Solubility of potassium oxalate

Details:

Name: potassium oxalate

Molecular formula: c2h2k2o5

Molecular weight: 184.23

MDL No.: mfcd00150033

EINECS No.: 209-506-8

physical property:

1、 Physical property data

2. Properties: colorless crystal or white crystalline powder. tasteless

3. Density (g / ml, 25 / 4 ℃): 2.13

4. Relative vapor density (g / ml, air = 1)

5. Melting point (℃): (kPa)

6. Boiling point (℃, atmospheric pressure)

7. Boiling point (℃, 5.2kpa)

8. Refractive index:

9. Flash point (℃)

10. Specific rotation (o): 0

11. Spontaneous combustion point or ignition temperature (℃)

12. Vapor pressure (kPa, 25 ℃):

13. Saturated vapor pressure (kPa, 60 ℃):

14. Heat of combustion (kJ / mol)

15. Critical temperature (℃)

16. Critical pressure (kPa)

17. Logarithm of oil-water (octanol / water) partition coefficient:

18. Upper explosion limit (%), V / V:

19. Lower explosive limit (%), V / V:

20. Solubility: soluble in water, slightly soluble in ethanol

chemical property:

1. It is easily weathered in dry air. When heated to about 160 ℃, crystal water is lost. Its solubility in 100g water is 28.7g (0 ℃) and 83.2g (100 ℃). It can be weathered and become anhydrous when heated.

Preparation route:

1. Oxalic acid dihydrate was dissolved in water and heated to 80 ℃. Add potassium carbonate in several times under stirring until the solution is alkaline. Filter the solution, evaporate the filtrate at 80 ℃ until crystallization occurs, cool it down to 20 ℃, absorb and filter out the crystallization, wash with water and dry to obtain potassium oxalate.

2. Potassium oxalate monohydrate is obtained by neutralizing the aqueous solution of oxalic acid or potassium hydrogen oxalate with potassium hydroxide or potassium carbonate and cooling. Anhydrous potassium oxalate is obtained by drying the monohydrate at 160 ℃.

In the refining method, 100g potassium oxalate was dissolved in 500ml water, 20ml 10% sodium hydroxide solution (mass fraction) was added, air was blown into the solution for 24-36h, the solution was filtered if necessary, and then 1000-1200ml ethanol was added to the filtrate to precipitate fine crystals. The crystals were filtered and washed with a small amount of ethanol and ether, and then air dried.

Main uses:

1. Analytical reagent, used to prevent blood coagulation, pharmaceutical industry, film development, etc.