Sodium sulfide manufacturing methods and applications

sodium sulfide manufacturer

Sodium sulfide manufacturing methods and applications

Sodium sulfide production methods:

Sodium sulfide (Na2S) is a yellow to red solid material soluble in water, slightly soluble in alcohol. It is a strong reducing agent and reacts with oxidant.

No commercial process for the production of sodium sulfide containing neither water nor iron is known. The commercially available sodium sulfide is in every case produced by reduction of sodium sulfate, usually by means of carbon, but also by means of hydrogen and other reducing gases. Reduction with carbon yields a crude melt, which contains, in addition to sodium sulfide, considerable amounts of impurities and by-products such as unreacted carbon, ash constituents, impurities from the carbon, carbonates, sulphites, sodium thiosulfates, and iron compounds. This crude melt is usually extracted with water so that the water-soluble part of the impurities and considerable amounts of iron pass into the extraction liquor. Other reactions take place subsequently in the aqueous solution, and these lead to undesirable by-products. by evaporating the extraction liquor, either crystals of the composition Na S.9H O are obtained or with further evaporation, a product containing 60% of Na S solidifies from the melt. Both hydrates, namely the hydrate crystallising from the solution and containing 32% of Na S, contain considerable amounts of soda, sulfite, thiosulfate, sulfate, and iron salts. The commercially available substance containing 60% Na is colored a dark reddish brown by the iron and can scarcely be used for certain purposes such treatment of textiles. It is not technically or economically possible to reduce the residual 40% of water content by further evaporation on account of the extraordinarily steep rise in the melt temperature above 60% of Na-S and since a suitable material for use in making the necessary apparatus which is resistant to concentrated sodium sulphite melt is unknown. Even evaporation to only 60% of Na S necessitates the use of apparafus made from expensive special alloys or causes heavy wear on other materials.

A process has now been discovered for obtaining a sodium sulphide of excellent purity by reduction of sodium sulphate with carbon or other reducing agents, which sulphide is in particular free from iron and water. The process is based on the fact that anhydrous sodium sulphide, unlike the hydrate, dissolves readily in alcohols.

Claim1: In a process for the production of pure anhydrous sodium sulfide free from iron, the step which comprises heating the melt obtained by reduction of sodium sulfate with carbon and which contains impurities resulting from the reduction process, with an alcohol, filtering the sodium sulfide solution thereby formed and recovering the sodium sulfide from the said solution by evaporating the alcohol.

 

It is known that sodium hydroxide may be reacted with H2S to form Na2S which may be treated with more H2S to convert Na2S to NaHS, and it has been proposed to make sodium hydrosulfide by gassing an Na2S-NaHS liquor with pure hydrogen sulfide.

In processes of the type to which the invention relates, the source of sodium is commercial caustic soda which contains appreciable quantities of impurities, such as iron, copper, nickel, manganese and silicon. These impurities do not discolor caustic soda to any great extent, and hence their presence in commercial caustic is unobjectionable. However, during H2S gassing of commercial caustic liquor, such impurities pass thru the process and are carried into the resulting NaHS liquor. Such impurities may be present in the NaHS liquor as soluble salts or suspended in finely divided condition. While probably largely sulfides, exact compositions of the impurities are not known, and whatever their nature, these subtances are referred to herein as metallic impurities. The presence of even small amounts of these impurities in Na2S or NaHS solutions results in products of very poor appearance because of the highly colored nature of the impurities after having been subjected to H2S gassing. Accordingly, a major problem presented in manufacture of relatively pure sodium hydrosulfide has been the elimination of such impurities.

Commercially available hydrogen sulfide gases contain appreciable amounts of carbon dioxide as an impurity.

Claim2: the method for producing purified sodium sulfide from a sodium hydrosulfide liquor containing (a) at least one metallic impurity of the group consisting of iron, copper, nickel, manganese, and silicon, and (b) an amount of available carbonate of sodium equivalent to more than 0.06% by weight of CO3 radical, which method comprises treating said liquor with an alkaline earth compound so as to react with available carbonate of sodium to precipitate combined CO3 thereof as alkaline earth carbonate, the amount of said alkaline earth compound being at least sufficient to reduce the available carbonate of sodium content of said liquor to an amount equivalent to not more than 0.06% by weight of CO3 radical, controlling the composition of the resulting liquor so that such liquor contains not more than 5% by weight of sodium sulfide, thereby effecting coagulation and precipitation of metallic impurities, and separating said metallic impurities from such liquor.

 

Claim3: The method for producing purified sodium sulfide from a sodium hydrosulfide liquor containing (a) metallic impurities of the type present in commercial sodium hydroxide, and (b) an amount of available carbonate of sodium equivalent to more than 0.06% by weight of COA radical, which method comprises treating said liquor with an alkaline earth compound so as to react with available carbonate of sodium to precipitate combined Cos thereof as alkaline earth carbonate, the amount of said alkaline earth compound being at least sufficient to reduce the available carbonate of sodium content of said liquor to an amount equivalent to not more than 0.06% by weight of Cos radical, controlling the composition of the resulting liquor so that such liquor contains not more than 5% by weight of sodium sulfide, thereby, effecting coagulation and precipitation of metallic impurities, and separating said metallic impurities from such liquor.

