Evaluation Method of Water Dispersibility of Titanium Dioxide

1. Simple Method

Take a 500 ml transparent glass beaker and fill it with clean water. Take about 5 grams of titanium dioxide with a small spoon and stir it for 10 minutes with a glass rod. Then observe the sedimentation of titanium dioxide. The faster the sedimentation (stratification), the worse the water dispersion. On the contrary, the slower the sedimentation (stratification), the better the water dispersion.

2. Standard Method: Rules for the Determination of Water Dispersibility

1. Weighing

The titanium dioxide sample was weighed 15g and put into a 500ml beaker pre-loaded with 285 ml deionized water.

2. Dispersion

Stir the beaker on a magnetic stirrer for 30 minutes.

3. Determination of initial slurry

Immediately take 10 ml of the slurry after oscillation and put it into a constant weight evaporating dish, weigh the slurry weight (W1), then put it in a 140 C oven for more than 4 hours to the constant weight, and weigh the residual weight (W2) after cooling.

4. Static Settlement

The remaining dispersed slurry is loaded into the measuring cylinder to keep the liquid level 200 mm, placed on the flat operating table and settled for 5 hours.

5. Dispersion Sampling

Use pipette to inhale the stationary dispersed liquid from the liquid level to the bottom of 30 mm in 250 ml beaker (do not shake the measuring cylinder).

6. Drying and weighing of disperse solution

Drain the dispersed liquid from a 10ml shaking 250ml beaker with a pipette and weigh the slurry weight (W3) in an evaporating dish of constant weight.

Ibid. bake for more than 4 hours. Cool and weigh the residual weight (W4).

7. Computation: W4*W1

Water Dispersibility (%)= -- -*100

W2 * W3

Among them: W1: Weight of initial slurry 10 ml before static setting

Content of Titanium Dioxide in W2:W1

W3: Slurry weight after 5 hours

Content of Titanium Dioxide in W4:W3