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Soda Ash bags 2019


What is Soda Ash?

Commonly named “Soda”, the Soda Ash is known as Sodium carbonate, Na2CO3. Its CAS registry number is 497-19-8 and its Harmonized System (HS) code is 283 620.

Sodium Carbonate or Natural Soda Ash (based on Trona) are present in a wide range of applications. They are already well-known for their effectiveness in flux for glass and flux for silicate. Moreover, they are also playing another role: a chemical that can substitute caustic soda and increase PH.


In which consumer markets is Soda Solvay® usually present?

  • Glass Industry – Raw material for melting and flux agent to reduce the melting point of silica (and consequently reduces energy consumption) 
  • Detergents – Alkaline support, grease removal (saponification effect), water softening
  • Chemical Industry – Acting as a strong base (increases pH) with a softer effect compared to caustic soda
  • Metallurgical processes – Desulfurization of pig iron, flux agent for mineral extraction, production of Lithium Carbonate …  
  • Pulp & Paper - Can substitute caustic soda
  • Supplement in pharma – High purity carbonate IPH is used as an Active Pharmaceutical Ingredient (API) to enable tabletting  (effervescent tablets)


Solvay is available in two different grades

Soda Solvay® is available in dense and light grades to meet its customers’ specifications in accordance with all applicable safety, health and environmental standards.

The dense grade has a bulk density of ~1 t per m3 and a Particle-Median-Diameter (D50) of 300 to 500 microns.  

Soda Ash Dense is the grade preferred for glass manufacture because its granular properties make it widely dust-free and reduce the risks of segregation during transport and handling.

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The light grade has a bulk density of ~0,5 t per m3. The D50 of approximately 100 microns is very well suited for detergent and chemical applications.

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A pharmaceutical grade of sodium carbonate anhydrous is also available. It is produced in a dedicated production facility in Dombasle (France).

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Why do we speak about the “Solvay process”?

We speak about the “Solvay process” because in the 1860s, Ernest Solvay invented a new soda ash process using ammonia as processing agent - enabling CO2 to substitute Chlorine at the Sodium atom (also called "ammonia process"). This process replaced the previous Leblanc process as Solvay process is much less impactful for the environment.  We still use today this process to produce synthetic soda ash. The other synthetic route is the Hou process developed in China where ammonia is not recycled but sold as a byproduct: ammonium chloride.

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