Kinetics of Tetra-n-Butylammonium Bromide + Hydrogen Semi-Clathrate Hydrate Formation

Engineering Sciences and Fundamentals
2011 AIChE Annual Meeting
AIChE Annual Meeting
October 16, 2011 - 8:00pm

Hydrogen (H2) is regarded as a promising alternative to fossil fuels, because it offers a solution for three main global challenges: (i) reduction of greenhouse gas emissions, (ii) fulfillment of energy requirements, and (iii) reduction of local air pollution. However, due to the difficulty in finding an effective storage medium, the application of H2,for example in the automotive sector, is currently limited.

Single H2 clathrate hydrates have been considered as potential future H2 storage material. Their profitability, safety, fast and high reversibility and efficient production make them more suitable for this application than other H2 storage materials. However the main disadvantage of single H2 clathrate hydrates is the high pressure (200 MPa at 273K) required for formation. Recently, it has been reported that tetra-n-butyl ammonium bromide (TBAB) can be used as an additive to form H2-TBAB semi-clathrate hydrates with water, which are stable at much more practical conditions (atmospheric pressure and close to room temperature). Similar to clathrate hydrates, semi-clathrate hydrates have empty small cavities that can be filled by H2 molecules. Moreover, the TBAB molecule is non-volatile which means there is no contamination of the H2 released. These favorable conditions make the H2-TBAB semi-clathrate hydrates particularly attractive as a potential H2 storage media.

In order to elucidate the potential of H2-TBAB semi-clathrate hydrates for H2 storage, kinetic data and in situ Raman spectroscopy measurements were obtained for two TBAB concentrations (2.56 mol% and 3.7 mol% in the liquid solution) in a pressure range of 5 – 16 MPa. In order to prove or disapprove the stochastic nature of hydrate growth, two approaches were applied: (i) isochoric temperature cycle method and (ii) temperature constant method. To the best of our knowledge, these are the first results of time-dependent kinetic conditions of H2-TBAB semi-clathrate hydrates using in situ Raman spectroscopy in an aqueous solution. Results will be presented at the conference.

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.
Presenter(s): 

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.

Pricing

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 $15.00 Buy now