Colza oil bleaching through optimized acid activation of bentonite. A comparative study

Abstract The acid activation of an Algerian bentonite was investigated using a factorial 3 3 experiment design in order to improve the bleaching capacity in the colza oil processing. Optimized acid treatment of this bentonite gave rise to an effective bleaching earth in colza oil treatment. The 80 °C temperature value was regarded as being convenient in this study. For this purpose, the effects at 80 °C of three key parameters were investigated, namely the effects of the acid concentration in aqueous solution, the contact time and the clay to acid (S/L) ratio upon the clay effectiveness, regarded as the response function to be prone to modeling, simulation and optimization. The results showed that the acid concentration displays a stronger individual effect, as compared to the other parameters. In optimal activation conditions (acid concentration 31%, contact time 10 h and solid to liquid ratio 320 g/L), the highest bleaching capacity was found to be 99%. Comparison of the bleaching capacity from our bentonite shows that similar performances require less acid activated bentonite than any other bentonite. The acid acid-activated bentonite displayed also even higher color and chlorophyll removal than both the Tonsil and Maghnia standards, for similar bleaching earth amounts. The recommended features for the colza oil were obtained using only 1 wt.% of acid-activated bentonite, as compared to the Tonsil and Maghnia standard (1.2–1.4 and 2 wt.%, respectively). The model adequacy was also verified through additional bleaching experiment within the fixed parameters ranges, and was discussed.

[1]  C. Alamprese,et al.  The role of bleaching clays and synthetic silica in palm oil physical refining , 2003 .

[2]  D. Taylor,et al.  Bleaching with alternative layered minerals: A comparison with acid-activated montmorillonite for bleaching soybean oil , 1989 .

[3]  Enoch Y. Park,et al.  Potential application of waste activated bleaching earth on the production of fatty acid alkyl esters using Candida cylindracea lipase in organic solvent system , 2004 .

[4]  Influence of the Chemical Composition and Textural Characteristics of Palygorskite on the Acid Leaching of Octahedral Cations , 1987 .

[5]  E. Park,et al.  Kinetic study of esterification of rapeseed oil contained in waste activated bleaching earth using Candida rugosa lipase in organic solvent system , 2005 .

[6]  M. Ouali,et al.  Decoloration d'une huile alimentaire avec une bentonite activee par irradiation micro-onde , 2002 .

[7]  A. Azzouz,et al.  Optimized procedure for clay pillaring with aluminum species used in depollution , 2006 .

[8]  Masayasu Sato,et al.  Repeated production of fatty acid methyl ester with activated bleaching earth in solvent-free system , 2006 .

[9]  M. Bayramoğlu,et al.  Statistical modeling and optimization of ultrasound-assisted sulfuric acid leaching of TiO2 from red mud , 2004 .

[10]  G. Christidis,et al.  Compositional Variations in Smectites: Part I. Alteration of Intermediate Volcanic Rocks. A Case Study from Milos Island, Greece , 1993, Clay Minerals.

[11]  M. Bagane,et al.  Prparation d'une argile active pour la dcoloration de l'huile d'olive , 1999 .

[12]  L. B. Sukla,et al.  Aqueous SO2 leaching studies on Nishikhal manganese ore through factorial experiment , 2000 .

[13]  T. Pinnavaia,et al.  Acid Hydrolysis of Octahedral Mg2+ Sites in 2:1 Layered Silicates: An Assessment of Edge Attack and Gallery Access Mechanisms , 1994 .

[14]  J. D. Caldwell,et al.  The determination of active filter aid adsorption sites by temperature-programmed desorption , 1994 .

[15]  I. Tkáč,et al.  Acid-Treated Montmorillonites—A Study by 29Si and 27Al MAS NMR , 1994, Clay Minerals.

[16]  M. Önal,et al.  The Effect of Acid Activation on Some Physicochemical Properties of a Bentonite , 2002 .

[17]  Y. Sarikaya,et al.  Investigation of the Surface Acidity of a Bentonite Modified by Acid Activation and Thermal Treatment , 2003 .

[18]  A. Salem,et al.  Kinetic model for the isothermal activation of bentonite by sulfuric acid , 2008 .

[19]  Erdal Cokca.  Relationship between Methylene Blue Value, Initial Soil Suction and Swell Percent of Expansive Soils , 2002 .

[20]  E. Srasra,et al.  Textural properties of acid activated glauconite , 2000 .

[21]  F. K. Hymore.  Effects of some additives on the performance of acid-activated clays in the bleaching of palm oil , 1996 .

[22]  Oral Laçin,et al.  Statistical modelling of acid activation on cotton oil bleaching by Turkish bentonite , 2006 .

[23]  A. Bensmaili,et al.  Removal of Ga(III) from aqueous solution by adsorption on activated bentonite using a factorial design. , 2002, Water research.

[24]  Robert Hausler,et al.  Optimized extraction of total proteic mass from water hyacinth dry leaves , 2004 .

[25]  P. W. Scott,et al.  Acid activation and bleaching capacity of bentonites from the islands of Milos and Chios, Aegean, Greece , 1997 .