2001 Fiscal Year Final Research Report Summary
Investigation for energy state of zeolites
| Project/Area Number |
12640468
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Petrology/Mineralogy/Science of ore deposit
|
|---|
| Research Institution | Yamaguchi University |
|---|
Principal Investigator |
MIZOTA Tadato Yamaguchi University, Faculty of Engineering, Professor, 工学部, 教授 (10018666)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
FUJIWARA Keiko Yamaguchi University, Faculty of Engineering, Technical Official, 工学部, 教務員 (50253175)
NAKATSUKA Akihiko Yamaguchi University, Faculty of Engineering, Assistant, 工学部, 助手 (80294651)
NAKAYAMA Noriaki Yamaguchi University, Faculty of Engineering, Associate Professor, 工学部, 助教授 (00164369)
|
|---|
| Project Period (FY) |
2000 – 2001
|
| Keywords | zeolite / water / hydration enthalpy / entropy / hydration / vapor pressure / LTA / CHA |
|---|
| Research Abstract |
Cyclic operation of a zeolite-water heat pump has been done successfully, and clarified that water molecule in zeolite, zeolitic water, as an independent component has very large heat capacity as much as almost twice of that of pure water which has the largest specific heat capacity of materials. Enthalpy increment of zeolitic water by heating from 25℃ to 100℃ was 10.6kJ per one mole of H_2O, whereas that of pure water is 5.25kJ. The calculation was done based on an ideal case without dehydration of zeolite during heating, as the real heating accompanies dehydration by 3-4% up to 100℃, when the zeolite is under the vapor pressure equilibrated with water at 25℃. As the enthalpy values of hydration is rater constant to be -65kJ/mol for various hydration levels of Mg53-A zeolite, the value is thought to be almost equal to the differential enthalpy. This proves that the large heat capacity reflects the nature of the zeolitic water in the void of the zeolite, that is, drastic- energetic change of zeolitic water there. The fact supports the unique function of the zeolite-water heat pump system for effective use of low temperature heat sources. The low entropy of zeolitic water was proved also by the experiment of equilibrium vapor pressure-temperature relations. Crystal structures of chabazite as well as the sites of water molecule were analyzed by X-ray single crystal structure analyses of both the raw chabazite and the dehydrated sample.
|
Research Products
(24 results)
