Precipitated barium sulfate is a white powdery inorganic compound with the chemical formula BaSO4, which is often used in the preparation of barium salts, chemical reagents, paints, rubber, plastics and other fields.
Detection performance
It has the characteristics of high density, heat resistance, acid and alkali corrosion resistance, etc. The following properties need to be tested in the application:
Particle size distribution: The size distribution of powder particles directly affects its performance and use effect.
Particle size and shape: The shape of particles has an important impact on the fluidity, dispersion and stability of the coating.
Specific surface area: It affects the chemical reaction rate, surface energy, wettability, adhesion and other properties of the powder.
Sedimentation volume: It reflects the density and sedimentation velocity of precipitated barium sulfate, which can indirectly reflect its particle size.
Volatile content: detect its moisture content, impurity content, etc.
Acid-soluble substance content: Detect the acid-soluble substance content, which has an impact on the use scene and quality requirements.
The above properties can be detected and analyzed by particle size analyzers, specific surface area meters, sedimentation volume meters, ovens, acidity meters and other equipment.
Detection Indicator
Precipitated barium sulfate is usually used as a white pigment or filler, and its performance testing needs to pay attention to the following aspects:
| performance | Detection Indicator |
|---|---|
| chemical purity | BaSO4 content |
| physical properties | Particle size distribution, specific surface area, oil absorption value |
| optical properties | Powder brightness, hiding power, color difference |
Detection method
The specific detection method is as follows:
Chemical purity: Using the gravimetric method, add the sample to barium nitrate to form a precipitate, then dry it in an electric furnace and weigh it, and calculate the mass fraction of BaSO4 in the precipitate.
Physical properties:
Particle size distribution: use laser particle size analyzer, electron microscope and other equipment to measure the particle size distribution of precipitated barium sulfate.
Specific surface area: Measure the specific surface area of precipitated barium sulfate by gas adsorption method (such as BET method).
Oil absorption value: According to ISO standard or national standard, the oil absorption value of precipitated barium sulfate is determined by soaking in cetyltrimethylammonium bromide solution.
Optical properties:
Powder brightness: measure the reflectance of precipitated barium sulfate with reflectance spectrometer and other instruments, and calculate the powder brightness.
Hiding Power: Hiding power is evaluated by comparing the transmittance or transmittance of samples coated with precipitated barium sulfate to a standard sample.
Color difference: Use color difference meter or Colorimeter to measure the color parameters of precipitated barium sulfate, such as L*, a*, b* value.
how to detect
Appearance inspection: observe the shape, size, color and other characteristics of the sample visually or through a microscope.
Particle size distribution: Measure parameters such as the average diameter and particle size distribution of particles in the sample by particle size analyzers or microscopes and other testing instruments.
Purity testing: use chemical analysis methods or instruments to analyze the main components and impurities in the sample to determine the purity of the sample.
Determination of specific surface area: use specific surface area meter and other testing instruments to measure the specific surface area of the sample, and evaluate the activity and reaction performance of the sample.
Solubility Determination: Evaluate the chemical properties of a sample by observing its solubility at different temperatures.
Chromaticity measurement: Use a photometer and other instruments to measure the absorbance of the sample to determine the chromaticity of the sample.
Density determination: Measure the density of the sample by testing instruments such as a densitometer to evaluate its physical properties.
Determination of chemical stability: use chemical analysis methods or instruments to measure the chemical stability of the sample, so as to determine its stability under different conditions.
