Optimal Consume of NaOH in Starches Gelatinization for Froth Flotation
Starches are widely used as depressant in froth flotation operations in Brazil due to their efficiency, increasing the selectivity in the inverse flotation of quartz depressing iron ore. Starches market have been growing and improving in recent years, leading to better products attending the requirements of the mineral industry. The major source of starch used for iron ore is corn starch, which needs to be gelatinized with sodium hydroxide (NaOH) prior to use. This stage has a direct impact on industrials costs, once the lowest consumption of NaOH in gelatinization provides better control of the pH in the froth flotation and reduces the amount of electrolytes present in the pulp. In order to evaluate the gelatinization degree of different starches and flour were subjected to the addiction of NaOH and temperature variation experiments. Samples of starch (corn, cassava, HIPIX 100, HIPIX 101 and HIPIX 102 commercialized by Ingredion) and flour (cassava and potato) were tested. The starch samples were characterized through Scanning Electronic Microscopy and the amylose content were determined through spectrometry, swelling and solubility tests. The gelatinization was carried out through titration with NaOH, keeping the solution temperature constant at 40 oC. At the end of the tests, the optimal amount of NaOH consumed to gelatinize the starch or flour from different botanical sources was established and a correlation between the content of amylopectin in the starch and the starch/NaOH ratio needed for its gelatinization.
Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1127204Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1043
 J. B. Clemmer, “Flotation of Iron Ore,” Duluth, Minnesota, USA, 8th Annual Mining Symposium, 1947.
 A. C. Araújo, P. R. M. Viana, and A. E. C. Peres, “Reagents in iron ores flotation,” Minerals Engineering, vol. 18, pp. 219–224, 2005.
 A. E. C. Peres, and M. I. Corrêa, “Depression of iron oxides with corn starches,” Minerals Engineering, vol. 9, n. 12, pp. 1227–1234, 1996.
 H. D. G. Turrer, and A. E. C. Peres, “Investigation on alternative depressants for iron ore flotation,” Minerals Engineering, vol. 23, pp. 1066–1069, 2010.
 C. L. L. Pinto, A. C. Araújo, and A. E. C. Peres, “The effect of starch, amylose and amylopectin on the depression of oxi–minerals,” Minerals Engineering, vol. 5, n. 3–5, pp. 469–478, 1992.
 Q. Liu, Y. Zhang, and J. S. Laskowski, “The adsorption of polysaccharides onto mineral surfaces: an acid/base interaction,” International Journal of Mineral Processing, vol. 60, pp. 229–245, 2000.
 S. S. Ibrahim, and N. A. Abdel–Khalek, “The action of different types of corn starch on the flocculation of phosphate slimes,” Minerals Engineering, vol. 5, n. 8, pp. 907–916, 1992.
 P. K. Weissenborn, “Behaviour of amylopectin and amylose components of starch in the selective flocculation of ultrafine iron ore,” International Journal of Mineral Processing, vol. 47, pp. 197–211, 1996.
 B. Kar, H. Sahoo, S. S. Rath, and B. Das, “Investigations on different starches as depressants for iron ore flotation,” Minerals Engineering, vol. 49, pp. 1–6, August 2013.
 M. Wootton, and P. Ho, “Alkali gelatinisation of wheat starch,” Starch, vol. 41, pp. 261–265, 1989.
 M. Tang, and Q. Liu, “The acidity of caustic digested starch and its role in starch adsorption on mineral surfaces,” International Journal of Mineral Processing, vol. 112–113, pp. 94–100, August 2012.
 F. K. Broome, C. W. Hoerr, and H. J. Harwood, “The binary systems of water with dodecylammonium chloride and its N-methylderivated,” J. Am. Chem. Soc., vol. 73, pp. 3350–3352, 1951.
 I. Iwasaki, and R. W. Lai, “Starches and starch products as depressants in soap flotation of activated silica from iron ores,” Trans. Am. Inst. Min. Metall. Pet. Eng., vol. 232, pp. 364–371, 1965.
 L. S. Leal Filho, S. M. Assis, A. C. Araújo, and A. P. Chaves, “Process mineralogy studies for optimizing the flotation performance of two refractory phosphate ores,” Minerals Engineering, vol. 6, n. 8–10, pp. 907–916, July 1993.
 L. O. Fillipov, V. V. Severov, and I. V. Fillippova, “Mechanism of starch adsorption on Fe–Mg–Al–bearing amphiboles,” International Journal of Mineral Processing, vol. 123, pp. 120–128, 2013.
 I. Iwasaki, W. J. Carlson, and S. M. Parmeter, “The use of starches and starch derivatives as depressants and flocculants in iron ore beneficiation,” Trans. ASME – AIME, vol. 224, pp. 88–98, 1969.
 R. C. Guimarães, A. C. Araújo, and A. E. C. Peres, “Reagents in igneous phosphate ores flotation,” Minerals Engineering, vol. 18, pp. 199–204, 2005.
 S. R. B. Cooke, N. F. Schultz, and E. W. Lindroos, “The effect of certain starches on quartz and hematite suspensions,” Trans. AIME, vol. 193, pp. 697–698, 1952.
 N. S. Mikhailova, “Research of interaction of starch with some oxices and silicates,” Obogashenie rud, vol. 6, pp. 20–23, 1972.
 P. R. G. Brandão, L. G. Caires, and D. S. B. Queiroz, “Vegetable lipid oil based collectors in the flotation of apatite ores,” Minerals Engineering, vol. 7, n. 7, pp. 917–925, 1994.
 L. O. Fillipov, V. V. Severov, and I. V. Fillippova, “An overview of the beneficiation of iron ores via inverse cationic flotation,” International Journal of Mineral Processing, vol. 127, pp. 62–69, 2014.
 N. Singh, J. Singh, L. Kaur, N. S. Sodhi, and B. S. Gill, “Morphological, thermal and rheological properties of starches from different botanical sources,” Food Chemistry, vol.81, n. 2, pp. 219–231, May 2003.
 C. C. Denardin, and L. P. Silva, “Estrutura dos grânulos de amido e sua relação com propriedades físico–químicas,” Revista ciência rural, vol. 39, n. 3, pp. 945–954, 2009.