Holdup and regime transition in reciprocating and rotating sieve plate column (RRSPC) for C6(mim)PF6 ionic liquid –water system

Abstract

ABSTRACT In the present study, Reciprocating and Rotating Sieve Plate Column (RRSPC) was used with C6(mim)PF6; ionic liquid as dispersed phase and water as continuous phase to study hydrodynamics, which has not been studied till date. Experiments were conducted at different RPM, reciprocating pulsating frequency (RPF), dispersed phase velocity and total throughput, at different O/A ratios. It was found that disperse phase holdup increases with increase in dispersed phase velocity, total throughput (at different O/A ratios) and with increase in RPM/RPF. Simultaneous reciprocating pulsation and rotation produce good quality of dispersion of ionic liquid in range of 50 to 65 RPM/RPF. Phase inversion of dispersed phase to continuous phase takes place at 70 RPM/RPF when dispersed phase velocity () exceeds 4.2 mm/s. Higher holdup was observed at lower RPM/RPF in RRSPC as compared to other type of column reported in literature. The optimum operating condition for RRSPC was found to be, 60–65 RPM/RPF to achieve better holdup and uniform quality of dispersion. It turned to emulsion phase above 70 RPM/RPF. Snapshots show flow visualization as well as dispersion quality. Regime maps of the system were presented to understand the mixing settler regime, dispersion and emulsion regime ranges.