Manufacturing method of oxalic acid
Oxalic acid is an important organic chemical raw material, widely used in medicine, chemical industry, metallurgy and other fields. In the field of chemical production raw materials, there are mainly the following manufacturing methods of oxalic acid:
1. Oxidation method
Oxidation method is a commonly used method in the production of oxalic acid, which mainly takes starch, glucose, cellulose and other carbohydrates as raw materials, and then oxidizes them to make oxalic acid. Its specific process flow is as follows:
1. Raw material preparation: add starch, glucose and other raw materials into the reactor.
2. Oxidation reaction: add oxidizing agent, such as nitric acid, hydrogen peroxide, etc., control a certain temperature and pH, so that the raw materials oxidized to produce oxalic acid.
3. Separation and purification: the reaction solution is separated and purified to obtain oxalic acid products.
The advantage of oxidation method is that the process is simple and easy to operate, but the generated oxalic acid has low purity and needs to undergo further purification treatment.
Two, carbonyl synthesis method
Carbonyl synthesis method is a more advanced oxalic acid manufacturing method, mainly with carbon monoxide and sodium hydroxide as raw materials, under the action of catalyst, oxalic acid is produced through carbonylation reaction. The specific process flow is as follows:
1. Raw material preparation: mix carbon monoxide and sodium hydroxide in a certain proportion and add them into the reactor.
2. Carbonylation reaction: Under the action of catalyst, control a certain temperature and pressure to make carbon monoxide and sodium hydroxide undergo carbonylation reaction to produce sodium oxalate.
3. Acidification and crystallization: the solution of sodium oxalate is acidified with an acidifier to produce oxalic acid and crystallize and precipitate.
4. Separation and drying: The crystallized oxalic acid is separated and dried to obtain oxalic acid product.
The advantages of carbonyl synthesis method are high product purity and high yield, but the process conditions are more demanding and need to be carried out under high temperature and high pressure conditions.
Third, ethylene glycol oxidation method
Ethylene glycol oxidation method is a relatively new manufacturing method of oxalic acid, mainly using ethylene glycol as raw material, oxidation reaction to produce oxalic acid. Its specific process is as follows:
1. Raw material preparation: add ethylene glycol into the reactor.
2. Oxidation reaction: add oxidizing agent, such as hydrogen peroxide, etc., and control a certain temperature and pH, so as to oxidize ethylene glycol to generate oxalic acid and carbon dioxide.
3. Separation and purification: the reaction solution is separated and purified to obtain oxalic acid product.
The advantage of the glycol oxidation method is that the raw materials are easy to obtain and the reaction conditions are mild, but the generated oxalic acid has a low purity and needs to undergo further purification treatment.
In summary, there are various manufacturing methods of oxalic acid, and different methods have different advantages and disadvantages and scope of application. When choosing the manufacturing method of oxalic acid, it is necessary to make comprehensive consideration according to the specific production conditions and needs, and choose the most suitable method for yourself. At the same time, it is necessary to pay attention to safety and environmental protection in the production process, comply with relevant laws and regulations and standard requirements to ensure product quality and production safety.
