Wet process production technology for sodium pyrosulfite

Abstract

The invention provides a wet production process of sodium pyrosulfite, which is characterized in that the operation process is as follows: 1) preparation of sulfur dioxide: burning sulfur to make sulfur dioxide, which is cooled and washed for later use; 2) preparation of sodium sulfite solution: using Low-content sodium sulfite preparation solution; 3) Preparation of sodium pyrosulfite crystals: add sulfur dioxide to the solution prepared in step 2), and precipitate sodium pyrosulfite crystals; 4) Preparation of sodium pyrosulfite: Centrifuge the sodium pyrosulfite crystals, and recycle the sodium sulfite solution , and dry the sodium metabisulfite crystals. Through the preparation method provided by the present invention, low-content sodium sulfite is directly used to produce sodium pyrosulfite, which greatly shortens the process flow, makes the wet production process of sodium pyrosulfite save the waste of raw material resources, realizes effective production, increases enterprise income, and is more applicable In the current industrialized large-scale production and processing.

Description

technical field [0001] The invention relates to the field of sodium sulfite, in particular to a wet production process of sodium pyrosulfite. Background technique [0002] Sodium sulfite is common sulfite, monoclinic crystal or powder. It is irritating to eyes, skin and mucous membranes, and can pollute water sources. Decomposition by high heat produces toxic sulfide fumes. [0003] Sodium pyrosulfite is white or yellow crystalline powder or small crystals with a strong smell of sulfur dioxide. Sodium pyrosulfite has a wide range of biological uses in industry. It can be used in the purification of chloroform, coagulant, deoxidizer, mordant, in pharmaceutical technology, rubber preparation Food grade sodium metabisulfite can be used as leavening agent and preservative in various aspects of life. [0004] In the traditional production and processing method of sodium metabisulfite, two methods of dry method and wet method are adopted. At the same time of dry method producti...

AI Technical Summary

Problems solved by technology

[0004] In the traditional production and processing method of sodium metabisulfite, two methods of dry method and wet method are adopted. At the same time of dry method production and processing, soda ash and water are mixed according to a certain ratio, and then sulfur dioxide gas is introduced to make the reaction to prepare the finished product, but The finished product prepared by dry method contains many impurities and the purity is not high, so it cannot be further popularized and applied when some production needs

For the wet preparation process, often due to a large amount of energy consumption, the production cost is greatly increased, and the purity of the preparation is low, and it cannot be used as a further application