Investigation of Dissolution in Diammonium Hydrogen Phosphate Solutions of Gypsum

Gypsum (CaSO4.2H2O) is a mineral that is found in
large quantities in the Turkey and in the World. In this study, the
dissolution of this mineral in the diammonium hydrogen phosphate
solutions has been studied. The dissolution and dissolution kinetics of
gypsum in diammonium hydrogen phosphate solutions will be useful
for evaluating of solid wastes containing gypsum. Parameters such as
diammonium hydrogen phosphate concentration, temperature and
stirring speed affecting on the dissolution rate of the gypsum in
diammonium hydrogen phosphate solutions were investigated. In
experimental studies have researched effectiveness of the selected
parameters. The dissolution of gypsum were examined in two parts at
low and high temperatures. The experimental results were
successfully correlated by linear regression using Statistica program.
Dissolution curves were evaluated shrinking core models for solidfluid
systems. The activation energy was found to be 34.58 kJ/mol
and 44.45 kJ/mol for the low and the high temperatures. The
dissolution of gypsum was controlled by chemical reaction both low
temperatures and high temperatures.

• Turan Çalban
• Nursel Keskin
• Sabri Çolak
• Soner Kuşlu

• Diammonium hydrogen phosphate
• Dissolution
• Gypsum
• Kinetics.

[1] Anonim, “Türkiye’nin Doğal Kaynakları” http://www.marbleport.com.
pp. 1-10.
[2] Anonim, “Jips Bugünü ve Geleceği, Metal Teknoloji Platformu
Oluşturma Çalıştayı”, Tübitak, Ankara, 2003, pp. 1-74.
[3] Anonim, “Türkiye Sanayi Sektörünün Değerlendirilmesi”, Türkiye
Cumhuriyeti Bilim Sanayi ve Teknoloji Bakanlığı, Ankara, 2011, pp. 1-
55.
[4] M. Yeşilyurt, S. Çolak, T. Çalban and Y. Genel, “Determination of the
optimum conditions for the dissolution of colemanite in H3PO4
solutions”, Ind. Eng. Chem. Res., vol.44, 2005, pp. 3761-3765.
[5] T. Çalban, S. Çolak and M. Yeşilyurt, “Optimization of Leaching of
Copper from Oxidized Copper Ore in NH3-(NH4)2SO4 Medium”,
Chem. Eng. Comm., vol. 192, 2005, pp. 1515-1524.
[6] M. Sokic, B. Markovic, V. Matkovic, D. Zivkovic, N. Strbac and J.
Stojanovic, “Kinetics and Mechanism of Sphalerite Leaching by Sodium
Nitrate in Sulphuric Acid Solution”, Journal of Mining and Metallurgy,
vol. 48 (2), 2012, pp. 185-195.
[7] B. Xue, Y. Shao-hua, L. Yao and W. Wen-yuan, “Leaching Kinetics of
Bastnaesite Concentrate in HCl Solution”, Trans. Nonferrous Met. Soc.
of China, vol. 21, 2011, pp. 2306-2310.
[8] T. Çalban, B. Kaynarca, S. Kuşlu, S. Çolak, “Leaching kinetics of
Chevreul’s salt in hydrochloric acid solutions”, Journal of Ind. and Eng.
Chem., vol. 20, 2014, pp. 1141-1147.
[9] T. Çalban, E. Kavcı, “Removal of Calcium from Soda Liquid Waste
Containing Calcium Chloride”, Energy Sources: Part A, vol. 32, 2010,
pp. 407-418.
[10] H. Gülensoy, “Kompleksometrinin Temelleri ve Kompleksometrik
Titrasyonlar”, Fatih Yayınevi, İstanbul, 1984.
[11] E. Kavcı, T. Çalban, S. Kuşlu, S. Çolak, “Leaching kinetics of ulexite in
sodium hydrogen sulphate solutions”, Journal of Industrial an
Engineering Chemistry, vol. 20, 2014, 2625.
[12] O. Levenspiel, “Chemical Reaction Engineering”, Wiley, 2nd edition:
NewYork, 1972.
[13] F. Habashi, “Kinetics of Metallurgical Processes”, 1999.
[14] A. Ekmekyapar, E. Aktaş, A. Künkül, N. Demirkıran, “Investigation of
leaching kinetics of copper from malachite ore in ammonium nitrate
solutions”, Metallurgical and Materials Transactions B, vol. 43B, 2012,
p. 764.
[15] B. Dönmez, F. Demir, O. Lacin, “Leaching kinetics of calcined
magnesite in acetic acid solutions”, Journal of Industrial an Engineering
Chemistry, vol. 15, 2009, p. 865.
[16] S. Kuşlu, F. Ç. Dişli, S. Çolak, “Leaching kinetics of ulexite in borax
pentahydrate solutions saturated with carbon dioxide”, Journal of
Industrial an Engineering Chemistry, vol. 16, 2010, p. 673.
[17] R. Guliyev, S. Kuşlu, T. Çalban, S. Çolak, “Leaching kinetics of
colemanite in potassium hydrogen sulphate solutions”, Journal of
Industrial and Engineering Chemistry, vol. 18, 2012, p. 38.