Technical application of calcined zinc oxide

In order to improve the physical properties of raw zinc oxide extracted by zinc steam, such as direct zinc oxide and indirect zinc oxide, used on ceramic glaze and the influence of its related chemical components, heavy calcined zinc oxide is obtained after high-temperature processing and calcination. Calcined zinc oxide is an important ceramic chemical flux raw material, especially in building ceramic wall and floor tile glaze and low-temperature ceramic glaze and ceramic color. It is also widely used in artistic ceramic glaze. Function and use of calcined zinc oxide in glaze: calcined zinc oxide has a strong melting effect in the glaze, which can reduce the expansion coefficient of the glaze, improve the thermal stability of the product, increase the luster and whiteness of the glaze, and improve the elasticity of the glaze. It can increase the luster of glaze while expanding the melting range. However, it should be used with caution in black glaze containing chromium. Generally speaking, calcined zinc oxide is mainly used in the following aspects: 1、 As a flux: when calcined zinc oxide is used as a flux in low-temperature frit glaze, the general dosage is between 5% and 10%, and that in low-temperature raw glaze is about 5%. 2、 Use as opacifier: add zinc oxide to the glaze with high content of Al  O , which can improve the opacification of the glaze. Because calcined zinc oxide can form zinc spinel crystals with Al ? O ?. In the zinc-containing opaque glaze, Al  O  can improve the whiteness and opacity of the glaze. SiO2 can improve the gloss of glaze. 3、 Used as crystallization agent: In the crystal glaze of art glaze, calcined zinc oxide is an indispensable crystallization agent. When the molten glaze is cooled rapidly, it forms a large crystal pattern, which is very beautiful. The amount of calcined zinc oxide in crystalline glaze is up to 20~30%. 4、 Used to make cobalt azure glaze: calcined zinc oxide is a very important flux in cobalt azure glaze, which can make cobalt oxide form a beautiful azure in the glaze. 5、 As a ceramic pigment: because of its strong melting effect, calcined zinc oxide can be used as a flux, mineralizer and glaze color carrier for ceramic pigments. As the main raw material in the brown ceramic color series 6、 Used as glass additive: the transparency of zinc oxide added with aluminum, gallium and nitrogen reaches 90%, which can be used as glass coating to make visible light pass through and reflect infrared rays. The coating can be applied inside or outside the window glass to achieve the effect of heat preservation or insulation. The most important point of calcined zinc oxide is its antibacterial effect on ceramic surface glaze: calcined zinc oxide is an electronic structure of semiconductor catalyst. Under light irradiation, when a photon with a certain energy or a photon with more than the semiconductor band gap energy Eg shoots into the semi-conductor, an electron is excited from the valence band NB to the conduction band CB, leaving a hole. The excited conduction band electrons and valence band holes can recombine to eliminate the input energy and heat, the electrons are captured in the surface state of the material, the valence electrons jump to the conduction band, and the valence band holes snatch the hydroxyl electrons in the surrounding environment to turn the hydroxyl into free radicals, which can be used as a strong oxidant to complete the degradation of organic matter (or chlorine) and kill bacteria and viruses. Introduction to RA95 Active Zinc Oxide Single Product for Glaze RA95 active zinc oxide was originally a nano-level zinc oxide new material developed by the Hunan headquarters of Xinrunfeng and the United States (Kennedy Space Center) and applied in the aerospace field. It is one of the few oxide-type semiconductor materials that can realize quantum size effect. On the basis of this aviation material, the doctoral research and development team of the ceramic business department of Guangdong Xinrunfeng Zinc Industry Co., Ltd. has, after more than one year, jointly with non-ferrous metal colleges and universities to set up the industry-university-research scientific and technological innovation material project, developed and invented the RA95 glaze active grain zinc oxide that can be applied to ceramic glaze, And the modification on the nanolattice - the lattice displacement coated with ammonium zinc and then filled with silicate nano-active agent at high temperature changed the high temperature molecular motion performance of the sub-nanometer crystal. The innovative active zinc oxide material for glaze has obtained an invention patent. Active zinc oxide for RA95 glaze has both the dual characteristics of nano material and traditional zinc oxide. Compared with traditional zinc oxide products, its particle size distribution range is more suitable for ceramic glaze, with high chemical activity and low harmful impurities. According to the characteristics of fast firing and high temperature melting of ceramic glaze, active zinc oxide for RA95 glaze can rapidly reduce the high temperature viscosity of the glaze at high temperature, and keep the glaze with good transparency, high gloss and hardness; At the same time, the modification on the nanolattice makes the product have photochemical effect and better UV shielding performance, and its UV shielding rate is up to 98%; At the same time, it is also a kind of low-lead and low-cadmium zinc oxide with sanitation and health level, and has a series of unique properties such as antibacterial, anti-odor and anti-enzyme. In addition to being able to 1:1 replace the conventional 99~99.5 calcined zinc oxide in ceramic glaze and adding special functions, it is also widely used in the preparation of high-efficiency photocatalyst, special ceramics, wear-resistant rubber, anti-static plastic, conductive materials, lightning rod parts, photocatalyst, etc.