 

Sodium sulfide applications:

Sodium sulfide is one of the main chemicals and raw materials in so many industries such as mining industry, leather industry, metallurgy industry, textile industry, dyes and intermediates, pulp and paper, soda ash manufacturing, metal refining industry.

 

Sources:

http://www.freepatentsonline.com

https://patents.google.com

Related products:

Sodium sulphide flakes 60%

 

 

© 2018 Tejaras Co. All Rights Reserved


How can Tejaras Co. help foreign customers to purchase and import Iran origin chemicals and petrochemical products in the new era of imposed U.S. shipping banking and economical sanctions against Iran?

How can Tejaras Co. help foreign customers to purchase and import Iran origin chemicals and petrochemical products in the new era of imposed U.S. shipping banking and economical sanctions against Iran?

 

With respect to be located in one of the most strategic regions in the world, having good access to major commercial ports, railway stations and land roads in the world, high quality of the manufactured chemical raw materials and petrochemical products, and competitive prices which can beat so many other manufacturers in the world, there are thousands of big and medium importers around the world especially in India, East Africa, South Asia, Europe and South America which are willing to buy chemicals and petrochemical products from Iran, but they have worries that how can they purchase from Iran? and how can they receive their purchased products in a safe and smooth way?

 

The fact is that all the companies in the field of leather, textile, mining industries, metallurgy, agriculture, fertilizer manufacturing, chemical manufacturing, refinery, oil and gas, food production, metal refining, alumina refining, lubricant manufacturing, detergent manufacturing, cosmetics manufacturing, construction, water treatment, candle and match manufacturing, paint and dyes manufacturing can benefit from high quality Iran origin chemical raw materials with competitive prices, but how?

 

The first barrier for the customers is banking transactions: almost all the major banks in the world refuse to do transactions with Iranian banks due to U.S. sanctions. Besides, almost none of Iranian manufacturers have any offshore company or bank account. In the best way, they will introduce a foreign bank account from a company which is not directly linked with their own factory in Iran. Therefore, the customers worry that what happens to their money in case any dispute or mismanagement happens with the factory? How can they follow up in case the factory does not cooperate with them in an amicable manner?

How can Tejaras Co. solve banking issues for its valued customers?

With real and exact study of the political and economical situation in the region, we decided to establish strong business partnership with some companies in Dubai, Turkey and Hong Kong, and arrange all our banking transactions and documentation through our these partner companies outside Iran. Therefore, we are pleased to inform you that we can receive payments in EUR/USD/AED in the mentioned countries without any single problem.

Besides, it has been many years we are active in this market, and as we have strong business relationship with our factories, such problems have never happened for our company. But, as we also have legal local contracts with all our Iranian factories and we pay them through official account in Iranian local banks, all the payments to the factories can be followed up legally in Iran through us, and in case any problem or dispute happens with the factory, it can be followed up through Iran Judiciary organization and Chamber of Commerce by our professional legal experts. Therefore, we guarantee that your payments will be 100% safe with us.

 

 

The second barrier for the customers is delivery term: almost all Iranian chemical and petrochemical manufacturers and refineries sell their products on EXW factory basis in bulk, and it is very difficult for foreign customers to make their shipments out of Iran as it is almost impossible for them to communicate with local transportation and packaging/drumming companies in Iran.

How can Tejaras Co. solve delivery issues for its valued customers?

As per our strong business relationships, contracts and partnerships with the leading transportation companies both locally and internationally, we are pleased to inform you that we can deliver all your orders in any region in the world by vessel, train or truck through the fastest smoothest and most cost-effective routes.

We also have the ability to design and print customized packaging for our strong customers upon solo partnership contracts.

 

 

The third barrier for the customers is shipping documents: As per the new sanctions against Iran, in some countries, shipments departed from Iranian ports are not allowed to be cleared at customs. So, the customers may look for some solutions that how they can import Iran origin products to their countries.

How can Tejaras Co. solve shipping documents issues?

As per our cooperation with Iranian shipping line company, we have the ability to ship all cargoes from Iran to Jebel Ali port of U.AE., and then dispatch to the final destination port with economical rates. Needless to say that, no Iranian port name will be mentioned on the shipping documents and bill of lading, and port of loading will be Jebel Ali, U.A.E.

 

Tejaras Co. manufactures, supplies and exports so many strategic chemical products such as caustic soda flakes, sodium sulphide flakes, white oil, low aromatic white spirit, paraffin wax, sulfur, LABSA, glycols, amines, calcium hypochlorite, hydrogen peroxide, methanol, and gasoil.

We are honored to inform you that can be your loyal partner in Iran in order to fulfill all your chemicals and raw materials requirements, so that a dream of smooth business with Iran can come true for your esteemed company.

 

For further information, you can mail us at [email protected]

 

 

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