USDOE – Carbon Capture
Post-Combustion Carbon Capture
The Civil & Environmental Engineering research group along with the Mechanical Engineering research group at Prairie View A&M University performs research on the evaluation of post-combustion carbon capture methods using Polyethylenimine (PEI) functionalized titanate (TiO2) nanotubes.
- Establish a knowledge base on the synthesis of TiO2 nanotubes, adsorption characteristics of PEI, and protocols available for the impregnation of PEI.
- Develop optimized protocols for synthesis of TiO2 nanotubes impregnated with PEI.
- Characterize the PEI impregnated TiO2 nanotubes and use it for refining the parameters for synthesis such as temperature, concentration and time.
- Review literature to study the state of carbon capture technologies, nonmaterial synthesis protocols, reactor designs, and experimental protocols.
- Develop PEI impregnated TiO2 nanotubes.
- Evaluate thermal stability and morphological study of the PEI impregnated TiO2 nanotubes.
- Develop a fully functionalized CFD model that can be used for various reactor parameters and materials properties.
- Change the experimental testing of carbon capture under different conditions of temperature, concentrations, and time periods to determine optimal conditions for carbon capture.
- Identify a fully optimized and validated CFD model along with a standard operating procedure for bench scale carbon capture reactor
Findings, To Date (Based on Review of Literature)
- The current major CO2 capture technologies are oxy-combustion capture, pre-combustion capture, and post-combustion capture.
- Post-combustion carbon capture was found to be especially desirable due to its potential to retrofit existing power plants with reasonable cost.
- A simplified schematic of post-combustion carbon capture for a coal-fired power plant is shown in Figure 1. CO2 is captured after the flue gases are cleaned up by Electro Static Precipitator (ESP) and Flue Gas Desulfurization (FGD).
Figure 1: Schematic of post-combustion carbon capture in power plants.
- The current major post-combustion carbon capture technologies are absorption, adsorption, membrane, and cryogenics.
- Current technologies for post-combustion CO2 capture focus mainly on solvent-based absorption. However, the low pressure of the power plant flue gas would result in additional cost for CO2 compression, transportation and storage.
- Other disadvantages of absorption include degradation in an oxidizing atmosphere, higher energy intensity during regeneration, limited CO2 loading capacity, and corrosion with foaming and fouling characteristics.
- There are limited studies that used PEI impregnated TiO2 nanotubes in post-combustion carbon capture. The high surface areas and specific adsorption sites of porous materials make porous solid adsorbents good candidates for application in CO2 capture.
- Synthesizing highly efficient amines-functionalized nanoporous materials is still a big challenge; more efforts need to be put on the investigation of optimal parameters for synthesizing economic and effective nanomaterial for CO2 capture.