Isopropylation of toluene: a comparative study of microporous zeolites and mesoporous MCM-41 materials

A comparative study on the catalytic activity of Zn and Fe containing Al-MCM-41 molecular sieves on t-butylation of phenol

“…It may be due to the easy availability of free active sites for adsorption namely the carbonyl group of TBA, compared to the sterically crowded alcoholic OH in t-butyl alcohol. Isopropyl acetate has been proved to be a better phenol alkylating agent in our previous study [22].…”

Vapour phase esterification of butyric acid with 1-pentanol over Al-MCM-41 mesoporous molecular sieves

“…The total scans were 150 and the line broadening was 50Hz. 27 Al-MAS-NMR chemical shifts were reported with reference to the liquid solution of aluminium nitrate.…”

“…Solid state 27 Al-MAS-NMR experiments were performed at room temperature on a BRUKER MSL 500 NMR spectrometer with resonance frequency of 104.22 MHz, spinning rate of 8 KHz with a pulse length of 1.0 s, a delay time of 0.2 s and spectral width of 330 ppm. The total scans were 150 and the line broadening was 50Hz.…”

“…The specific BET surface area, average pore diameters (BJH method) and specific pore volume for the calcined materials are presented in table 1. The 27 Al-MAS-NMR spectra of the samples are shown in figure 2. The peak around 53.7 ppm is attributed to the presence of aluminium in tetrahedral coordination [23].…”

“…The requirement of high energy is due to aggregation of 1-pentanol to form alcohol clusters. The long chain alcohol clusters formed around the Bronsted acid sites through H-bonding at lower temperatures [27]. At higher temperatures the decrease in conversion is attributed to coke deposition due to oligomerization of olefin (yellow mass).…”