New Process for Na₂CO₃ Production from Na₂SO₄ Based on Modeling the Na₂SO₄-(NH₄)₂SO₄-MEA-MEG-H₂O System.

Area of Science:

• Chemical Engineering
• Industrial Chemistry
• Materials Science

Background:

• The conventional Mirabilite-Solvay process (MSP) for soda ash production is energy-intensive.
• There is a need for alternative, more energy-efficient methods for producing soda ash (Na2CO3) from sodium sulfate (Na2SO4).

Purpose of the Study:

• To demonstrate a novel process for producing soda ash from sodium sulfate.
• To develop an energy-efficient alternative to the conventional Mirabilite-Solvay process.

Main Methods:

• Antisolvent crystallization of unreacted sodium sulfate (Na2SO4) from a mixed monoethanolamine (MEA) and monoethylene glycol (MEG) solution.
• Measurement and modeling of Na2SO4 and (NH4)2SO4 solubilities using the electrolyte nonrandom two-liquid (E-NRTL) model.
• Reaction of concentrated Na2SO4 brines with CO2 and NH3 to produce soda ash.

Main Results:

• Successfully demonstrated a new process for soda ash production using sodium sulfate as a feedstock.
• Achieved separation of unreacted Na2SO4 from soluble (NH4)2SO4 via antisolvent crystallization in MEA-MEG solutions.
• Produced anhydrous dense soda ash with a bulk density up to 1146 kg/m3.

Conclusions:

• The developed process offers a viable and energy-efficient alternative for soda ash production from sodium sulfate.
• Antisolvent crystallization in MEA-MEG solutions is effective for separating key components.
• The process yields high-density anhydrous soda ash.