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Updated: Jul 12, 2026
10:19
A CO2 Concentration Gradient Facility for Testing CO2 Enrichment and Soil Effects on Grassland Ecosystem Function
Published on: November 21, 2015
Advanced buffer materials for indoor air CO2 control in commercial buildings
P E Rajan1,2, A Krishnamurthy1, G Morrison2
1Department of Chemical & Biochemical Engineering, Missouri University of Science and Technology, Rolla, MO, USA.
Indoor Air
|April 6, 2017
Summary
Solid sorbents, particularly silica supported amines like tetraethylenepentamine (TEPA), effectively remove indoor carbon dioxide (CO2). These materials can be regenerated by airflow, offering a passive method for controlling CO2 levels in buildings.
Area of Science:
- Environmental Science
- Materials Science
- Chemical Engineering
Background:
- Indoor air quality is a growing concern, particularly in buildings with fluctuating occupancy.
- Elevated carbon dioxide (CO2) levels can negatively impact cognitive function and necessitate energy-intensive ventilation.
Purpose of the Study:
- To evaluate solid sorbents for passive control of indoor CO2 concentrations.
- To investigate silica-supported amines, specifically those using tetraethylenepentamine (TEPA), poly(ethyleneimine) (PEI), and 3-aminopropyltriethoxysilane (APS), for CO2 removal.
Main Methods:
- Synthesis of amine-loaded silica sorbents with varying amine concentrations.
- Characterization using thermogravimetric analysis (TGA).
- Evaluation of CO2 adsorption and desorption using equilibrium and dynamic flow-through chamber experiments at different scales and humidity levels.
Main Results:
- TEPA-impregnated silica demonstrated high CO2 adsorption capacity at ppm levels and efficient desorption via airflow.
- In a 10 L chamber, TEPA-based sorbents reduced CO2 by up to 5% and desorbed 93% of adsorbed CO2 within 16 hours.
- In an 8 m3 chamber, 18 g of sorbent removed approximately 8% of injected CO2.
Conclusions:
- Silica-supported amines, especially TEPA, are promising for passive CO2 control in buildings.
- This technology has the potential to reduce ventilation energy requirements and improve indoor air quality.
- Further extrapolation suggests significant CO2 reduction achievable in real-world building applications.
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