Assessing Anhydrous Tertiary Alkanolamines for Gas Purifications

Innovations of Green Process Engineering for Sustainable Energy and Environment
AIChE Annual Meeting
October 30, 2012 - 1:45pm-2:10pm
Assessing Anhydrous Tertiary Alkanolamines for Gas Purifications


Paul M. Mathias, Kash Afshar, Satish Reddy, Arnold R. Smith, Rubin J. McDougal
Louis V. Jasperson, Phillip K. Koech, Mark D. Bearden, Charles J. Freeman, David J. Heldebrant

Anhydrous tertiary alkanolamines chemically react with CO2 and H2S, with greater selectivity for the latter. This is in direct contrast to aqueous amine-based solvent systems with higher selectivity for CO2 due to stronger chemical fixation than for H2S. Anhydrous tertiary alkanolamines exhibit pressure-induced chemical fixation of CO2 to form zwitterionic ammonium alkylcarbonate ionic liquids, while the same tertiary alkanolamines react with H2S at atmospheric pressures to form hydrosulfide ionic liquids. This difference in capture pressure implies that anhydrous alkanolamines could be chemically selective for H2S over CO2 under specific conditions.  We present here the first vapor-liquid equilibrium (VLE) data of anhydrous ethyldiethanolamine (EDEA) with CH4, C3H8, H2S and CO2 at 10 and 50 °C measured by the PTx and PTxy methods. The data are modeled in Aspen Plus® using an electrolyte NRTL model. Data trends and phenomena are discussed for each gas.  We also compare anhydrous EDEA’s simulated performance for CO2 and H2S separations to other solvents such as Fluor Solvent, Econosolv, and aqueous methyldiethanolamine (MDEA) for representative gas-processing applications.

Professional Development Hours
0.5 PDHs
You will be able to download and print a certificate for these PDH credits once the content has been viewed. If you have already viewed this content, please click here to login.

Would you like to access this content?

No problem. You just have to complete the following steps.

You have completed 0 of 2 steps.

  1. Log in

    You must be logged in to view this content. Log in now.

  2. Purchase Technical Presentation

    You must purchase this technical presentation using one of the options below.
    If you already purchased this content recently, please click here to refresh the system's record of ownerships.


Credits 0.5 Use credits
List Price $25.00 Buy now
AIChE Members $15.00 Buy now
AIChE Undergraduate Student Members Free Free access
AIChE Graduate Student Members Free Free access
Related Topics: 
Skill Level: