Method for producing package including hydrogen sulfide sustained release agent, hydrogen sulfide sustained release agent, hydrogen sulfide sustained release composite, and method for generating hydrogen sulfide using same

1. A method for producing a package comprising a layered double hydroxide having HS − and/or S k 2− (wherein k represents a positive integer) intercalated among layers, and a packaging material hermetically housing the layered double hydroxide, the method comprising:

preparing a layered double hydroxide having an anion other than HS − and/or S k 2− (wherein k represents a positive integer) intercalated among layers, and a solvent;

making the solvent to contain HS − and/or S k 2− under a nitrogen gas or rare gas atmosphere to provide a solution;

bringing the layered double hydroxide having an anion other than HS − and/or S k 2− (wherein k represents a positive integer) intercalated among layers into contact with the solution under a nitrogen gas or rare gas atmosphere;

separating a solid matter after the contact from the solution, and washing and drying the solid matter, under a nitrogen gas or rare gas atmosphere; and

sealing the solid matter after drying in a packaging material.

2. The method for producing the package according to claim 1 , wherein the layered double hydroxide having an anion other than HS − and/or S k 2− intercalated among layers contains CO 3 2− as the anion, and at least a part of the CO 3 2− is removed from an interlayer of the layered double hydroxide, which is then brought into contact with the solvent containing HS − and/or S k 2− .

3. The method for producing the package according to claim 1 , wherein the method further comprises, preceding making the solvent to contain HS − and/or S k 2− , decreasing concentrations of oxygen and carbon dioxide in the solvent, and the solid matter is washed with a solvent having decreased concentration of oxygen and carbon dioxide.

4. The method for producing the package according to claim 1 , wherein the solvent is made to contain HS − and/or S k 2− by mixing a compound represented by the following general formula (2):

MH p S q ·m H 2 O  (2)

wherein in the formula (2), M represents an alkali metal or an alkaline earth metal; p represents 0 or 1; q represents a number satisfying 0.5≤q≤6.0; and m represents a number varying depending on a humidity of an environment.

5. The method for producing the package according to claim 1 , wherein the solid matter after the contact is subjected to a treatment of changing a distribution state of HS − and/or S k 2− .

6. The method for producing the package according to claim 5 , wherein the treatment includes a treatment of washing the solid matter with a liquid containing water.

7. The method for producing the package according to claim 5 , wherein the treatment includes a treatment of bringing the solid matter after the drying into contact with oxygen.

8. The method for producing the package according to claim 5 , wherein the treatment includes a homogenization treatment of a compositional distribution of the solid matter after the drying.

9. The method for producing the package according to claim 5 , wherein the treatment includes a treatment of releasing a part of HS − and/or S k 2− (wherein k represents a positive integer) contained in the solid matter from the solid matter after the drying as hydrogen sulfide.

10. A method for producing a package comprising a layered double hydroxide having HS − and/or S k 2− (wherein k represents a positive integer) intercalated among layers, and a packaging material hermetically housing the layered double hydroxide, the method comprising:

preparing an aqueous solution containing plural kinds of metal ions, and an alkali solution containing HS − and/or S k 2− (wherein k represents a positive integer);

mixing the aqueous solution and the alkali solution under a nitrogen gas or rare gas atmosphere to provide a precipitate;

ripening the solution containing the precipitate under a nitrogen gas or rare gas atmosphere;

separating the precipitate after the ripening from the solution, and washing and drying the precipitate, under a nitrogen gas or rare gas atmosphere; and

sealing a solid matter after the drying in a packaging material.

11. A hydrogen sulfide sustained release agent comprising a layered double hydroxide having HS − and/or S k 2− (wherein k represents a positive integer) intercalated among layers,

wherein when the hydrogen sulfide sustained release agent is conducted to a H 2 S release experiment, a hydrogen sulfide concentration increases to a maximum value, and then a concentration thereof gradually reduces; and

the hydrogen sulfide in a concentration of 1/100 or more relative to the maximum value is released continuously for 30 minutes or more.

12. The hydrogen sulfide sustained release agent according to claim 11 , wherein the layered double hydroxide is represented by the following general formula (1):

Q x R(OH) 2(x+1) {(HS − ,0.5S k 2− ) y Z t }·n H 2 O  (1)

wherein in the formula (1), Q represents a divalent metal ion; R represents a trivalent metal ion; Z represents an anion other than HS − and/or S k 2− ; x, y, and t represent numbers satisfying 1.8≤x≤4.2, 0.01≤y≤2.0, and 0≤t≤1.0; and n represents a number varying depending on a humidity of an environment.

13. The hydrogen sulfide sustained release agent according to claim 11 , wherein the layered double hydroxide is a granulated material or a powder compact material.

14. The hydrogen sulfide sustained release agent according to claim 11 , wherein the layered double hydroxide is mixed with an extender or a diluent.

15. The hydrogen sulfide sustained release agent according to claim 11 , wherein the layered double hydroxide has at least HS − intercalated among layers.

16. The hydrogen sulfide sustained release agent according to claim 11 , wherein said concentration is more than 0.35 ppm.

17. A method for generating hydrogen sulfide, comprising using the hydrogen sulfide sustained release agent according to claim 11 .

18. A hydrogen sulfide sustained release composite comprising the hydrogen sulfide sustained release agent according to claim 11 housed in a porous cover or a porous container.

19. A method for generating hydrogen sulfide, comprising using the hydrogen sulfide sustained release composite according to claim 18 .