United Conversion Process Coupling CO₂ Mineralization with Thermochemical Hydrogen Production.

Area of Science:

• Chemical Engineering
• Sustainable Energy
• Environmental Science

Background:

• Conventional CO2 mineralization is energy-intensive and economically unviable.
• Thermochemical cycles for hydrogen production face challenges in energy efficiency.
• There is a need for integrated solutions for carbon capture and clean energy generation.

Purpose of the Study:

• To propose a united conversion process coupling CO2 mineralization with thermochemical hydrogen production.
• To address the challenges of high energy consumption and low economic value in CO2 mineralization.
• To investigate the energy economy and CO2 conversion capacity of the integrated system.

Main Methods:

• Utilized natural magnesium silicate minerals for CO2 fixation into carbonate minerals.
• Employed a thermochemical cycle to dissociate H2O for hydrogen production.
• Conducted hydrolyzation and carbonation experiments in a homemade reactor and developed a system simulation.

Main Results:

• Achieved an optimal MgI2 hydrolyzation rate of 75% without alkali consumption.
• The integrated system demonstrated an optimal energy conversion efficiency of 47.6%.
• The modified net energy requirement for CO2 mineralization was found to be 1.4 MJ/kg CO2.

Conclusions:

• The proposed integrated process offers a new solution for clean energy production and carbon emission reduction.
• The system exhibits superior energy conversion efficiency compared to conventional sulfur-iodine thermochemical cycles.
• The method presents a competitive and economically viable approach for CO2 mineralization.