1. Comprehensive utilization of waste and secondary resources
At present, the main raw materials for the production of iron oxide red pigments by wet process are almost all iron sheets. As the output of iron oxide pigments increases, iron sheet resources will inevitably be scarce, which will lead to an increase in production costs and a decline in corporate profits. Therefore, manufacturers must develop and utilize new synthetic raw materials to meet production needs.
2. Iron mud in chemical plant
Many organic chemical factories and pharmaceutical factories use iron powder to reduce organic compounds. The oxidized iron powder is commonly called iron mud and can only be used for waste disposal. The basic composition of iron mud is ferroferric oxide, which has the same chemical composition as iron black, but its physical properties still cannot meet the requirements of pigments. If it can be further processed, it can be used as iron black. The principle is to use iron powder to reduce nitrobenzene, nitrobenzene is reduced to aniline, and iron powder is oxidized to iron oxide pigments, using different operating conditions to obtain a series of iron-based pigments of various brands.
3. Superfine iron oxide
The synthetic iron oxide is crushed to micron or even nanometer level with ultrafine grinding equipment, which is called ultrafine iron oxide. The ultra-fine iron oxide pigment can improve its tinting strength, is easy to disperse, has high gloss, and can prevent sinking, floating, and blooming in the application system. Therefore, ultrafine iron oxide has good application prospects. However, due to the extremely fine particles of the ultrafine iron oxide pigment, the surface has a lot of positive charges, and it is easy to agglomerate into agglomerates, resulting in a decrease in application performance. Therefore, the superfine iron oxide pigment must be surface modified to improve its dispersibility and compatibility in the base material. This has important theoretical and application value for improving the quality and performance of the product and increasing its added value. . Zheng Shuilin et al. studied the surface modification of ultrafine iron oxide red pigments, analyzed the mechanism of surface modifiers and additives and iron oxide, and proposed a better modified formula for ultrafine iron oxide red pigments.
4. Heat-resistant iron oxide
Generally, iron oxide yellow and iron black start to be dehydrated or oxidized and become discolored at 177°C because they contain crystal water. Therefore, it cannot be used in plastics and baking coatings that require processing at higher temperatures. After the nucleation treatment, it can improve its heat resistance, and can be used in polypropylene, automobile repair paint, various color pastes and high gloss latex paints.
