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.

Methodology (Proposed)

  • 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).

DOE Schematic of post-combustion carbon capture in power plants.

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.