The use of graphite powder covers almost all fields of […]
The use of graphite powder covers almost all fields of industry, and is a necessity and consumable in the industrial field. The reason why graphite powder can cover the entire industrial field is inseparable from the superior performance of graphite powder. Of course, graphite powder is in various fields. The performance used is also different. According to its performance, processing technology, application fields, specifications, etc., graphite powder can be divided into several types, and ultrafine graphite powder is one of them.
When I first came into contact with and knew, the ultra-fine graphite powder thought that the ultra-fine graphite powder is the graphite powder with relatively fine particle size in the graphite powder product. With the deep understanding and learning of the graphite powder, I know the ultra-fine graphite powder and The fundamental difference between other graphite powders is the different processing techniques. Ultrafine graphite powder is also made of natural flake graphite or flake graphite powder, which can also be called scale superfine graphite powder.
Ultrafine graphite powder has the same specifications as other graphite powder products. The specifications of ultrafine graphite powder are also 100 mesh, 200 mesh, 325 mesh, 400 mesh, 600 mesh, 800 mesh, 1200 mesh, 3500 mesh. 6000 mesh, 8000 mesh, etc. The advantage of Huatai Graphite's ultrafine graphite powder lies in its different production processes. Huatai Graphite is pulverized by a self-developed jet mill. Compared with traditional mills, the pulverization effect is better, the ultra-fine graphite powder particles are uniform, and the ultra-fine graphite powder is also used more widely than other graphite powders of the same specification. . And the graphite tube is used as the resistance heating element, and the temperature is rapidly increased after energization, so that the sample reaches the atomization purpose.
It consists of a heating power supply, a protective gas control system and a graphite tubular furnace. An external power source is applied to both ends of the graphite tube to supply the atomizer energy, and the current is generated through the graphite tube to a temperature of up to 3000 ° C, so that the element to be placed in the graphite tube is measured. It becomes the ground state atomic vapor. The protective gas control system controls the shielding gas. The instrument starts, the protective gas Ar flows, and the air is burned, and the Ar gas flow is cut off. The Ar gas in the outer gas path flows along the outer wall of the graphite tube to protect the graphite tube. Not ablated, the internal Ar gas from the tube two
The end flows to the center of the tube and flows out of the central hole of the tube to effectively remove the matrix vapor generated during the drying and ashing process while protecting the atom that has been atomized from oxidation.
In the atomization stage, the aeration is stopped to prolong the average residence time of the atoms in the absorption zone to avoid dilution of the atomic vapor. In the graphite furnace atomization system, the flame is replaced by an electrically heated graphite tube placed under an argon atmosphere. Argon prevents the graphite tube from rapidly oxidizing at high temperatures and removes matrix components and other interfering substances from the optical path during the drying and ashing stages. A small amount of sample (1 to 70 mL, usually around 20 mL) is added to the heat. The pyrolytic coating on the graphite tube can effectively prevent the oxidation of the graphite tube, thereby prolonging the service life of the graphite tube. At the same time, the coating can also prevent the sample from invading the graphite tube to improve sensitivity and repeatability.
The graphite tube is heated by current, and the current is controlled by a programmable control circuit, so that the sample in the graphite tube can be heated in a series of heating steps during heating to remove the solvent and most of the matrix components and then atomize the sample. The free state of the ground state is generated. The decomposition of the molecule depends on the atomization temperature, the heating rate and the environment around the wall of the hot graphite tube.