Integrated process for potassium sulfate and a mixture Of ammonium chloride/potassium sulfate salts production

Authors

  • Yousef Mubarak The University of Jordan

DOI:

https://doi.org/10.14419/ijet.v7i1.9188

Published:

2018-02-25

Keywords:

Ammonium Chloride, Ammonium Sulfate, Crystallization, Potassium Sulfate, Potassium Chloride.

Abstract

Relatively pure and coarse crystalline potassium sulfate of about 52 wt % K2O content and almost chlorine free has been obtained by reacting commercial potassium chloride and commercial ammonium sulfate in a stirred tank reactor at moderately low temperature. To increase the yield of potassium sulfate to a reasonable value, an evaporation stage located between the reactor and the crystallizer is used. The main steps of the production process include dissolution, reaction, evaporation, crystallization, centrifuging, drying, and then cooling. It is found that the best operating parameters to produce potassium sulfate of good quality, quantity, and crystal size are 1:1 as KCl/ (NH4)2SO4 mole ratio, 60 ºC reaction temperature, 1 hour reaction time, about one third of the total water used in the dissolution step is to be evaporated, 10 ºC crystallization temperature, 1 hour crystallization time, and 160 and 60 rpm agitation speeds in the reactor and the crystallizer respectively. Applying these operating conditions, a potassium sulfate yield of about 78 % can be achieved. Also, a fully soluble complex salt as a mixture of ammonium chloride and potassium sulfate is obtained by further treatment of the mother liquor. Further concentration of the mother liquor by further water evaporation of about 40 wt % and then crystallization of the slurry at 25 oC can recover up to about 60 wt % of the remaining solid in the mother liquor as a complex salt. The total yield of potassium sulfate is found to be about 95 wt % and the whole value of the solid product obtained is about 79 wt %.

References

[1] V.S. Meena, B.R. Maurya, J.P. Verma, R.S. Meena, Potassium Solubilizing Microorganisms for Sustainable Agriculture, Springer India, 2016. https://doi.org/10.1007/978-81-322-2776-2.

[2] U.S. Jones, Fertilizers and Soil Fertility, 2nd ed., New Delhi, 1987.

[3] K. Reid, D. Aspinall, Soil Fertility Handbook, Ontario Legislative Library, 2006.

[4] Potassium Sulfate, The Great Soviet Encyclopedia, 3rd Edition (1970-1979), The Gale Group Inc., 2010, https://encyclopedia2.thefreedictionary.com/Potassium+Sulfate.

[5] A.K. Kolay, Manures and Fertilizers, Atlantic publishers and Distributors, 2007.

[6] R.M. McKercher, Potash Technology: Mining, Processing, Maintenance, Transportation, Occupational Health and Safety, Environment, Pergamon Press, 1983.

[7] R.N. Shreeve, Chemical Process Industries: Mannheim Process, 3rd ed., McGraw-Hill, 1967.

[8] V. Gowariker, S. Gowariker, V.N. Krishnamurthy, M. Ghanorkar, K. Paranjape, the Fertilizer Encyclopedia, John Wiley and Sons, 2009.

[9] F.T. Nielsson, Manual of Fertilizer Processing, Marcel Dekker Inc., 1987.

[10] D.E. Garrett, Sodium Sulfate: Handbook of Deposits, Processing, Properties, and Use, Academic Press, 2001.

[11] C. Holdengraber, S. Lampert, Process for Producing Potassium Sulfate from Potash and Sodium Sulfate, patent, US 6143271, 2000.

[12] F.R. George, Recovery of potassium sulphate from polyhalite, patent, US1812497 A, 1931.

[13] T.H. Neuman, R.W. Chastain, D.M. Felton, D.C. Neuman, O.C. Schanuber, Methods Of Processing Polyhalite Ore, Methods of Producing Potassium Sulfate, and Related Systems, patent, US 8551429 B2, 2013.

[14] B. Gunn, Production of potassium sulphate from naturally occurring sodium sulphate and potassium chloride, The Canadian Journal of Chemical Engineering 42(4) (1964) 187-190. https://doi.org/10.1002/cjce.5450420412.

[15] X. Wang, X. Han, X. Zhang, Q. Li, and T. Xu, Modeling of Potassium Sulfate Production from Potassium Chloride by Electrodialytic Ion Substitution, ACS Sustainable Chem. Eng. 5(10) (2017) 9076–9085. https://doi.org/10.1021/acssuschemeng.7b01992.

[16] R. Phinney, Method of producing potassium sulfate, patent, US6315976 B1, 2001.

[17] Potassium chloride specifications. http://www.arabpotash.com/Pages/viewpage.aspx?pageID=30. Accessed December 26, 2017.

[18] L. Wang, Q. Xia*, J. Kang, M.X. Du, G.L. Zhang, and F.B. Zhang, Measurement and Correlation of Solubilities of Potassium Chloride and Potassium Sulfate in Aqueous Glycerol Solutions, Journal of Chemical Engineering Data 56(10) (2011) 3813–3817. https://doi.org/10.1021/je200238s.

[19] S. Sawamura, N. Yoshimoto,Y. Taniguchi, Y. Yamaura, Effects of pressure and temperature on the solubility of ammonium chloride in water, Journal of High Pressure Research 16(4) (1999) 253-263. https://doi.org/10.1080/08957959908200298.

[20] A.G. Jones, J.W. Mullin, Programmed Cooling Crystallization of Potassium Sulphate Solution, Chemical Engineering Science 29 (1974) 105-118. https://doi.org/10.1016/0009-2509(74)85036-0.

[21] A.S. Myerson, R. Ginde, Handbook of Industrial Crystallization: Crystal Growth and Nucleation, Butterworth-Heinemann, 1993, pp. 33-63.

[22] F. Schuth, Nucleation and Crystallization of Solids from Solutions, Curr Opin Solid State Mater Sci. 5 (2001) 389-395. https://doi.org/10.1016/S1359-0286(01)00023-7.

[23] J. Utomo, Experimental Kinetics Studies and Wavelet-Based Modeling of a Reactive Crystallization System, Thesis (Ph.D.), Curtin University, Australia, 2009.

[24] N. Kubota, N. Doki, M. Yokota, D. Jagadesh, Seeding effect on product crystal size in batch crystallization, Journal of Chemical Engineering Japan 35(11) (2002) 1063-1071. https://doi.org/10.1252/jcej.35.1063.

[25] S. Zainal Abidin, G.K.F. Ling, L.C. Abdullah, S. Ahmad, R. Yunus, T. Choong, Effects of Temperature and Cooling Modes on Yield, Purity and Particle Size Distribution of Dihydroxystearic Acid Crystals, European Journal of Scientific Research 33(3) (2009) 471-479.

[26] J.B. Sardisco, Production of potassium sulfate and hydrogen chloride, patent, US4045543, 1977.

[27] J.W. Mullin, Crystallization, 4th ed., Boston, MA, Butterworth-Heinemann, 2001.

[28] J.W. Mullin, C. Gaska, Potassium sulfate crystal growth rates in aqueous solution, J. Chem. Eng. Data 18(2) (1973) 217-220. https://doi.org/10.1021/je60057a030.

View Full Article: