阅读说明：本技术 一种钛白粉吸油量测试方法 (Method for testing oil absorption of titanium dioxide ) 是由 陈冲 吴彭森 和奔流 周春勇 谢鑫伟 刘不尽 于 2021-06-29 设计创作，主要内容包括：本发明属于钛白粉生产技术领域,具体公开了一种钛白粉吸油量测试方法,包括以下步骤：1)将多种已知吸油量的钛白粉分别与精制亚麻仁油混合,打浆分散,得到浆料,测试各浆料的粘度值；2)根据各浆料的粘度值和吸油量,拟合出两者的关系式；3)在与步骤1)相同的条件下,测试待测钛白粉的粘度值；4)将待测钛白粉的粘度值带入步骤2)所得的关系式中,得到待测钛白粉的吸油量。本发明方法可降低测试过程中人为操作引起的测试误差,提高测试重现性,缩短测试时间,减轻测试劳动强度。(The invention belongs to the technical field of titanium dioxide production, and particularly discloses a method for testing oil absorption of titanium dioxide, which comprises the following steps: 1) mixing a plurality of titanium pigment with known oil absorption with refined linseed oil respectively, pulping and dispersing to obtain pulp, and testing the viscosity value of each pulp; 2) fitting a relational expression of the viscosity value and the oil absorption of each slurry according to the viscosity value and the oil absorption of each slurry; 3) testing the viscosity value of the titanium dioxide to be tested under the same condition as the step 1); 4) and (3) substituting the viscosity value of the titanium dioxide to be detected into the relational expression obtained in the step 2) to obtain the oil absorption of the titanium dioxide to be detected. The method can reduce the test error caused by manual operation in the test process, improve the test reproducibility, shorten the test time and reduce the test labor intensity.)

1. A method for testing oil absorption of titanium dioxide is characterized by comprising the following steps:

1) mixing a plurality of titanium pigment with known oil absorption with refined linseed oil respectively, pulping and dispersing to obtain pulp, and testing the viscosity value of each pulp;

2) fitting a relational expression of the viscosity value and the oil absorption of each slurry according to the viscosity value and the oil absorption of each slurry;

3) testing the viscosity value of the titanium dioxide to be tested under the same condition as the step 1);

4) and (3) substituting the viscosity value of the titanium dioxide to be detected into the relational expression obtained in the step 2) to obtain the oil absorption of the titanium dioxide to be detected.

2. The method for testing oil absorption of titanium dioxide according to claim 1, wherein the refined linseed oil is stirred to carry out preliminary dispersion, and then the titanium dioxide is added, and the slurry is obtained by pulping and dispersion.

3. The method for testing oil absorption of titanium dioxide according to claim 1 or 2, wherein the mass ratio of the refined linseed oil to the titanium dioxide is 0.5-5: 1.

4. The method for testing oil absorption of titanium dioxide according to claim 2, wherein the stirring speed of the refined linseed oil in the preliminary dispersion is 300-600 r/min.

5. The method for testing oil absorption of titanium dioxide according to claim 2, wherein the titanium dioxide is added within 1min, the stirring speed for the pulping and dispersing is 1000-2000r/min, and the dispersing time is 3-20 min.

6. The method for testing oil absorption of titanium dioxide according to claim 1, wherein the testing of the viscosity value of the slurry is completed within 2min after the slurry is obtained.

Technical Field

The invention belongs to the technical field of titanium dioxide production, and particularly relates to a method for testing oil absorption of titanium dioxide.

Background

At present, the oil absorption test methods of titanium dioxide mainly comprise two methods: one is the adjustable cutter kneading method: weighing 10g of a test sample (accurate to 0.1g) in titanium dioxide, placing on a flat plate, dropwise adding refined linseed oil by using a burette, wherein the oil adding amount is not more than 10 drops each time, after the addition is finished, pressing and grinding by using an adjustable knife to enable oil to permeate into the test sample, and continuously dropwise adding at the speed until the oil and the test sample form a block. From this moment, each drop is added and then the mixture is fully ground by a knife, and when the mixture is formed into a paste with uniform consistency, the paste is just not cracked and broken and can be adhered to a flat plate, the end point is obtained. The oil consumption is recorded and the whole operation should be completed within 20-25 min.

The second method is the Gardner-Coleman method: adding titanium dioxide into a glass cup, slowly dripping refined linseed oil, kneading by using a knife or a glass rod, and obtaining the end point when the paste can flow into a mass.

The existing method for testing oil absorption by titanium dioxide has long testing time and low testing precision, because the factors influencing the accuracy of the test are more, such as the force intensity of operators, the time length, the judgment of a terminal point, the quality of linseed oil and the like all influence the test result.

Disclosure of Invention

Aiming at the situations in the prior art, the invention aims to provide a method for testing the oil absorption of titanium dioxide, which can reduce the test error caused by manual operation in the test process, improve the test reproducibility, shorten the test time and reduce the test labor intensity.

The oil absorption of the titanium dioxide is the oil absorption capacity of the titanium dioxide, and the higher the oil absorption, the larger the oil absorption capacity. The linseed oil is adopted in the traditional oil absorption test method, the linseed oil is also adopted in the invention, and the adsorption capacity of the titanium dioxide is consistent. Titanium dioxide with different oil absorption contents is uniformly dispersed in linseed oil according to the same solid content, if the oil absorption of the titanium dioxide is high, more linseed oil can be adsorbed in the titanium dioxide, and the free linseed oil in a dispersion system is reduced. The dispersion has a reduced content of free solvent and a high viscosity of the dispersion is ensured. From experimental data, the viscosity data obtained by adjusting factors such as solid content, dispersion strength and the like of the titanium dioxide has a linear relation with oil absorption. Based on the method, the oil absorption of the titanium dioxide is provided.

