Ionic Liquid-Modified Amine Sorbent for Low-Temperature CO2 Regeneration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional CO2 capture processes using aqueous amine solutions face issues such as aging, degradation, high regeneration energy requirements, and thermal susceptibility, leading to inefficiencies and environmental concerns like amine emissions and foaming.
Innovation Solution
Development of CO2 capture sorbents comprising a solid support with CO2-sorbing amine and ionic liquid, which enhances CO2 sorption and desorption characteristics, allowing for regeneration at lower temperatures and maintaining high selectivity and capacity through catalytic action.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If conventional aqueous amine solutions are used for CO2 capture, then CO2 absorption capacity is achieved, but high regeneration energy and thermal degradation occur
Solution Approach 1:
The patent changes the physical state parameter of the amine from liquid (aqueous solution) to solid (supported amine), which fundamentally alters the regeneration conditions. Solid supported amines enable low-temperature regeneration (<100°C) compared to high-temperature requirements for aqueous solutions, directly reducing regeneration energy while improving thermal stability
Solution Approach 2:
The patent creates a composite material system consisting of amine functional groups supported on solid substrates (such as silica, alumina, or polymeric supports). This composite structure combines the CO2 reactivity of amines with the thermal stability and mechanical strength of solid supports, resolving the contradiction between absorption capacity and thermal stability
2Productivity
If aqueous amine solutions are used in packed columns, then large gas/liquid interfacial area is achieved for CO2 removal, but liquid entrainment and foaming occur
Solution Approach 1:
The patent transitions from liquid-gas contacting (aqueous amine solutions in packed columns) to solid-gas contacting (supported amine sorbents in fluidized beds). This pneumatic approach allows gas to flow through or over solid particles, achieving high mass transfer efficiency without liquid entrainment or foaming issues inherent in liquid-based systems
Solution Approach 2:
The patent replaces the mechanical liquid circulation system (pumps, packed columns, tray columns) with a solid particle-based system that can be regenerated by simple heating or pressure swing. This substitution eliminates the mechanical complexity and harmful liquid entrainment while maintaining high CO2 removal efficiency
3Temperature
If solid sorbents with amine are developed, then regeneration temperature is reduced, but desorption rate becomes too low for commercial applications
Solution Approach 1:
The patent employs porous solid supports (such as mesoporous silica, alumina, or polymeric porous materials) with controlled pore size and surface area. The porous structure provides high surface area for amine loading, enhances CO2 diffusion to active sites, and facilitates rapid desorption by providing multiple exit pathways, thereby achieving both low regeneration temperature and high desorption rate
Solution Approach 2:
The patent modifies the local environment of the amine functional groups by supporting them on specific substrates with tailored surface properties, pore structures, and basicity. This local optimization of the amine microenvironment enhances both the sorption capacity and the desorption kinetics, enabling low-temperature regeneration with high desorption rates suitable for commercial applications
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The sorbents achieve efficient CO2 capture with reduced regeneration temperatures, lower energy consumption, and minimized amine emissions, improving the overall efficiency and environmental sustainability of CO2 capture processes.
Implementation Method 1
ionic liquid thereon... maintaining high selectivity and capacity through catalytic action
Implementation Method 2
CO2-sorbing amine... efficient CO2 capture
Implementation Method 3
regeneration at lower temperatures... reduced regeneration temperatures
Data Source
AI summary
A sorbent useful for CO2 capture is described, including a solid support with CO2-sorbing amine and ionic liquid thereon. The ionic liquid is catalytically effective to enhance sorbent characteristics such as (i) CO2 sorption capacity, (ii) CO2 sorption rate, (iii) CO2 desorption capacity, (iv) CO2 desorption rate, and (v) regeneration temperature, in relation to a corresponding sorbent lacking the ionic liquid. In specific implementations, the sorbent is regenerable at temperatures significantly below 100° C., thereby avoiding the need for steam heat desorption and enabling utilization of waste heat or other low energy thermal regeneration sources.