TY - JOUR
T1 - Thermogravimetric, infrared and mass-spectroscopic analysis of the desorption of methanol, propan-1-ol, propan-2-ol and 2-methylpropan- 2-ol from montmorillonite
AU - Breen, C.
AU - Flynn, J. J.
AU - Parkes, G. M.B.
PY - 1993/3
Y1 - 1993/3
N2 - The desorption of methanol (MeOH), propan-1-ol (n-PrOH), propan-2-ol (i-PrOH) and 2-methylpropan-2-ol (t-BuOH) from Na+-, Ca2+-, Al3+-, Cr3+- and Fe3+-exchanged montmorillonite has been studied using variable temperature
infrared (IR) spectroscopy and thermogravimetric analysis (TGA).
Alcohol-saturated trivalent cation (M3+) exchanged samples exhibit
maxima in the derivative thermograms at 20 and 110°C (MeOH), 30 and 160°C (n-PrOH), 20 and 110°C (i-PrOH) and 20, 55 and 80°C (t-BuOH). Alcohol-saturated Na+ and Ca2+-exchanged montmorillonite samples exhibit maxima at higher temperatures
in the i-PrOH (20 and 140°C) and t-BuOH (30, 90 and 110°C) desorption profiles but at the same temperatures
for MeOH and n-PrOH. Mass spectroscopic
analysis of the vapours desorbed from the alcohol-treated samples show that the
low-temperature maxima in the alcohol desorption from the M3+-exchanged clays are due to unchanged alcohol, whilst those occurring at
80°C (t-BuOH), 110°C (i-PrOH) and 160°C (n-PrOH) are due, in the main,
to alkene produced from the intramolecular dehydration of the respective
alcohol. Changes in the IR spectra of the adsorbed alcohols occur at temperatures
which are in accord with the mass spectral data. No mass spectral evidence was
found for the formation of dialkylethers via the competing intermolecular
process but dimerisation and oligomerisation of t-BuOH were observed.
AB - The desorption of methanol (MeOH), propan-1-ol (n-PrOH), propan-2-ol (i-PrOH) and 2-methylpropan-2-ol (t-BuOH) from Na+-, Ca2+-, Al3+-, Cr3+- and Fe3+-exchanged montmorillonite has been studied using variable temperature
infrared (IR) spectroscopy and thermogravimetric analysis (TGA).
Alcohol-saturated trivalent cation (M3+) exchanged samples exhibit
maxima in the derivative thermograms at 20 and 110°C (MeOH), 30 and 160°C (n-PrOH), 20 and 110°C (i-PrOH) and 20, 55 and 80°C (t-BuOH). Alcohol-saturated Na+ and Ca2+-exchanged montmorillonite samples exhibit maxima at higher temperatures
in the i-PrOH (20 and 140°C) and t-BuOH (30, 90 and 110°C) desorption profiles but at the same temperatures
for MeOH and n-PrOH. Mass spectroscopic
analysis of the vapours desorbed from the alcohol-treated samples show that the
low-temperature maxima in the alcohol desorption from the M3+-exchanged clays are due to unchanged alcohol, whilst those occurring at
80°C (t-BuOH), 110°C (i-PrOH) and 160°C (n-PrOH) are due, in the main,
to alkene produced from the intramolecular dehydration of the respective
alcohol. Changes in the IR spectra of the adsorbed alcohols occur at temperatures
which are in accord with the mass spectral data. No mass spectral evidence was
found for the formation of dialkylethers via the competing intermolecular
process but dimerisation and oligomerisation of t-BuOH were observed.
UR - http://www.scopus.com/inward/record.url?scp=0027510855&partnerID=8YFLogxK
U2 - 10.1180/claymin.1993.028.1.11
DO - 10.1180/claymin.1993.028.1.11
M3 - Article
AN - SCOPUS:0027510855
VL - 28
SP - 123
EP - 137
JO - Clay Minerals
JF - Clay Minerals
SN - 0009-8558
IS - 1
ER -