Abstract
Metal-free imidazolium-based ionic liquid (IL) Brønsted acids 1-methyl imidazolium hydrogen sulphate [HMIM]HSO
4
and 1-methyl benzimidazolium hydrogen sulphate [HMBIM]HSO
4
were synthesized. Their physicochemical properties were investigated using spectroscopic and thermal techniques, including UV-Vis, FT-IR,
1
H NMR,
13
C-NMR, mass spectrometry, and TGA. The ILs were immobilized on mesoporous silica gel and characterized by FT-IR spectroscopy, scanning electron microscopy, Brunauer–Emmett–Teller analysis, ammonia temperature-programmed desorption, and thermogravimetric analysis. [HMIM]HSO
4
@silica and [HMBIM]HSO
4
@silica have been successfully applied as promising replacements for conventional catalysts for alkane isomerization reactions at room temperature. Isomerization of
n
-heptane and
n
-octane was achieved with both catalysts. In addition to promoting the isomerization of
n
-heptane and
n
-octane (a quintessential reaction for petroleum refineries), these immobilized catalysts are non-hazardous and save energy.
Metal-free imidazolium-based ionic liquid (IL) Brønsted acids 1-methyl imidazolium hydrogen sulphate [HMIM]HSO
4
and 1-methyl benzimidazolium hydrogen sulphate [HMBIM]HSO
4
were synthesized.