek és miRNS-ek kifejeződésének mérésével (Effect of corn oil and yellow grease on mRNAs and miRNAs which play central role in carcinogenesis in animal research, Magyar Epidemiológia, IX. 3., 173-182, 2012
31. Szele E, Gombos K, Juhász K, KOVÁCS A, Ember I: Biodízel gyártás során visszamaradt szappanos vízzel kezelt talajon termesztett búza metabolizmusra és karcinogenézisre gyakorolt hatásának vizsgálata állatkísérletes modellben (Effect of wheat raised on soil fertilized with soap water, the by-product of biodiesel, on carcinogenesis and metabolism in animal research), Magyar Epidemiológia, IX. 3., 183-192, 2012
32. Gerencsér G, Szendi K, KOVÁCS A, Ember I: Biodízel gyártása során keletkező melléktermékkel kezelt talajok ökotoxikológiai vizsgálata (Ecotoxicity testing of soil treated with byproducts of biodiesel processing), Magyar Epidemiológia, IX. 3., 209-214, 2012
33. Szendi K, Gerencsér G, KOVÁCS A, Ember I: Talajjavító és szelektív növényvédszer komponensek genotoxikológiai és ökotoxikológiai vizsgálata (Genotoxocity and ecotoxicity studies on soils treated with structural and selective pesticide components), Magyar Epidemiológia, IX. 3., 215-224, 2012
PRESENTATIONS IN DOMESTIC CONFERENCES
34. KOVÁCS A., Haas L: Új Biodízel technológia, MKE, VEN, Veszprém, p 352-‐356, 2002
35. KOVÁCS A., Haas, L: Az energiastratégia regionális kérdéseinek biodízelre vonatkozó szempontjai, Energia Fórum Debrecen, 2004, Szept. 17
36. KOVÁCS A.: Megfizethető és hatékony technológia és üzemi körülmények a biodízel gyártásáben, Debrecen, Energexpo and Conference, 2006
37. Tolner, L Zőldi M., KOVÁCS A., Kertész: Biodízelgyártás melléktermékeként keletkező glicerin hatása a talaj ásványi nitrogéntartalmára. Zöldenergia, földhő és napenergia hasznosítása a
hőtermelésben Konferencia, Gyöngyös, 2010.05.20. Konferenciakiadvány 110-‐114. ISBN:
978-‐963-‐9941-‐12-‐0
38. KOVÁCS A., Czinkota I, Tolner L: Agroökológiai alapú megújuló́ energiatermelési rendszer.
Zöldenergia, földhő és napenergia hasznosítása a hőtermelésben Konferencia, Gyöngyös, 2010.05.20.
113-‐114, ISBN: 978-‐963-‐9941-‐12-‐0
39. KOVÁCS A., Tolner L, Czinkota I, Tóth J: Biodízel technológia hulladék alapanyagokból.
Zöldenergia, földhő és napenergia hasznosítása a hőtermelésben Konferencia, Gyöngyös, 2010.05.20.
Konferenciakiadvány 106-‐112. ISBN: 978-‐963-‐9941-‐12-‐0
40. Tolner L, KOVÁCS A., Kovács A, Vágó I, Czinkota I: Ellentmondások a biodízelgyártás melléktermék mezőgazdasági hasznosíthatóságában. Zöldenergia, földhő és napenergia hasznosítása a hőtermelésben Konferencia, Gyöngyös, 2010.05.20. Konferenciakiadvány 154-‐158. ISBN:
978-‐963-‐9941-‐12-‐0
41. KOVÁCS A., , Czinkota I, Kovács A, Tolner L: Biodízel melléktermék alkalmazása a talajvédelemben. Erdei Ferenc VI. Tudományos Konferencia, 2011. augusztus 25., Kecskemét
PATENTS
42. KOVÁCS A. et others: P014786, Jobbított biodízelel technológia növényi olaj átészterezésével, 2001
43. KOVÁCS A. et others.: PCT/HU02/00114 Improvement in or rellating to a method for transesterifying vegetable oils, 2002
44. KOVÁCS A., Sinoros Szabó: Alternatív szilárd tüzelőanyag (Alternative solid fuel), 2009 45. KOVÁCS A. Transesterification of vegetable oils, 2009 UK 5633001: PCT/GB2009/000246, WO/2009/095668
BOOK
46. KOVÁCS A: Biodízel technológia 2003, KUKK K+F, ISBN963 00 9789 3, Budapest,
L
ITERATURE CITED[1] Rao, K. V. C.: Production of hydrocarbons by thermolysis of vegetable oils US Patent 4102938, 1978
[2] Wright et al: Oil & Soap 1944, 145., 26. Freedman et al: J. Am. Oil Chem. Soc. 1986, 63, 1375.
