Research ArticleOpen AccessGoogle Scholar indexed
Continuous Melt Suspension Crystallization of Phosphoric Acid
Chemical Engineering Research Center, East China University of Science and Technology, Shanghai, PR China
Chemical Engineering Research Center, East China University of Science and Technology, Shanghai, PR China
Chemical Engineering Research Center, East China University of Science and Technology, Shanghai, PR China
Chemical Engineering Research Center, East China University of Science and Technology, Shanghai, PR China
Chemical Engineering Research Center, East China University of Science and Technology, Shanghai, PR China
- 1 Chemical Engineering Research Center, East China University of Science and Technology, Shanghai, PR China
- 2 Chemical Engineering Research Center, East China University of Science and Technology, Shanghai, PR China
- 3 Chemical Engineering Research Center, East China University of Science and Technology, Shanghai, PR China
- 4 Chemical Engineering Research Center, East China University of Science and Technology, Shanghai, PR China
- 5 Chemical Engineering Research Center, East China University of Science and Technology, Shanghai, PR China
Journal of Crystallization Process and Technology·Volume 02 (2012)·Pages 111–116·Published 26 July 2012·DOI10.4236/jcpt.2012.23014
Copy link · social · email
Abstract
A continuous melt suspension crystallization process has been presented for the purification of the phosphoric acid in this study, which is performed in the cascade of a mixed suspension mixed product removal (MSMPR) crystallizer and a gravity wash column for the subsequent solid-liquid separation. Dynamic behavior in the crystallizer and role of reflux ration on the purification efficiency of column are studied in detail. A reasonable steady state with respect to the liquid phase is achieved after 2 to 3 hrs, which is followed by a solid-phase steady state in terms of the slurry density after 4 hrs. Reflux ratio is the effective parameter for separation and purification by the crystallization equipment from the influences of reflux ratio on the purity of product, the number of theoretical plates and the stability of the operations.
KeywordsPhosphoric AcidSuspension CrystallizationMsmpr CrystallizerReflux Ratio
- P. Becker, “Phosphates and Phosphoric Acid,” Marcel Decker Inc., New York, 1983.
- M. Feki, “Contribution to the phosphoric-acid purification of wet process by extraction with the methyl-isobutylcetone,” Ph.D. Thesis, University of Sciences, Tunis, 2001.
- R. Dhouib-Sahnoun, M. Feki and H.F. Ayedi, “Extractive purification of wet phosphoric acid with tributyl-phosphate: study of the impurities distribution,” J. de la Sciété de Tunisie, Vol. 8, 2000, pp. 873-885.
- A.M. Urtiaga, A. Alonso, I. Ortiz, J.A. Daoud and S.A. El-Reefy, “Comparison of liquid membrane processes for the removal of cadmium from wet phosphoric acid,” J. Membr. Sci., Vol. 164, No. 1, 2000, pp. 229-240.
- V. Kislik and A. Eyal, “Aqueous hybrid liquid membrane process for metal separation. Part II. Selectivity of metals separation from wet-process phosphoric acid,” J. Membr. Sci., Vol. 169, No. 1, 2000, pp. 133-146.
- J.F. McCullough, “Phosphoric acid purification: comparing the process choices,” Chem. Eng., Vol. 83, 1976, pp. 101-106.
- W.J. Huang, “Progress in the field of purifying wet-process phosphoric acid by solvent precipitation,” Chem. Eng. Prog., Vol. 6, 1997, pp. 39-43.
- Jian Zhu, “Preparation of electric-grade phosphoric acid by melt crystallization,” CN Patent No. 1843900, 2006.
- Hongyuan Wei and Leping Dang, “Purification of phosphoric acid by crystallization,” CN Patent No. 1730385, 2006.
- Kim Chul Ung and Koh Jae Cheon, “Purification method of phosphoric acid through layer crystallization including washing operation,” KR Patent No. 20060111282(A), 2006.
- Aaltonen, Jarmo and Sakari, “Process for production of phosphoric acid by crystallization of phosphoric acid hemihydrates,” WO Patent No. 00/59827, 2000.
- Yamazaki Yasuo, Tabei Seikichi and Negishi Kat-suyuki, “High purity phosphoric acid,” JP Patent No. 2000026111, 2000.
- Tadeusz K., Wiewiorowski, Phillip D. Mollere, Vivian C. Astley and David M.Dyer, “Phosphoric acid crystallization process,” US Patent No. 4655789, 1987.
- Hara Hisao, Yoshikawa Akihisa and Kubo Masao, “Production of highly purified phosphoric acid,” JP Patent No. 2225309, 1990.
- M. Matsuoka, T. Fukuda, Y. Takagi and H. Takiyama, “Purification of Organic Solid Solutions by Melt Crystallization: Comparison between Layer and Suspension Crystallization,” J. Cryst. Growth, Vol. 166, No. 1, 1996, pp. 1035-1039.