%0 Journal Article
	%A Y. Shiren and  M. Masuzawa and  H. Ohkura and  T. Yamagata and  Y. Aman and  N. Kobayashi
	%D 2015
	%J International Journal of Chemical and Molecular Engineering
	%B World Academy of Science, Engineering and Technology
	%I Open Science Index 103, 2015
	%T Durability Enhancement of CaSO4 in Repetitive Operation of Chemical Heat Pump
	%U https://publications.waset.org/pdf/10001584
	%V 103
	%X An important problem for the CaSO4/CaSO4･1/2H2O
Chemical heat pump (CHP) is that the material is deactivated through
repetitive reaction between hydration and dehydration in which the
crystal phase of the material is transformed from III-CaSO4 to
II-CaSO4. We investigated suppression on the phase change by adding
a sulfated compound. The most effective material was MgSO4. MgSO4
doping increased the durability of CaSO4 in the actual CHP repetitive
cycle of hydration/dehydration to 3.6 times that of undoped CaSO4.
The MgSO4-doped CaSO4 showed a higher phase transition
temperature and activation energy for crystal transformation from
III-CaSO4 to II-CaSO4. MgSO4 doping decreased the crystal lattice
size of CaSO4･1/2H2O and II-CaSO4 to smaller than that of undoped
CaSO4. Modification of the crystal structure is considered to be related
to the durability change in CaSO4 resulting from MgSO4 doping.
	%P 803 - 807