Removal of pyridine from dilute aqueous streams using hollow fiber supported liquid membranes

Abstract

The removal of pyridine from aqueous phase using hollow fiber supported liquid membranes has been investigated. Effect of several parameters such as feed concentration, extractant concentration, type of extractants, etc. has been studied. Organic solvents such as, 2-nonyl phenol (2-NP), 4-nonyl phenol (4-NP), stearic acid (SA), and di-(2-ethylhexyl) phosphoric acid (D2EHPA) were used as extractants. It was observed that the initial flux of pyridine increased with an increase in extractant concentration. The investigations showed that phenolic-based extractants (4-NP or 2-NP) were better for pyridine removal as compared to other extractants. The equilibrium experiments have been carried out by varying stirring speed and time in order to find the reaction kinetics and equilibrium time. Mass transfer-based model was used to explain the removal of pyridine for three different modules. Scale-up experiment shows nearly similar flux values of pyridine at both the scales. The model results were found to be in good agreement with the experimental observations. The results have been explained on the basis of steric effects, acidity of the extractant molecules along with the overall mass transfer resistance for the transport of pyridine.

Keywords:

• Pyridine
• Supported liquid membranes
• Flux
• Separation
• Mass transfer
• Model

Acknowledgment

The authors are grateful to the Department of Science and Technology (DST), Government of India, for providing financial assistance to research work through DST project (DST No.: SR/S3/CE/048/2012).