Titanium dioxide (TiO2) has stable physical and chemical properties, excellent optical and electrical properties, and excellent pigment performance. TiO2 is the most versatile white pigment with the best application effect. This article will share the production process of titanium dioxide pigment.
2 kinds of titanium dioxide production processes
Tio2 production chloride process
The chloride process is considered to be the development trend of today’s titanium dioxide preparation technology, and its manufacturing process is divided into 3 stages: chlorination, oxidation and After-processing stages.
First of all, high-purity coke must be mixed with ore, and form a chemical reaction with chlorine under the action of high temperature to produce titanium chloride (coarse TiCl4) containing more impurities. Then use chemical treatment agent or distillation method to remove various ions of crude TiCl4, so that titanium tetrachloride becomes more pure and transformed into refined titanium tetrachloride.
TIPS: After going through the chlorination section, refined TiCl4 is finally obtained, and a certain amount of oxidation is required to finally obtain the corresponding titanium dioxide.
Add the refined TiCl4, oxygen and nucleating agent and other reactants into the reactor together, then adjust and increase the working environment temperature, and finally quench it to 700 °C through low-temperature circulating chlorine gas Next, use the pipeline to cool to 200 °C. At this time, there will be a certain amount of titanium dioxide in the chlorine gas. The titanium dioxide is separated and collected through dechlorination treatment to enter the post-treatment section.
After TiCl4 is oxidized in the gas phase, the coarse TiO2 should be further processed. After dechlorination, the surface and ball milling should be continued to be processed and polished.
Chloride process characteristics
The chloride process can effectively shorten the production time of titanium dioxide, and the production efficiency of its products is high, and the control ability is strong. The control method of the chloride process is automatic control, which does not produce pollutants and can effectively reduce environmental pollution. The quality of this type of titanium dioxide has strong stability, and its impurities are less. Therefore, the production of titanium dioxide products by the chloride process can effectively reduce the production cost and promote the economic benefits of the industry.
tio2 production sulfate process
The raw material of the sulfuric acid process is acid-soluble titanium slag or ferro-titanium. The process flow is: sulfuric acid decomposes titanium ore into TiOSO4. After purification and concentration, the titanium solution is hydrolyzed into TiO2•H2O. The hydrolyzed product is washed, filtered, and calcined before surface treatment, and separation and impurity removal work should be carried out in a timely manner. Then a complete titanium dioxide product is obtained.
There are 3 kinds of titanium dioxide that will use sulfuric acid process: titanium dioxide products, anatase titanium dioxide and rutile titanium dioxide.
The production process is mainly divided into acid hydrolysis, leaching, hydrolysis and calcination stages.
Sulfuric process characteristics
The raw material used in the process is acid-soluble titanium slag or ferro-titanium, which is not only easy to obtain but also low in price, so the production cost is not high.
The sulfuric process is relatively mature, and the equipment used is simple, with strong reproducibility.
The disadvantage of the sulfuric process is that it takes a long time to produce. Due to the large consumption of water and sulfuric, more by-products and waste will be derived, which will cause environmental pollution.
In addition to the chlorination process and the sulfuric process for preparing titanium dioxide, the titanium dioxide preparation process also includes a mixing process, a phosphoric acid process, and a nitric acid process. At present, the processes for industrial preparation of titanium dioxide are mainly sulfuric process and chlorination process. Other processes are unable to achieve industrial production due to serious equipment corrosion, many by-products and difficult to handle, high pollution from the three wastes, and high energy consumption.
With the continuous improvement of technical level, the titanium dioxide industry is developing rapidly, and the requirements for products are more perfect. Technicians need to vigorously develop the production technology of titanium process, increase the research and development of related products, and continue to integrate the production and application of titanium dioxide. Method, boldly innovate in practice, and strive to achieve a breakthrough in titanium dioxide production technology as soon as possible.