The invention provides a method for testing oil absorption of titanium dioxide, which comprises the following steps:

1) mixing a plurality of titanium pigment with known oil absorption with refined linseed oil respectively, pulping and dispersing to obtain pulp, and testing the viscosity value of each pulp;

2) fitting a relational expression of the viscosity value and the oil absorption of each slurry according to the viscosity value and the oil absorption of each slurry;

3) testing the viscosity value of the titanium dioxide to be tested under the same condition as the step 1);

4) and (3) substituting the viscosity value of the titanium dioxide to be detected into the relational expression obtained in the step 2) to obtain the oil absorption of the titanium dioxide to be detected.

According to the invention, the oil absorption of the titanium dioxide with known oil absorption can be obtained by adopting the traditional knife-adjusting kneading method, and the oil absorption of various titanium dioxides has gradient. Refined linseed oil is a specific product name and is commercially available.

Preferably, the refined linseed oil is stirred for primary dispersion, then the titanium dioxide is added, and the slurry is obtained after pulping and dispersion. Stirring and beating dispersion are carried out by adopting a high-speed dispersion machine.

According to the invention, the mixing of the titanium dioxide and the refined linseed oil is completed in a container, and the container can control the temperature of the slurry to be 5-30 ℃ and the volume to be 100-1000 mL.

In the invention, the mass ratio of the refined linseed oil to the titanium dioxide is 0.5-5: 1.

Preferably, the stirring speed for the primary dispersion of the refined linseed oil is 300-600 r/min.

Preferably, the adding time of the titanium dioxide is within 1min, the stirring speed of the pulping and dispersing is 1000-2000r/min, and the dispersing time is 3-20 min.

According to the invention, the viscosity value of the slurry is tested within 2min after the slurry is obtained. The viscosity values of the slurries were measured using a rotary viscometer.

In addition, the relational expression between the viscosity value and the oil absorption of the pulp is influenced by the proportion of the titanium dioxide and the refined linseed oil, the size of a dispersion container, the dispersion strength, the temperature and other factors. Therefore, the titanium dioxide to be measured needs to be measured by the same method for obtaining the relational expression, and the viscosity value is substituted into the relational expression, so that the accurate oil absorption value of the titanium dioxide can be obtained.

The operating steps and parameters not defined in the present invention can be selected conventionally according to the prior art.

Compared with the prior art, the invention has the following beneficial effects:

the method adopts instruments such as a high-speed dispersion machine, a rotary viscometer and the like to operate, and solves the problem of test errors caused in the operation process of different operators by fixing instrument parameters. And the oil absorption test range can be adjusted by adjusting the proportion of the refined linseed oil to the titanium dioxide.

Drawings

FIG. 1 is a plot of the oil absorption and viscosity values fitted to samples 1-5 from example 1.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments of the present invention, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments.

Example 1

The viscosity values of titanium dioxide samples 1, 2, 3, 4 and 5 with known oil absorption were measured by the following methods.

The specific method comprises the following steps: 1. accurately weighing 210g of refined linseed oil, pouring the refined linseed oil into a 500mL container, placing the container on a high-speed dispersion machine, fixing the container by using a clamp, starting the dispersion machine, and primarily dispersing the linseed oil at the rotation speed of 500 r/min; 2. accurately weighing 140g of titanium dioxide sample with known oil absorption, slowly pouring the titanium dioxide into the refined linseed oil by using a knife, wherein the addition of the titanium dioxide is completed within 1 min; 3. increasing the rotating speed of the dispersion machine to 1500r/min, and timing for 10 min; 4. and after the dispersion is finished, taking down the slurry, and testing the viscosity value of the slurry by using a rotary viscometer, wherein the step is finished within 2 min.

The oil absorption and viscosity values of samples 1 to 5 are shown in table 1, and the relationship between the oil absorption and viscosity values is fitted as y-447.28 x-4746.8, and a specific fitting curve is shown in fig. 1.

And measuring the viscosity value of the titanium dioxide sample A to be measured by adopting the method, wherein the viscosity value is 1020mPa & s, and substituting the viscosity value into the relational expression to obtain the titanium dioxide sample A with the oil absorption of 12.893g/100 g.

TABLE 1

Sample (I)	Sample 1	Sample 2	Sample 3	Sample No. 4	Sample No. 5
						Oil absorption (g/100g)	12.6	14.5	16.3	17.5	20.2
Viscosity (mPa. s)	980	1600	2680	2920	4360

Example 2

And (3) measuring the viscosity value of the titanium dioxide sample B to be measured by adopting the method in the embodiment 1, wherein the viscosity value is 3900mPa & s, and substituting the viscosity value into the relational expression obtained in the embodiment 1 to obtain the oil absorption of 19.332g/100 g.

Example 3

And (3) measuring the viscosity value of the titanium dioxide sample C to be measured by adopting the method in the embodiment 1, wherein the viscosity value is 2470mPa & s, and substituting the viscosity value into the relational expression obtained in the embodiment 1 to obtain the oil absorption of 16.135g/100 g.

The oil absorption of the titanium dioxide sample A, B, C was measured by the conventional knife-kneading method, and the obtained oil absorption values are shown in table 2.

TABLE 2

As can be seen from Table 2, the oil absorption measured by the method of the present invention is close to the value obtained by the knife-adjusting kneading method, and the requirement of the titanium dioxide industry on the accuracy of oil absorption index testing can be satisfied within the normal testing error range.

Having described embodiments of the present invention, the foregoing description is intended to be exemplary, not exhaustive, and not limited to the disclosed embodiments. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the illustrated embodiments.