Abstract
Under the perspective of potential technical off-gas recovery and recycling, a series of ionic liquids (ILs)
was compared and screened for their applicability as environmentally benign solvents for absorbing sulfur
dioxide (SO2). New molten salts based on imidazolium cations, combined with the 2-formylbenzenesulfonate
anion were developed and identified as unique, regenerative scrubbing agents for SO2. In particular,
the room temperature ILs 1-butyl-3-methylimidazolium 2-formylbenzenesulfonate (BMIM OFBS) and
1-allyl-3-methylimidazolium 2-formylbenzenesulfonate (AMIM OFBS) were compared to already known
SO2-absorbing systems. In their entirety of required properties for absorb-ing and desorbing SO2, the newly
introduced systems are superior to all IL-based scrubbing media described so far: These innovative taskspecific
ILs exhibit low hygroscopicity, good recyclability and, most notably, a remarkable selectivity between
the sour gases SO2 and CO2, even in the state of ambient moisture saturation. As such, the compounds are
providing a high application potential for pressure or temperature swing absorption cycles. The presented
primary results substantiate the advantage of the sheer number of compositional possibilities in developing
ionic liquids for special purposes.
was compared and screened for their applicability as environmentally benign solvents for absorbing sulfur
dioxide (SO2). New molten salts based on imidazolium cations, combined with the 2-formylbenzenesulfonate
anion were developed and identified as unique, regenerative scrubbing agents for SO2. In particular,
the room temperature ILs 1-butyl-3-methylimidazolium 2-formylbenzenesulfonate (BMIM OFBS) and
1-allyl-3-methylimidazolium 2-formylbenzenesulfonate (AMIM OFBS) were compared to already known
SO2-absorbing systems. In their entirety of required properties for absorb-ing and desorbing SO2, the newly
introduced systems are superior to all IL-based scrubbing media described so far: These innovative taskspecific
ILs exhibit low hygroscopicity, good recyclability and, most notably, a remarkable selectivity between
the sour gases SO2 and CO2, even in the state of ambient moisture saturation. As such, the compounds are
providing a high application potential for pressure or temperature swing absorption cycles. The presented
primary results substantiate the advantage of the sheer number of compositional possibilities in developing
ionic liquids for special purposes.
| Original language | English |
|---|---|
| Pages (from-to) | 30-43 |
| Journal | Lenzinger Berichte |
| Volume | 2013 |
| Issue number | 91 |
| Publication status | Published - 2013 |
| MoE publication type | B1 Non-refereed journal articles |
Keywords
- process gas desulfurization
- waste prevention
- gas absorption
- selective absorption
- sustainable chemistry