Factors affecting bubble size in ionic liquids

Abstract

This study reports on understanding the formation of bubbles in ionic liquids (ILs), with a view to utilising ILs more efficiently in gas capture processes. In particular, the impact of the IL structure on the bubble sizes obtained has been determined in order to obtain design principles for the ionic liquids utilised. 11 ILs were used in this study with a range of physico-chemical properties in order to determine parametrically the impact on bubble size due to the liquid properties and chemical moieties present. The results suggest the bubble size observed is dictated by the strength of interaction between the cation and anion of the IL and, therefore, the mass transport within the system. This bubble size - ILs structure-physical property relationship has been illustrated using a series of QSPR correlations. A predictive model based only on the sigma profiles of the anions and cations has been developed which shows the best correlation without the need to incorporate the physico-chemical properties of the liquids. Depending on the IL, selected mean bubble sizes observed were between 56.1 and 766.9 μm demonstrating that microbubbles can be produced in the IL allowing the potential for enhanced mass transport and absorption kinetics in these systems.

Polarized emission from light-emitting electrochemical cells using uniaxially oriented polymer thin films of poly(9,9-dioctylfluorene-co-bithiophene)

“…This IL-dependent emission zone may be due to the size of the cation; the relatively large P 44412 cation cannot penetrate into the neat F8T2 films efficiently, while the small BMP cation can penetrate and thus the n-doped region is formed. The sizes of these cations have not been reported so far, but it was reported that the free volume of BMP-TFSA is 35.36 cm 3 =mol, which is approximately four times smaller than that of tetradecyltrihexylphosphonium bis(trifluoromethylsulfonyl)amide (P 66614 -TFSA) (140.25 cm 3 =mol), 19) the cation size of which is slightly larger than that of P 44412 -TFSA. Although more careful and systematic studies are required to understand what determines the position of the emission zone, the results indicate the importance of electrolyte species in making the emission zone far away from the metal contact, which is important for avoiding optical absorption loss by metals.…”

Nanocapillary confinement of imidazolium based ionic liquids

“…Surface nanobubbles have been reported in viscous media, 44 but in ionic liquids there have so far only been optical measurements proving micron sized and larger bubbles. 45 Another possibility for the large variance in the resistance versus diameter is that nanocapillaries have by themselves an ill defined geometry due to the production method, and that small variations of the tapering angle are not controllable. In order to increase any ordering effects platinum coated nanocapillaries were also used (analogously to ref.…”

Ultrasound‐mediated therapies for the treatment of biofilms in chronic wounds: a review of present knowledge

“…Therefore, gas diffuses from the smaller bubbles to the larger ones, leading to dissolution and disappearance of the smaller bubbles. It is well documented that factors such as shell composition, fabrication method used, the relative chemical environment and temperature can substantially influence MB size and its temporal evolution (Mulvana et al, 2010;Sun et al, 2014;Lee et al, 2015b;Taylor et al, 2017).…”