Hostname: page-component-586b7cd67f-2plfb Total loading time: 0 Render date: 2024-11-27T17:48:49.688Z Has data issue: false hasContentIssue false

Cottonseed oil bleaching by acid-activated montmorillonite

Published online by Cambridge University Press:  09 July 2018

P. Falaras
Affiliation:
Institute of Physical Chemistry, NCSR ‘Demokritos’, 153 10 Aghia Paraskevi Attikis
I. Kovanis
Affiliation:
Institute of Physical Chemistry, NCSR ‘Demokritos’, 153 10 Aghia Paraskevi Attikis
F. Lezou
Affiliation:
Institute of Physical Chemistry, NCSR ‘Demokritos’, 153 10 Aghia Paraskevi Attikis
G. Seiragakis
Affiliation:
MINERVA S.A., Edible oils Enterprises, 31 Valaoritou St., 14452 Metamorphosis, Attica, Greece

Abstract

A progressive decrease in cation exchange capcity (CEC) values was observed by treating Ca-montmorillonite with sulphuric acid solutions and this can be understood in terms of the layered structure of the clay. Elemental analysis showed that moderate activation occurred and only 25–30% of the octahedral cations were removed. At the same time the total surface area and the clay acidity increase. X-ray and FTIR data confirmed that acid activation affects both the octahedral and the tetrahedral sheets. The efficiency of acid-activated montmorillonite for the bleaching of cottonseed oil was investigated. The differences in bleaching efficiency appeared to be due to differences in the physical and chemical properties of the bleaching media. The oil acid value was not affected by the bleaching procedure but a slight shift in the absorption maximum of the bleached cottonseed oil was observed. Medium activation of the clay (treatment of Ca-montmorillonite with 4 N H2SO4) was the most effective in bleaching the cottonseed oil, resulting in the best colour index and the lowest peroxide value. A linear dependence of the bleaching efficiency on the clay surface area and acidity was observed. The role of the increased Bronsted acidity is also discussed.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1999

