P507 test method for content and Diacid
& Reagents and solutions
Sodium hydroxide standard titration solution: CNaOH=0.1mol/L
Ethanol solution: 75% (v/v)
& Instruments and equipment.
1 Automatic potentiometric titrator (Aptar 916)
(a) Potential measurement resolution: 0.1mV;
(b) Potential measurement range: ±2000mV.
(c) Minimum feed volume: 0.001mL;
(d) Liquid addition error: not more than ±3%;
(e) Electromagnetic stirring function: Stirring intensity: 0.001mL.
(f) Electromagnetic stirring function: stirring intensity can be
2 One-millionth balance
& Measurement step
Calibrate the electrode according to the requirements of pH meter.
Accurately weigh 0.4800-0.5200g (accurate to 0.0001g) of P-507 in a 100ml beaker,
add 50ml of 75% ethanol to dissolve it, put it into the test position of the automatic
potentiometric titrator, immerse the stirring paddle and electrode connected to the
automatic potentiometric titrator into the solution, and then turn on the titration
program of P-507. Stir for several 1-minute periods and then titrate with a 0.1 mol/L
standard solution of sodium hydroxide.
The instrument calculator determines the volume of sodium hydroxide solution
consumed at the time of the transition based on the slope, which is noted as V1;
The volume of standard sodium hydroxide solution consumed in the titration to pH
10.4 is recorded as V2;
Calculation of Results
The P-507 content and the content of dibasic acid in the sample are calculated according to the following formulas.
P-507 Content=
Diacid content =
Remark:
C—Molar concentration of sodium hydroxide standard solution, mol/L;
V1—Volume of sodium hydroxide standard solution consumed during titration to the first breakthrough point, ml;
V2–volume of sodium hydroxide standard solution consumed when titrating to PH=10.4, ml;
m— P-507 sample mass, g;
0.3064–Millimolar mass of P-507, g/mmol (according to the international relative atomic mass in 2011);
0.1942 — millimolar mass of dibasic acid, g/mmol (at 2011 international relative atomic mass);
P507 test method for Phase separation speed
& Reagents and solutions
260# solvent oil, rare earth extraction solution, 5 mol/L sodium hydroxide solution
& Instruments and equipment
Stopwatch, 205ml dispensing funnel
& Measurement steps:
Add 36mL of P-507 sample, 36mL of solvent oil and 7.8mL of 5mol/L sodium hydroxide
solution into the 250mL dispensing funnel and shake well for 3-5min.
Add 15mL of rare-earth material into the separatory funnel, and continue to shake for 3-5min.
Open the stopper of the separatory funnel, start to stand, and start the stopwatch timing.
Until the interface between the oil and water phases is clear and the volume of the two phases
no longer changes, record the resting time at this point that is the speed of extraction of the P-507 samples.