[3] Jon Van Gerpen: Biodiesel processing and production, Fuel Processing Technology 86, 1097–
1107, 2005
[4] Consortium: Agroök07 project, Hungarian National Board for Technology under the call of Jedlik07 scheme, 2010
[5] DIRECTIVE 2009/28/EC OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL of 23 April 2009 on the promotion of the use of energy from renewable sources and amending and subsequently repealing Directives 2001/77/EC and 2003/30/EC
[6] Vidal, J: Sweden Plans to Be World's First Oil-‐Free Economy. 15-‐year limit set for switch to renewable energy. Biofuels favoured over further nuclear power, The Guardian, 02.8, 2006, Energy in Sweden 2010, ET2010_47w.pdf (Size: 2.41 MB, Pages: 144)
[7] A joint study by EUCAR / JRC / CONCAWE: Well-‐to-‐Wheels analysis of future automotive fuels and power trains in the European context, 2007
Armstrong et al: Energy and greenhouse gas balance of biofuels for Europe -‐ an update, report no 2/02, 2002
[8] Kovács A. -‐ Czinkota I. -‐ Nagy A. -‐ Issa I. -‐ Tolner L. (2011): Use of biodiesel byproduct in agriculture. 6th ISMOM, International Symposium of Interactions of Soil Minerals with Organic Components and Microorganisms , 26th June-‐1st July 2011, Montpellier, France
[9] Prankl, Wörgette.: Influence of the Iodine Number of Biodiesel to the Engine Performance.
Proceedings of the 'International Conference on, Standardization and Analysis of Biodiesel', 6-‐7 Nov 1995, Vienna. ISBN 3 9014, 5701 1.
[10] Mittelbach, M. and Remschmidt, C. Biodiesel, the Comprehensive Handbook; Ed.: M.Mittelbach, 2006, Graz. ISBN: 3-‐200-‐00249-‐2
[11] Sanford et al: Feedstock and Biodiesel Characteristics Report, Renewable Energy Group®, Nov.
2009
[12] Razon, L.F.: Alternative crops for biodiesel feedstock, CAB Reviews: Perspectives in agriculture, veterinary science, nutrition and natural resources, vol. 4, 56, 2009
[13] Körbitz et al. 2004: Best Case Studies on Biodiesel Production Plants in Europe, report prepared for IEA Bioenergy Task 39 by the Austrian Biofuel Institute
[14] Kocsisova, Teodora, Cvengros, Jan (2006): G-‐phase from methy ester production – splitting and refining, Petroleum and Coal 48. (2) 1-‐5
[15] Taylor, Phil, 2008, Synthetic glycerine is back, but never really went away,
http://www.inpharmatechnologist.com/ Materials-‐Formulation/Synthetic-‐glycerine-‐is-‐back-‐
but-‐never-‐really-‐went-‐away-‐!.
[16] Eisentraut, A.: Sustainable Production of Second -‐Generation Biofuels. Potential and perspectives in major economies and developing countries, Information paper, International Energy Agency, February, 2010
[17] Frosch, R. and N. Gallopoulos: Strategies for manufacturing. Scientific American Vol. 261 No.3 144–1521989
[18] COMMISSION DECISION of 10 June 2010 on guidelines for the calculation of land carbon stocks for the purpose of Annex V to Directive 2009/28/EC (notified under document C(2010) 3751) (2010/335/EU), Official Journal of the European Union L 151/19, 17.6.2010
[19] Collier, P. and C.P. Alles: Materials Ecology: An Industrial Perspective, Science, Vol. 330 no. 6006 pp. 919-‐920, 2010
[20] Martin, M.: Industrial Symbiosis in Biofuel Industries: A case for improved environmental and economical performance in http://www.iei.liu.se/envtech/omoss/michael_martin /1.122334/
Industrial SymbiosiswithBiofuels.pdf, 2009
[21] Chertow, M.R.: “Uncovering” Industrial Symbiosis, Journal of Industrial Ecology, Vol 11, No. 1. 11-
30., 2007
[22] Radich, A. 2004: Biodiesel Performance, Costs, and Use, http://www.eia.doe.gov/oiaf/
analysispaper/biodiesel/, last modified on Tue Jun 08 2004
[23] Bacovsky, D. et al.: Biodiesel Production: Technologies and European Providers. IEA Task 39 Report T39-‐B6, 104 pp. 2007
[24] Freedman, Pryde, Mounts: Variables affecting the yields of fatty esters from transesterified vegetable oils, JAOCS 61. 1638– 1643. 1984
[25] Noureddini, H. and D. Zhu.: Kinetics of transesterification of soybean oil, Journal of the American Oil Chemists Society, 74, 11, 1457-‐1463. 1997
[26] Körbitz, W: Multi-‐feedstock-‐biodiesel: The modern and profitable FAME production plant, Int.