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Boki, K., Kudo, M., Wada, T. & Tamura, T. (1992) Bleaching of alkali-refined vegetable oils with clay minerals. J. Am. Oil Chem. Soc. 69, 232236.Google Scholar
Bovey, J. & Jones, W. (1995) Characterization of Alpillared acid activated clay catalysts. J. Mater. Chem. 5, 20272035.Google Scholar
Breen, C. (1991) Thermogravimetric study of the desorption of cyclohexylamine and pyridine from an acid-treated Wyoming bentonite. Clay Miner. 26, 473486.CrossRefGoogle Scholar
Breen, C., Deane, A.T. & Flynn, J.J. (1987) The acidity of trivalent cation exchanged montmorillonite. Temperature-programmed desorption and infrared studies of pyridine and «-butylamine. Clay Miner. 11, 169-178.Google Scholar
Breen, C., Madejová, J. & Komadel, P. (1995) Characterization of moderately acid-treated, size fractionated montmorillonites using IR and MASNMR spectroscopy and thermal analysis. J. Mat. Chem. 5, 469474.Google Scholar
Breen, C., Zahoor, E.D., Madejova, J. & Komadel, P. (1997a) Characterization and catalytic activity of acid-treated, size-fractionated smectites. J. Phys. Chem., B. 101, 53245331.CrossRefGoogle Scholar
Breen, C., Watson, R., Madejova, J., Komadel, P. & Klapyta, Z. (1997b) Acid-activated organoclays: preparation, characterization and catalytic activity of acid treated tetraalkylammonium-exchanged smectites. Langmuir, 13, 64736479.CrossRefGoogle Scholar
Brindley, G.W. (1980) Order-disorder in clay mineral structures. Chapter 2 in: Crystal Structures of Clay Minerals and their X-ray Identification (Brindley, G.W. & Brown, G., editors). Mineralogical Society, London.Google Scholar
Bukka, K., Miller, J.D. & Shabtai, J. (1992) FTIR study of deuterated montmorillonites: structural features relevant to pillared clay stabilities. Clays Clay Miner. 40, 92-102.CrossRefGoogle Scholar
Chen, J.P., Hausladen, M.C. & Yang RT. (1995) Delaminated Fe2O3-pillared clay. J. Catal 15 1, 135146.Google Scholar
Edens, G.J., Fitch, A. & Lavy-Feder, A. (1991) Use of isopotential points to elucidate ion exchanged reaction mechanisms. J. Electroanal. Chem. 307, 139-154.CrossRefGoogle Scholar
Falaras, P. (1998) Synergetic effect of carboxylic acid functional groups and fractal surface characteristics for efficient dye sensitization of titanium oxide. Solar Energy Mat. Solar Cells, 53, 163175.Google Scholar
Falaras, P. & Lezou, F. (1998) Electrochemical behavior of acid activated modified electrodes. J. Electroanal. Chem. 455, 169179.CrossRefGoogle Scholar
Gregg, S.J. & Sing, K.S.W. (1982) Adsorption, Surface Area and Porosity, 2nd edition, Academic Press, London.Google Scholar
Griffiths, J. (1990) Acid activated bleaching clays. Industrial Minerals, 55-67.Google Scholar
Hymore, F.K. (1996) Effects of some additives on the performance of acid activated clays in the bleaching of palm oil. Appl. Clay Sci. 10, 379385.CrossRefGoogle Scholar
Kellens, M. (1997) Current Developments in Oil Refining Technology. LIPIDEX 1997, (Kellens, M., editor). De Smet Group, Antwerp, Belgium.Google Scholar
Komadel, P., Schmidt, D., Madejova, J. & Čičel, B. (1990) Alteration of smectites by treatments with hydrochloric acid and sodium carbonate solutions. Appl. Clay Sci., 5, 113122 Google Scholar
Kumar, P., Jasra RV. & Bhat, T.S.G. (1995) Evaluation of porosity and surface acidity in montmorillonite clay on acid activation. Ind. Eng Chem. Res. 34, 14401448.Google Scholar
Laszlo, P. (1987) Chemical reactions on clays. Science, 235, 1473-1477.Google Scholar
Mielke, T. (1991) Oil Word Annual, (Mielke, T., editor). ISTA Mielke, Hamburg.Google Scholar
Moenke, H.H.W. (1974) Silica, the three dimensional silicates, borosilicates and berylium silicates. Pp. 365-382 in: Infrared Spectra of Minerals. (Farmer, V.C., editor). Mineralogical Society, London.Google Scholar
Mokaya, R. & Jones, W. (1994) Pillared acid-activated particles. J. Chem. Soc, Chem. Commun. 929-930.Google Scholar
Mokaya, R. & Jones, W. (1995) Pillared clays and pillared acid-activated clays: A comparative study of physical, acidic, and catalytic properties. J. Catal. 153, 7685.Google Scholar
Mokaya, R., Jones, W. & Davis, M. (1993) Chlorophyll adsorption by alumina pillared acid-activated clays. J. Am. Oil Chem. Soc. 70, 241247.Google Scholar
Molinard, A., Peeters, K.K., Maes, N., & Vansant, E.F. (1994) Restoring the cation exchange capacity of alumina pillared montmorillonite through modification with ammonium. In: Separation Technology, Proc. Third Int. Symp. on Separation Technology (Vansant, E.F., editor). Elsevier Science, Amsterdam.Google Scholar
Morgan, D.A., Shaw, D.B., Sidebottom, M.J., Soon, T.C. & Taylor, R.S. (1985) The function of bleaching earths in the processing of palm, palm kernel and coconut oils. J. Am. Oil Chem. Soc. 62, 292299.Google Scholar
Mortland, M.M. & Raman, K.V. (1968) Surface acidity of smectites in relation to hydration, exchangeable cation, and structure. Clay Miner. 16, 393398.CrossRefGoogle Scholar
Osthaus, B.B. (1956) Kinetic studies of montmorillonite and nontronite by the acid dissolution technique. Clay Miner. 4, 301321.CrossRefGoogle Scholar
Padley, F.B., Gunstone, F.D. & Harwood, J.L. (1996) Occurrence and characteristics of oils and fats. Pp. 47 in: The Lipid Handbook (Gunstone, F.D., editor). Chapman & Hall, London.Google Scholar
Pritchard, J.L.R (1994) Analysis of Oilseeds, Fats and Fatty Foods. (Rossell, D., editor) Elsevier, Amsterdam.Google Scholar
Sing, K.S.W., Everett, D.H., Haul, R.A.W., Moscou, L., Pierotti, R.A., Rouquerol, J. & Siemieniewska, T. (1985) Reporting physisorption data for gas/solid systems. Pure Appl. Chem. 57, 603-619.Google Scholar
Taylor, D.R., Ungermann, C.B. & Demidowicz, Z. (1984) The adsorption of fatty acids from vegetable oils with zeolites and bleaching clay/zeolite blends. J. Am. Oil Chem. Soc. 61, 13721379.CrossRefGoogle Scholar
Theocharis, C.R (1993) The measurement of mesoporosity in multifunctional mesoporous inorganic solids. Pp. 3-18 in. Multifunctional Mesoporous Inorganic Solids (Sequeira, C. & Hudson, M., editors). Proc. NATO ASI Series C, 400.Google Scholar
Tkač, I., Komadel, P. & Muller, D. (1994) Acid-treated montmorillonites — A study by 29Si and 27A1 MAS NM. Clay Miner. 29, 1119.Google Scholar
Van Olphen, H. & Fripiat, J.J. (1979) Data Handbook for Clay Materials and Other Non-Metallic Minerals. Pergamon Press.Google Scholar
Vicente Rodriguez, M.A., Lopez Gonzalez, J.D. & Bañares Muñoz, M.A. (1994) Acid activation of Spanish sepiolite: physicochemical characterization, free silica content and surface area of products obtained. Clay Miner. 29, 361367.Google Scholar
Vicente Rodriguez, M.A., Lopez Gonzalez, J.D. & Bañares Muñoz, M.A. (1995) Preparation of microporous solids by acid treatment of a saponite. Micropor. Mat. 4, 251264.CrossRefGoogle Scholar
Vicente Rodriguez, M.A., Suarez, M., Lopez Gonzalez, J.D. & Bañares Muñoz, M.A. (1996) Characterization, surface area and porosity analyses of the solids obtained by acid leaching of a saponite. Langmuir, 12, 566572.Google Scholar