Investigations on Dehydration Process of Trisodium Phosphate Dodecahydrate

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Abstract

The dehydration process of trisodium phosphate dodecahydrate (Na₃PO₄·12H₂O) from 303.15 K to 413.15 K was investigated by using thermogravimetry (TG), differential scanning calorimetry (DSC), power X-ray diffraction (PXRD) and scanning electron micrograph (SEM). It was found that 11 mol crystal water of trisodium phosphate dodecahydrate was dehydrated from 303.15 K to 393.15 K and the process included multi-step reactions. Activation energies of dehydration at different dehydration rate were calculated by Ozawa equation and Friedman equation, respectively and a good identity of results was reached. The process of dehydration consisted of four steps, which were different in dehydration mechanism. The PXRD and SEM of dehydration products at different temperature showed that it was channel-type inclusion hydrate and crystal structure has transformed during the process of dehydration.

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	Articles by authors
	Zhang Gong
	Dang Leping
	Wei Hongyuan

Keywords： trisodium phosphate dodecahydrate； dehydration； TG/DSC； PXRD； SEM

Received 2016-04-05;

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Zhang Gong, Dang Leping, Wei Hongyuan.Investigations on Dehydration Process of Trisodium Phosphate Dodecahydrate[J] Chemcial Industry and Engineering, 2018,V35(4): 46-51,65

[1] 张受谦. 化工手册[M]. 山东科学技术出版社, 1986
[2] 王颖莉. 高质量磷酸三钠生产工艺控制要点[J]. 无机盐工业, 2000, 32(4):37-38 Wang Yingli. Controlling points for process technology of high quality trisodium phosphate[J]. Inorganic Chemical Industry, 2000, 32(4):37-38(in Chinese)
[3] Seddon K R. Pseudopolymorph:A Polemic[J]. Crystal Growth & Design, 2004, 4(6):1087-1087
[4] Khankari R K, Grant D J W. Pharmaceutical hydrates[J]. Thermochimica Acta, 1995, 248(1):61-79
[5] Han J, Suryanarayanan R. Applications of pressure differential scanning calorimetry in the study of pharmaceutical hydrates. I. Carbamazepine dihydrate[J]. Arkivoc Online Journal of Organic Chemistry, 2012, 10(38):80-99
[6] Steiner T, Koellner G. Crystalline beta-cyclodextrin hydrate at various humidities:Fast, continuous, and reversible dehydration studied by X-ray diffraction[J]. Journal of the American Chemical Society, 1994, 116(12):5122-5128
[7] Morris R E, Burton A, Bull L M, et al. SSZ-51-A new aluminophosphate zeotype:Synthesis, crystal structure, NMR, and dehydration properties[J]. Cheminform, 2004, 35(40):7-9
[8] Santos A V D, Matos J R. Dehydration studies of rare earth p-toluenesulfonate hydrates by TG/DTG and DSC[J]. Journal of Alloys & Compounds, 2002, 344(s1/2):195-198
[9] Duan Y, Li J, Yang X, et al. Kinetic analysis on the non-isothermal dehydration by integral master-plots method and TG-FTIR study of zinc acetate dihydrate[J]. Journal of Analytical & Applied Pyrolysis, 2008, 83(1):1-6
[10] Lee S B, Fasina O. TG-FTIR analysis of switchgrass pyrolysis[J]. Journal of Analytical & Applied Pyrolysis, 2009, 86(1):39-43
[11] Yonemochi E, Hoshino T, Yoshihashi Y, et al. Evaluation of the physical stability and local crystallization of amorphous terfenadine using XRD-DSC and micro-TA[J]. Thermochimica Acta, 2005, 432(1):70-75
[12] Ghule A, Murugan R, Chang H. Thermo-Raman studies on dehydration of Na₃PO₄·12H₂O[J]. Thermochimica Acta, 2001, 371(1/2):127-135
[13] Ekeren P J V. Handbook of thermal analysis and calorimetry[J]. Thermochimica Acta, 2003, 407(1):121-123
[14] Ozawa T. A new method of analyzing thermogravimetric data[J]. Bulletin of the Chemical Society of Japan, 1965, 38(11):1881-1886
[15] Vyazovkin S. A unified approach to kinetic processing of nonisothermal data[J]. International Journal of Chemical Kinetics, 1996, 28(2):95-101
[16] Friedman H L. Kinetics of thermal degradation of cha-forming plastics from thermogravimetry, application to a phenolic plastic[J]. Journal of Polymer Science Part C Polymer Symposia, 2007, 6(1):183-195
[17] Ozawa T. Applicability of Friedman plot[J]. Journal of Thermal Analysis, 1986, 31(3):547-551
[18] Friedman H L. Kinetics and gaseous products of thermal decomposition of polymers[J]. Journal of Macromolecular Science:Part A-Chemistry, 1967, 1(1):57-79