How to dihydrate process phosphoric acid

To dihydrate process phosphoric acid in the production of refined phosphoric acid and phosphate fertilizer, one of the most important steps is to adjust the concentration of phosphoric acid to 40% - 50%, with a corresponding adjustment in the flow rate. Inorganic precipitation methods are favored for this process because they have few moving parts and can be operated continuously. With conventional batch inorganic precipitation, iron deficiency, due to its weak solubility in water, needs to be solved by adding sodium pyrophosphate as a catalyst.

Uses of phosphoric acid

1. Phosphate fertilizer;

The phosphoric acid used in phosphate fertilizer manufacturing has a high phosphorus content and is soluble in water, which makes it suitable for anionic fermentation; also, it can be easily adjusted to 40 - 50% by adjusting the flow rate. It has good solubility in other liquids such as alcohols, glycerol and vegetable oils; the phosphate content may be further adjusted to the desired level by adding ammonium or magnesium chloride. This is as a results of dihydrate process phosphoric acid.

2. Acidic solution;

Using phosphoric acid as a raw material, with the help of one or two other raw materials mainly inorganic precipitation, it can make an aqueous acidic solution. The pH value should be adjusted strictly to 4.5 - 6 by conducting acidification with sulfuric acid or small quantity of sodium hydroxide. An aqueous system for producing explosive compound such as ammonium nitrate, ammonium phosphate and ammonium sulfate are also made in the same way.

3. Alloying;

Using phosphoric acid as a raw material, with the help of one or more inorganic salts, it is possible to make a new alloy. The product has high strength and good corrosion resistance. This kind of alloy is particularly suitable for metal parts of electronic and chemical machines and instruments.

4. Fluid media;

With the help of phosphoric acid as a raw material, it is possible to make a new fluid medium, which can be used in the special fields such as instrumentation, petroleum and fertilizer industry.

5. Chemical intermediate;

Using phosphoric acid as a raw material to produce acetic-acid-methyl-ester intermediate (it is more commonly called methyl acetate). As with most organic synthesis intermediates, methyl acetate can be used directly or with chemical transformation to obtain other chemical compounds. The production of acetic acid formaldehyde resin is also carried out using methyl acetate.

6. Metal cleaning agent;

Using phosphoric acid as a raw material, it is possible to make a metal cleaning agent. It can clean the surface of metal and other materials with strong corrosion resistance, such as stainless steel, titanium alloy and nickel in the field of chemical industry. The cleaning effect depends on the concentration of phosphoric acid and temperature; if lower than 40% P₂O₅ concentration, it won't get rid of rust completely.

7. Antioxidant;

Using phosphoric acid as a raw material, it is possible to make an antioxidant inorganic salt (such as phosphate zinc). Importantly, it has the ability to inhibit lipid peroxidation.

8. Guaiacol;

Using phosphoric acid as a raw material, it is possible to make a copper-free substance guaiacol with high anti-oxidant and anti-microbial effect, and it has low cost. The choice of using phosphoric acid as a raw material is relevant to the choice of oxidizing agent, which can be used to produce guaiacol by oxidation method. It's believed that the choice of oxidizing agent should be as simple as possible, but also carefully analyzed after considering cost performance and product characteristics.

9. As a source of nitric acid;

Using phosphoric acid as a raw material, it is possible to make an aqueous nitric acid by catalytic decomposition reaction of nitrogen compounds. Decomposition method can be further developed by applying high temperature. The decomposition product of nitrogen compound can be used as a raw material to produce nitric acid; the purchasing cost is relatively lower when it's produced on-site.

10. Research chemicals;

Phosphoric acid can be used as a raw material to produce various research chemicals, such as pharmaceutical products and pesticides. However, it is not easy to do so because of the strict process control and high cost. It is relatively easy to produce new organic chemicals that are used in organic synthesis with phosphoric acid as a raw material.

In conclusion, dihydrate process phosphoric acid is a kind of raw material popular and traded in domestic, international market. It is a kind of raw material with short supply, which has high demand in chemical industry.