ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Driving force and activation energy in air-gap membrane distillation process

Joanna Kujawa and Wojciech Kujawski

Faculty of Chemistry, Nicolaus Copernicus University in Toruń, 7 Gagarina st., 87-100 Toruń, Poland

E-mail: kujawski@chem.umk.pl

Abstract: The present study investigated the impact of the driving force (Δp) on the transport properties. All the experiments and calculations were performed for air-gap membrane distillation (AGMD). In the course of the experiments, it was found that an identical value of Δp could be attained by applying different values of feed and permeate temperatures. It was highlighted that constant values of water fluxes could be achieved using the constant driving force created by different temperatures. Moreover, the relation between ln(J_H₂O) and 1/Tf was shown to be linear only for the J_H₂O created at ΔT = T_f - T_p > 35 K. This work’s significant finding was to highlight the limitation of the Arrhenius-type equation applied in the activation energy calculations.

Keywords: activation energy – air-gap membrane distillation – hydrophobic PTFE membrane

Full paper is available at www.springerlink.com.

DOI: 10.1515/chempap-2015-0155

Chemical Papers 69 (11) 1438–1444 (2015)