Reducing energy requirements and enhancing MEA-CO₂ desorption rates in amine solutions with KIT-6 nanostructures

The primary challenge hindering the widespread industrial adoption of amine-based CO₂ capture technology is the sluggish desorption rate of carbon dioxide (CO₂) and the substantial energy required in the regeneration phase. Despite considerable advancements aimed at reducing energy demands through novel amine solvents and process optimization, there remains a critical need for innovative solutions. This study introduces mesoporous silica nanoparticles KIT-6, along with super solid acid catalysts SO₄²⁻/SnO₂ and SO₄²⁻/ZrO₂, to assess their impact on enhancing the desorption rate and reducing the energy consumption in the CO₂ capture process from rich monoethanolamine (MEA) at 96 °C. Our findings indicate that all the tested catalysts significantly expedite the regeneration process, reducing the energy required for regeneration up to 33.50 % and boosting the desorption rate by 150.25 % beyond what is achieved with MEA alone. KIT-6, in particular, displayed superior catalytic activity and energy efficiency in the desorption process. The catalysts SO₄²⁻/ZrO₂, SO₄²⁻/SnO₂, and KIT-6 improved the desorption rate by 20 %, 37.5 %, and 150.25 %, respectively, and cut down the energy required for regeneration by 11.10 %, 24.44 %, and 33.50 % respectively when compared to conventional aqueous MEA under the same conditions. Moreover, KIT-6 was subjected to ten cycles of CO₂ desorption testing to verify the cyclic robustness. A potential mechanism explaining the enhanced CO₂ capture facilitated by KIT-6 is also proposed within this work.