Acidolysis process in titanium dioxide production process

Abstract

The invention discloses an acidolysis process in a titanium dioxide production process. The acidolysis process comprises the following steps of: directly mixing rough ilmenite concentrate with 10-60% sulfuric acid in mass percentage so as to obtain rough ilmenite concentrate sulfuric acid paste, controlling the mass percentage of the rough ilmenite concentrate to be 10-70%, subsequently wet-milling by using a ball mill till the residue of a sieve of which the particle size is 325 meshes is less than 30% so as to obtain the qualified rough ilmenite concentrate sulfuric acid paste for acidolysis, directly injecting the rough ilmenite concentrate sulfuric acid paste into acidolysis equipment, adding 98% concentrated sulfuric acid to initialize main reaction, subsequently curing, leaching and reducing so as to obtain an acidolysis titaniferous solution. The process can be carried out by using an ordinary ball mill, is simple in acidolysis ore grinding system, small in one-time investment, lower in maintenance cost and low in operation cost; the rough ilmenite concentrate is directly used for acidolysis, so that a great deal of flying mineral dust is prevented, and the yield of the ilmenite concentrate is increased; the process is relatively lower in requirement on the moisture of the rough ilmenite concentrate, thereby being conductive to lowering the transportation and storage cost of the rough ilmenite concentrate; and the acidolysis process is simple in process, easy to operate and applicable to large-scale production and popularization.

Description

technical field [0001] The invention relates to a production process of titanium dioxide, in particular to an acid hydrolysis process for production of titanium dioxide. Background technique [0002] Titanium dioxide is one of the most important inorganic pigments and chemical raw materials. Pigment grade titanium dioxide is mainly used in coatings, papermaking, plastics, rubber, latex paint, printing ink, chemical fiber and other industries. Non-pigment grade titanium dioxide is mainly used in enamel, capacitors, welding electrodes, etc. [0003] The production methods of titanium dioxide are generally divided into sulfuric acid method and chloride method. Among them, the sulfuric acid method is a common traditional production method, and its steps generally include: acidolysis reaction of titanium concentrate and concentrated sulfuric acid to produce titanyl sulfate, precipitation, crystallization, hydrolysis to generate metatitanic acid, and metatitanic acid is washed ,...

AI Technical Summary

Problems solved by technology

However, there are certain deficiencies in this system: 1. The noise of the ball mill during the grinding of ore powder is large, which has a great impact on the operator's body; 2. The grading system requires that the titanium concentrate must run at a certain speed, so it must be equipped with a high-power fan, and the system consumes more energy. Higher; 3. The high-hardness titanium concentrate running directly in the grinding system at high speed will cause serious system wear, and at the same time, the system material requirements are high, which directly leads to an increase in system maintenance costs; 4. Titanium concentrate production, transportation and storage process It is unavoidable to get damp in the medium, but the traditional grinding system uses wind as the material delivery medium, so the humidity requirement for the coarse titanium concentrate is high, and the moisture content of the coarse titanium concentrate should not exceed 3%, otherwise the grinding system will be blocked and the grinding system will not be able to 6. The grinding system equipment is complicated, the one-time investment is large, and the maintenance cost is high

[0007] In summary, both the traditional acid hydrolysis process and the current improved acid hydrolysis process for sulfuric acid titanium dioxide production have the following disadvantages: 1. The crude titanium concentrate grinding system is complicated, and the one-time investment and maintenance costs are high; 2. The two acid hydrolysis processes The grinding system has extremely high requirements on the moisture content of the coarse titanium concentrate, and has extremely high requirements on the moisture resistance during the long-distance transportation and storage of the coarse titanium concentrate; The pot is often very dusty, causing environmental pollution and yield reduction; 4. Long-term practice shows that there is scaling in the premixing tank in the two acidolysis premixing processes, and it is difficult to clean

At present, there is no actual report to overcome the above-mentioned shortcomings by a new acid hydrolysis process.

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