Quantifying Liquid-Solid Mass Transfer in a Trickle Bed Using T<inf>2</inf>- T<inf>2</inf> Relaxation Exchange NMR

Acknowledgements: The authors thank Shell Global Solutions International B.V. for funding supporting this work. SVE thanks the Sir Winston Churchill Society of Edmonton and the Natural Sciences and Engineering Research Council of Canada for additional financial support. QZ thanks the IChemE Andrew Fellowship for additional financial support. For the purpose of open access, the authors have applied a Creative Commons Attribution (CC BY) licence to any Author Accepted Manuscript version arising from this submission.Funder: Shell Global Solutions International; doi: http://dx.doi.org/10.13039/100016773Funder: Sir Winston Churchill Society of EdmontonFunder: IChemE Andrew FellowshipAbstractMeasurement of the liquid-solid mass transfer coefficient within a trickle bed (i.e. gas-liquid flow within a packed bed) of porous silica pellets is achieved through the use of $${T}_{2}-{T}_{2}$$ T 2 - T 2 relaxation exchange nuclear magnetic resonance (NMR). Compared to many conventional measurement techniques, the NMR method enables measurement of mass transport using pellets of real commercial interest. Mass transfer coefficients measured using the NMR technique over a range of liquid Reynolds number, 0.2 $$\le R{e}_{\mathrm{L}}\le $$ ≤ R e L ≤ 1.4, are compared to a number of literature correlations, with values measured using the NMR method falling within the range predicted by the correlations. The results demonstrate the importance of considering both the flow conditions and the type of pellets used to develop mass transport correlations in trickle beds. This novel NMR application may be utilized in the future to screen catalyst pellets in trickle beds for optimal mass transport properties.