Active magnesium oxide, also known as light-burned magnesium oxide or caustic magnesium oxide, is magnesium oxide formed by calcining magnesium compounds below 900°C. The chemical activity of magnesium oxide can be expressed by the iodine absorption value (adsorption performance index). The greater the chemical activity, the greater the iodine absorption value, and the lighter it is. When the iodine absorption value is 120-180 mg/g, it is called high-activity magnesium oxide, when the iodine absorption value is 50-80 mg/g, it is called medium-activity magnesium oxide, and when the iodine absorption value is 19-43 mg/g, it is called low-activity magnesium oxide.
Active magnesium oxide is generally relative to heavy magnesium oxide. Since the activity of solid substances is proportional to their surface area, some people use the size of their surface area to express activity, so the specific surface area (the surface area per unit mass of substance) is introduced to regard the specific volume (ml/g) as the reciprocal of the bulk density. Generally speaking, highly active magnesium oxide is in the form of ultrafine powder, which refers to particles with a particle size of 10-1000nm. Due to the extremely small particle size of ultrafine particles, they often show special properties that conventional materials do not have in terms of magnetism, electricity, sound, heat and sensitivity. Therefore, it is widely used as a new type of material. The activity expressed by the citric acid activity value is 12-25. The smaller the value, the higher the activity. The activity expressed by the iodine absorption value is 80-120 (mgI/100gMgO), the specific surface area is between 5-20, and the apparent specific volume is between 6-8.5ml/g. Due to its large specific surface area, it has extremely high chemical activity and physical adsorption capacity, has good sintering performance, does not require the use of sintering aids to achieve low-temperature sintering, and is a preparation of high-functional fine inorganic materials.
With the development of science and technology and the national economy, the application of active magnesium oxide will become more and more extensive, and the demand will further increase. High-activity lightweight magnesium oxide is made of soluble magnesium salts and dolomite as raw materials and finely processed by advanced technology. The product has fine particle size, good dispersion compatibility, and high iodine absorption value. High activity, stable quality, and good performance. It is widely used in chloroprene rubber, fluororubber, butyl rubber, chlorinated polyethylene (CPE), polyvinyl chloride (PVC) plastics and adhesives, advanced inks, paints, etc. It is used in rubber-sheathed cables, mining cables, marine cables and other industries to improve the corrosion resistance, acid resistance, high temperature resistance and other properties of cables, and improve the working stability under harsh conditions.
Active magnesium oxide can also be used as a defluorination adsorbent in water. At present, rural drinking water has water quality problems such as high fluoride, high arsenic, bitter and salty, untreated Class IV and Class IV super surface water, especially excessive fluoride in water, which can seriously cause fluoride poisoning and greatly endanger people’s health. The adsorption effect of activated magnesium oxide can be used to remove fluoride from water and solve water safety.