Liquid Biofuels Congress, Brasil, 1998
[27] Multi-‐Client Study: Biodiesel 2020: A Global Market Survey, 2nd Edition, http://www.emerging-‐
markets.com/PDF/Biodiesel2020Study.pdf, 2008
[28] Garti at al: Polyglycerol esters: optimization and techno-‐economic evaluation, JAOCS, 58, 9, 878-‐
883, 1981
[29] Stein, Glaser: Continuous solvent extraction of sunflower, seed, groundnuts, palm kernels, rapeseed, and copra, JAOCS, 53., 6. 283-‐285, 1976
[30] Pathak, et al: Performance of oil milling technologies in India. Agricultural Mechanism in Asia, Africa and Latin America, 19. 4, 68-‐72. 1988.
[31] Kovács A.: Biodízel technológia, KUKK K+F Kft, Budapest, ISBN: 9630097893, 2003
[32] Dufaure et. al: A twin-‐screw extruder for oil extraction, direct expression of oleic sunflower seeds, JAOCS, 76, 1073-‐1077, 1999
[33] Johnson, Lusas: Comparison of alternative solvents for oil extraction, JAOCS 60. 2 181-194, 1983 [34] Gardarelli, Grapiste: Hexane sorption in oil seed meals, JAOCS 73. 12 1657-‐1661, 1996
[35] Penninger et al. (ed.): Supecritical fluid technology, Process Technology Proceedings, Vol. 3.
Elsevier, 1985
[36] Stahl et al: Extraction of seed oils with liquid and supercritical carbon dioxide, J. Agric. Food Chem., Vol. 28 (6), 1153–1157, 1980
[37] Simándi et al: Szuperkritikus oldószerek alkalmazása a lignocellulózok hasznosításában, Olaj, Szappan, Kozmetika, Vol. 50, 115-‐118, 2001
[38] Speight, J, G: The chemistry and technology of petroleum, 4th ed., CRC Press, 2007 [39] Brunner, G.: Mass transfer in gas extraction, in Penninger et al. (ed.): Supecritical fluid
technology, Process Technology Proceedings, Vol. 3. P. 245-‐261, Elsevier, 1985
[40] Reverchon, E.: Supercritical fluid extraction and fractionation of essential oils and related products. The Journal of Supercritical Fluids, Vol.10, 1, 1-‐37. 1997.
[41] Gillis, Van Tine: What’s new in solvent deasphalting? UOP & FOSTER WHEELER team up in solvent deasphalting, http://www.fwc.com/publications/tech_papers/oil_gas/Uop_fw~2.pdf [42] Le Page et al: Resid and heavy oil processing, Editions Technip, 1992
[43] Wenclawiak, B (Ed): Analysis with suoercritical fluids: extraction and chromatography, Apringer Verlag, 1992
[44] Riera et al: Mass transfer enhancement in supercritical fluids extraction by means of power ultrasound, Ultrasonics Sonochemistry Vol. 11 p. 241–244, 2004
[45] Haas, M: Production of value added lipids, biofuels, and biobased products from fats and oils, Project No.: 1935-‐41000-‐066-‐00, 2004-‐2009
[46] Haas et al: Production of fatty acid alkyl esters, US Patent 7,612,221, 2009
[47] Kovács, A: Alternatív üzemanyag gyártástechnológiai jobbítása, új alkalmazási lehetőségek vizsgálata, GVOP 3.1.1-‐2004-‐04-‐0004/3.0, 2004-‐2005
[48] Zeng et al: Rapid in situ transesterification of sunflower oil, Industrial and Engineering Chemistry research, Vol.48.,2, 850-‐856, 2009
[49] Petty, H. R. Molecular Biology of Membranes: Structure and Function; Plenum: New York, 1993 [50] Yawata ,Y (ed.): Cell Membrane, Wiley-‐VCH Verlag GmbH & Co. KGaA, 2003 (on/line: 2004) [51] Hübschner et al: The analysis of tissue phospholipids, procedure and results : hydrolysis with
pig liver, Vol1., No.5, 433-‐438, 1960
[52] Zufarov et al: Degumming of rapeseed and sunflower oils, Acta Chimica Slovaca, vol.1 No.1 321-‐
328, 2008
[53] Said et al: Process for degumming a fatty substance and fatty substance thus obtained, US Patent 6015915, 2000
[54] Bohsle, Subramanian: New approaches in deacidification of edible oils, J. Food. Eng, vol. 69, 481-‐
494, 2005
[55] Coutinho et al: State of art of the application of membrane technology to vegetable oils: A review, Food Research International 42 536–550, 2009
[56] Ochoa, et al: Ultrafiltration of vegetable oils. Degumming by polymeric membranes. Separation and Purification Technology, 417–422, 2001
[57] Chow and Ho: Surface active properties of palm oil with respect to the processing of palm oil, Journal of Oil Palm Research Vol. 12 No. 1, June 2000, p. 107.116
