Ion exchange separation process is the method of using exchanger and ion to exchange and separate. It is a kind of solid-liquid separation method. It’s widely used in water treatment, medicine, metallurgy, chemical industry and other field. The most important categories in ion exchanger are the ion exchange resin, the ion exchange membrane and so on. Ion exchange resin is divided into acidic ion exchange resin, alkaline ion exchange resin and neutral ion exchange resin.
Tungsten is one of China's productive elements. With the progress of science and technology, tungsten smelting technology also has made great progress. In the purification, removing impurity and transformation of crude sodium tungstate solution, domestic scholars pioneered the strongly basic anion exchange technology, but this method consumes large amounts of water and energy. It also pollutes environment and make great loss of tungsten. So increasing sodium tungstate solution concentration and reducing the dilution water consumption is the problem to be solved.
In order to solve this problem, this paper introduces a kind of new technology of ion exchange in high concentration of sodium tungstate solution. Operation method: make the sodium tungstate material liquid at a certain speed flow through ion exchange column and use cinchonine to inspect tungsten leakage point in the liquid. Use 3mol/L NH3 and 5mol/L NH4Clto desorb tungsten in resin. Use sodium thiocyanate spectrophotometric colorimetry to analyze the speed of WO3 in the solution.
According to this method we can get the following conclusions:
1. Adaptive ability of the traditional process to solution concentration is very poor. The new process has excellent adaptability to high concentration of sodium tungstate solution.
2. In the new process, the solution velocity change does not affect the work exchange capacity. The velocity limitation of the solution broadens greatly. This means high production capacity and efficiency.
3. The traditional process requires NaOH concentration less than 8 g/L in the operation, and new technology adsorption process isn’t affected by alkali concentration in the solution.
In a word, compared with the traditional process, new process keeps advantages, and also breaks through the restrictions on liquid concentration. The adsorption, purification and transformation of tungsten can be realized under the condition of highWO3 NaOH concentration. Dilution water has been cut. Floor space and the power consumption in corresponding workshop also have fallen. The processing capacity of equipment relatively increases. Finally the chemical raw material consumption and environmental pollution has been lowered. It benefits the clean and efficient production of tungsten hydrometallurgy.