SGS Sodium Sulfite Anhydrous, Sodium Sulphite Use For Dechlorinating Agent

                                        ANHYDROUS SODIUM SULFITE/SODIUM SULPHITE                               FOR WATER TREATMENT 
 

Descriptive chemistry

Sodium sulfite is decomposed by even weak acids, giving up sulfur dioxide gas.
Na2SO3 + 2 H+ → 2 Na+ + H2O + SO2
A saturated aqueous solution has pH of ~9. Solutions exposed to air are eventually oxidized to sodium sulfate. If sodium sulfite is allowed to crystallize from aqueous solution at room temperature or below, it does so as a heptahydrate. The heptahydrate crystals effloresce in warm dry air. Heptahydrate crystals also oxidize in air to form the sulfate. The anhydrous form is much more stable against oxidation by air.

Applications

Sodium sulfite is primarily used in the pulp and paper industry. It is used in water treatment as an oxygen scavenger agent, to treat water being fed to steam boilers to avoid corrosion problems,[2] in the photographic industry to protect developer solutions from oxidation and (as hypo clear solution) to wash fixer (sodium thiosulfate) from film and photo-paper emulsions, in the textile industry as a bleaching, desulfurizing and dechlorinating agent and in the leather trade for the sulfitization of tanning extracts. It is used in the purification of TNT for military use. It is used in chemical manufacturing as a sulfonation and sulfomethylation agent. It is used in the production of sodium thiosulfate. It is used in other applications, including froth flotation of ores, oil recovery, food preservatives, and making dyes.
SODIUM SULFITE is a white odorless powder. Density 2.633 g / cm3. Moderately toxic. Sinks in water and dissolves slowly. Also transported as a heptahydrate Na2SO3.7H2O.

Reactions

Sodium sulfite forms a bisulfite adduct with aldehydes, and with ketones forms a sulfonic acid. It is used to purify or isolate aldehydes and ketones.
Sodium sulfite (sodium sulphite) is a soluble sodium salt of sulfurous acid (sulfite) with the chemical formula Na2SO3. It is a product of sulfur dioxide scrubbing, a part of the flue-gas desulfurization process. It is also used as a preservative to prevent dried fruit from discoloring, and for preserving meats, and is used in the same way as sodium thiosulfate to convert elemental halogens to their respective hydrohalic acids, in photographyand for reducing chlorine levels in pools.
Sodium Sulfite is a white crystal or powder with reducing property. Sodium sulfite exhibits bleaching, de-sulfurizing, and dechlorinating activities. This agent was used by food industry to help maintain the fresh appearance of food products. It is also a component in many drugs, which helps maintain their potency and stability. FDA has ruled sodium sulfite a new animal drug of low regulatory priority.
 

 
The difference between 96% and 97% anhydrous sodium sulfite
Author: KIM. Date: January 24, 2018
Since entering the chemical industry, many friends and customers come to ask me, what is the difference between 96 and 97 % of anhydrous sodium sulfite, only just one percent difference, why the price has so big differnce? At first, I didn't understand like normal people. I just told the customers that I would ask our colleagues in the technology and production department before I could reply. I am not not smart, there is no other way, on this professional question, now, slowly by slowly, I know a little anhydrous sodium sulfite difference , but did not calm down to sum up these contents and details. Today, I can finally make a good summary and share with you.
First of all, a simple science popularization, what is anhydrous sodium sulfite?
Anhydrous sodium sulfite also be called sodium sulfite, is an industrial chemical salt, sodium salt, belonging to the basic general chemical products, white crystalline powder, the appearance is similar to our edible salt, as follows:

 
Sodium sulfite is widely used, so there are many manufacturers in China and a great demand in the world.
For example, it can be used as a catalyst for the addition reaction of urea-formaldehyde resin synthesis. As a reductant, it can protect oxygen-sensitive materials. It is also used as antioxidant, antioxidant and neutralizer. Used as film developer, chemical industry as reducing agent and sulfonating agent, dechlorinating agent and bleaching agent in printing and dyeing industry, stabilizer of chemical fiber, of course, the most important food additive as preservative, bleaching agent and so on.
Many instructions about the use of sodium sulfite are simply copied from others'opinions on the internet, so you can see that the version is almost the same. This simple version really can not fully explain the wide use and important role of this basic industrial salt, so I specially summarized an article on the use of sodium sulfite for your reference. The links are as follows:
The contents of anhydrous sodium sulfite are as follows:
 

 
DIFFERENCE BETWEEN 96% AND 97% PURITY SODIUM SULFITE:

 
 
In short, the lower content of anhydrous sodium sulfite, the higher impurity , the darker color, the lower the content with bad smell, while high purity sodium sulfit almost no smell. On the contrary, the higher content of anhydrous sodium sulfite, the lower impurities, and the whiter or even colorless transparent.
Diffrent puirty sodium sulfite photos, from 70% -97% PURITY :