[58] Xianglong Yuan: Evaluation on antioxidant activities of soybean oils and gums, M.S. Thesis, M.S., Louisiana State University, 2006
[59] Frega et al: Effects of free fatty acids on oxidative stability of vegetable oil, Journal of the American Oil Chemists' Society, vol 76, No 3, 325-‐329, 1999
[60] Romanić et al: Oxidative stability and tocopherol content of refined sunflower oil during long-‐
term storage in different commercial packagings, Acta Alimentaria, vol. 38, No. 3, 319-‐327, 2009 [61] Eychenne and Moulounguv: Deacidification of a synthetic oil with an anion exchange resin,
JAOCS, 75, 10, 1437-‐1440, 1998
[62] Kovács et al: Polyol ester oils for industrial purposes, 6-‐th Intl. Coll, Esslingen, Germany 1988 [63] Soest et al: Polyol refining, Patent application number: 20090030243, 2009
[64] Kalichevsky, Kobe: Petroleum refining with chemicals, Elsevier Pub. Co., 1956
[65] List et al: Supercritical CO2 degumming and physical refining of soybean oil, JAOCS, 70, 5, 473-‐
467, 1993
[66] Bohsle, Subramanian: New approaches in deacidification of edible oils, J. Food. Eng, vol. 69, 481-‐
494, 2005
[67] Waintraub et al: Conversion of a deasphalting unit for use in the process of supercritical solvent recovery, Braz. J. Chem. Eng. 17, 3, 355-‐360, 2000
[68] Speight, J.G.: The Chemistry and Technology of Petroleum, Fourth Edition CD & W Inc., Laramie, Wyoming, USA, ISBN: 9780849390678 , 2006
[69] Rodriges et al: Deacidification of vegetable oils by solvent extraction, Recent patents on engineering, 1, 95-‐102, 2007
[70] Bollmann, H: Process of producing an article of food, US Patent No. 1606052, 1926 [71] van Dijk: Process for refining fatty compounds, US Patent 2268786, 1942
[72] Bertholet, R: Process for refining fatty substances, US Patent 6506916, 2003
[73] Turck, : R.: Method for producing fatty acid esters of monovalent alkyl alcohols and use thereof, US Patent 6,538,146
[74] Kovács, Haas: Affordable biodiesel technology, Bioenergy, Proc. P. 172, 2002, Sept. 22-‐26, 2002, Boise, Idaho
[75] Anderson, A.: Refining of oils and fats for edible purposes, 2.ed., 92-‐103, Pergamon Press, London, 1962
[76] Going, L.H.: Interesterification products and processes, JAOCS, 44, 9 414-‐422, 1967
Cosmacini, Vertuani: New developments in the field of sznthetic lubricants from natural sources, Journal of synthetic lubrications, 5,1, 1-‐12, 2006
[77] Lee et al: reducing the crystallization temperature of biodiesel by winterizating methyl soyate, JAOCS, 73.5 631-‐640, 1996
[78] Lee et al: Reducing the crystallization temperature of biodiesel by winteriying mthyl soyate, JAOCS, vol.73, 5, 631-‐636, 1996
[79] De Greyt et al: Recent Developments in Bleaching, Deodorisation and Physical Refining of Oils and Fats, OFI Middle East 2008, Technical and Commercial Conference Hilton Hotel Abu Dhabi, UAE, April 15-‐16,2008
[80] Munson et al: Biodiesel purification by a continuous regenerable adsorbent process, US Patent 20090199460, http://www.freepatentsonline.com/y2009/0199460.html
[81] Marcetti et al: Heterogeneous esterification of oil with high amount of FFA, Fuels, 86, 906-‐910.
2007
[82] Goto et al: Kinetics f the transesterification of palmitic acid with isobutyl alcohol, International Journal of Chemical Kinetics, vol. 23, 1, 17-‐26, 1991
[83] Santacesaria et al: Kinetics and Mass Transfer of Free Fatty Acids Esterification with Methanol in a Tubular Packed Bed Reactor: A Key Pretreatment in Biodiesel Production, Ind. Eng. Chem. Res., 46 (15), pp 5113–5121, 2007
[84] Chen et al: Computational studies of the countercurrent multistage extraction coupled esterification of oleic acid with methanol using excess methanol as extractant, Chemical Engineering research and Design, vol 82. 5, 599-‐604, 2004.
[85] Pasias et al: Heterogeneously Catalyzed Esterification of FFAs in Vegetable Oils, Chemical Engineering & Technology, Vol 29, 11, 1365–1371, 2006
[86] Berrios et al: Study of esterification and transesterification in biodiesel production from used frying oils in a closed system, Chemical Engineering Journal, 160, 473-‐479, 2010