Furnace thermogravimetric analysis

In a thermogravimetric analysis, the sample is placed in a small weighing boat attached to one arm of a specially designed electromagnetic balance and placed inside an electric furnace. The temperature of the electric furnace is slowly increased at a fixed rate of a few degrees per minute, and the sample s weight is monitored. 

When heated, many solids evolve a gas. For example, most carbonates lose carbon dioxide when heated. Because there is a mass loss, it is possible to determine the extent of the reaction by following the mass of the sample. The technique of thermogravimetric analysis involves heating the sample in a pan surrounded by a furnace. The sample pan is suspended from a microbalance so its mass can be monitored continuously as the temperature is raised (usually as a linear function of time). A recorder provides a graph showing the mass as a function of temperature. From the mass loss, it is often possible to establish the stoichiometry of the reaction. Because the extent of the reaction can be followed, kinetic analysis of the data can be performed. Because mass is the property measured, TGA is useful for... 

Thermogravimetric analysis (TGA) has been used to study the kinetics of feedstock pyrolysis. In this work, a Seiko 220 TG/DTA thermal balance system was used. The sample mass was 10.0 0.1 mg. The heating rate was 10 C/min. For each test, the nitrogen gas was first introduced in the furnace to remove the air. Then the pressure in the furnace was lowered by a vacuum pump to 13 kPa absolute. 

Thermogravimetric Analysis (TG). TG involves weighing a sample while it is exposed to heat. The chief use of this technique has been to study the thermal decomposition of polymeric materials and to accumulate kinetic information about such decomposition. A sample is suspended on a sensitive balance that measures the weight (Figure 1) as it is exposed to a furnace. Air, nitrogen, or another gas flows around the sample to remove the pyrolysis or combustion prod-... 

The thermal stability of polymers can be tested by thermogravimetric analysis (TGA). In this method, a sample of a few milligrams is deposited in a scale pan mounted on a furnace. TGA measurements can be done in isothermal mode by maintaining a certain temperature for a fixed period of time or in temperature cycling mode. Most often the data are obtained with a constant... 

During thermal debinding, the feedstocks are heated until the binder is removed via thermal decomposition. Hence, it is important to study the thermal decomposition of the binder in the presence of the powder. The TGA (thermogravimetric analysis) is usually used for this study. The samples would be heated at programmed heating rate with a stream of nitrogen gas purging the furnace s interior to reduce oxidation of the metal powder in the feedstocks. 

In thermogravimetric analysis (TGA), heat flows from the walls of the furnace to the specimen mostly by convection. Ideally, the furnace creates a uniform temperature region large enough to expose the specimen, the specimen container and the thermal sensor to the same conditions. Even under ideal conditions, however, the true specimen temperature may be quite different from that of the temperature sensor because the heat absorption rates are different for the thermal sensor and the specimen in its container. 

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