What is a Thermogravimetric Analyzer

What is a thermogravimetric analyzer TG or TGA? The application of the principle of thermogravimetric analysis is organized by Shanghai Farui Instruments for your reference. Thermogravimetric analysis (TG or TGA) refers to a thermal analysis technique that measures the relationship between the mass and temperature change of the sample under program-controlled temperature, which is used to study the thermal stability and composition of the material. TGA is a commonly used detection method in research and development and quality control. In actual material analysis, thermogravimetric analysis is often used in conjunction with other analysis methods to conduct comprehensive thermal analysis and comprehensively and accurately analyze materials.

According to the definition of the International Confederation for Thermal Analysis (ICTA), thermogravimetric analysis refers to the technology of measuring the relationship between the mass and temperature of a substance when the temperature is controlled by a program. It is worth mentioning here that it is defined as a change in mass rather than a change in weight. It is based on the fact that when a strong magnetic material reaches the Curie point under the action of a magnetic field, although there is no change in mass, there is an apparent weight loss. Thermogravimetric analysis refers to the observation of the actual mass change of the sample during the heating process.

Thermogravimetric Analyzer
The instrument used for thermogravimetric analysis is a thermobalance. Its basic principle is that the displacement of the balance caused by the change in sample weight is converted into electromagnetic quantity. This tiny amount of electricity is amplified by an amplifier and sent to a recorder for recording; and the amount of electricity is proportional to the weight change of the sample. When the substance being measured sublimates, vaporizes, decomposes into gas or loses crystal water during heating, the mass of the substance being measured will change. At this time, the thermogravimetric curve is not a straight line but has a decrease. By analyzing the thermogravimetric curve, we can know at what degree the substance being measured changes, and based on the weight loss, we can calculate how much substance is lost (such as crystal water in CuSO4·5H2O). From the thermogravimetric curve, we can know that the 5 crystal waters in CuSO4·5H2O are removed in three steps. TGA can obtain information on the thermophysical properties of the sample caused by the thermal changes.

Thermogravimetric analysis can generally be divided into two categories: dynamic method and static method.

⒈Static method: including isobaric mass change measurement and isothermal mass change measurement. Isobaric mass change measurement refers to a method of measuring the relationship between the equilibrium mass and temperature of a substance under a constant volatile partial pressure under program-controlled temperature. Isothermal mass change measurement refers to a method of measuring the relationship between the mass and temperature of a substance under constant temperature conditions. This method is highly accurate and time-consuming.
Thermogravimetric analyzer structure

2. Dynamic method: It is what we often call thermogravimetric analysis and differential thermogravimetric analysis. Differential thermogravimetric analysis is also called derivative thermogravimetry (DTG), which is the first-order derivative of the TG curve to temperature (or time). The DTG curve is obtained by plotting the mass change rate (dm/dt) of the substance against temperature T (or time t). Thermogravimetric
analysis can study the changes in crystal properties, such as physical phenomena of substances such as melting, evaporation, sublimation and adsorption; study the thermal stability, decomposition process, dehydration, dissociation, oxidation, reduction, quantitative analysis of components, the influence of additives and fillers, water and volatiles, reaction kinetics and other chemical phenomena of substances. It is

widely used in research and development, process optimization and quality control in various fields such as plastics, rubber, coatings, pharmaceuticals, catalysts, inorganic materials, metal materials and composite materials. The

important feature of thermogravimetry is its strong quantitativeness, which can accurately measure the mass change and the rate of change of the substance. It can be said that as long as the weight of the substance changes when heated, the thermogravimetric method can be used to study its change process. Thermogravimetry has been applied in the following areas:

⑴ Thermal decomposition of inorganic, organic and polymer substances;
⑵ Corrosion of metals by various gases at high temperatures;
⑶ Solid-state reactions;
⑷ Calcination and smelting of minerals;
⑸ Distillation and vaporization of liquids;
⑹ Pyrolysis of coal, petroleum and wood;
⑺ Determination of moisture content, volatile matter and ash content;
⑻ Sublimation process;
⑼ Dehydration and moisture absorption;
⑽ Research on explosive materials;
⑾ Research on reaction kinetics;
⑿ Discovery of new compounds;
⒀ Adsorption and desorption;
⒁ Determination of catalytic activity;
⒂ Determination of surface area;
⒃ Research on oxidation stability and reduction stability;
⒄ Research on reaction mechanism.
18. It can also be used as a characterization method to measure the pH value of solid surfaces.
Technical parameters:
1. Temperature range: room temperature ~ 1150 ℃
2. Temperature resolution: 0.1 ℃
3. Temperature fluctuation: ± 0.1 ℃
4. Heating rate: 1 ~ 80 ℃ / min
5. Temperature control mode: heating, constant temperature, cooling
6. Cooling time: 15min (1000 ℃ ... 100 ℃)
7. Balance measurement range: 1mg ~ 2g, can be expanded to 30g
8. Resolution: 0.1μg
9. Constant temperature time: 0 ~ 300min arbitrarily set
10. Display mode: Chinese characters large screen LCD display
11. Atmosphere device: built-in gas flow meter, including two-way gas switching and flow control

(atmosphere: inert, oxidizing, reducing, static, dynamic)

12. Software: intelligent software can automatically record TG curve for data processing, print experimental reports
13. Data interface: RSS-232 interface, dedicated software (software is upgraded for free from time to time)
14. Power supply: AC220V 50Hz