Residence time distribution study in a pilot-scale liquid phase catalytic exchange (LPCE) column packed with a mixture of hydrophobic and hydrophilic catalysts

Sunil Goswami; Niranjan S Shenoy; Krunal A Mistry; Sulabh Gupta; Vijay K Sharma; K Bhanja; Harish J Pant

doi:10.1016/j.apradiso.2021.109840

Residence time distribution study in a pilot-scale liquid phase catalytic exchange (LPCE) column packed with a mixture of hydrophobic and hydrophilic catalysts

Appl Radiat Isot. 2021 Oct:176:109840. doi: 10.1016/j.apradiso.2021.109840. Epub 2021 Jun 29.

Authors

Sunil Goswami¹, Niranjan S Shenoy², Krunal A Mistry², Sulabh Gupta², Vijay K Sharma¹, K Bhanja², Harish J Pant³

Affiliations

¹ Isotope and Radiation Application Division, Bhabha Atomic Research Centre, Mumbai, 400085, India.
² Heavy Water Division, Bhabha Atomic Research Centre, Mumbai, 400085, India.
³ Isotope and Radiation Application Division, Bhabha Atomic Research Centre, Mumbai, 400085, India. Electronic address: hjpant@barc.gov.in.

PMID: 34256272
DOI: 10.1016/j.apradiso.2021.109840

Abstract

Residence time distribution (RTD) measurements were carried out in a packed bed column designed for exchange of hydrogen isotopes. The main objective of the study was to characterize the liquid phase mixing under various processes and operating conditions. The packed bed was composed of a mixture of two different types of catalytic packing materials, i.e., a hydrophobic material and a hydrophilic material. Technitium-99m (^99mTc) as sodium pertechnetate was used as a radiotracer for RTD measurements. From the measured RTD curves, mean residence times (MRTs), liquid holdup and degree of mixing of liquid phase were evaluated. An axial dispersion model exchange with stagnant zones was used to simulate the measured RTD curves. The results of model simulation showed that volume fraction of hydrophobic to hydrophilic packing and gas/liquid superficial velocities affect the liquid holdup, bed pressure drop and liquid phase dispersion/mixing characteristics. The results of the present study will help to screen packing, optimize the volume of the packing fractions, design and construct the catalyst and optimize the operating conditions for scale up of the isotope exchange process.

Keywords: Axial dispersion exchange with stagnant zone; Catalytic exchange column; Holdup; Hydrophilic; Hydrophobic; Mean residence time.