2-Propanol, temperature-programmed

Figure 8.19 Two-diaenslonal separation of the components of a coal derived gasoline fraction using live switching. Column A was 121 n open tubular column coated with poly(ethelene glycol) and column B a 64 m poly(dimethylsiloxane) thick film column. Both columns were temperature programmed independently taking advantage of the two oven configuration. Peak identification 1 acetone, 2 2-butanone, 3 > benzene, 4 isopropylmethylketone, 5 isoprop-anol, 6 ethanol, 7 toluene, 8 => propionitrile, 9 acetonitrile, 10 isobutanol, 11 — 1-propanol, and 12 = 1-butanol. (Reproduced with permission from Siemens AG).

March [233] modified the method as follows. Esterification was performed in 6 Af HC1 in w-propanol at 150°C for 3.5 min with subsequent acylation at the same temperature for 12 min. Analysis was carried out in a column packed with 2.5% of OV-101 and 0.5% of OV-7 with temperature programming. An improved separation was obtained at the expense of a longer analysis time (up to 55 min), however. 

TMS esters are the derivatives of oxygen-containing anions that have been applied most frequently to GC analysis. They were first applied to the analysis of silicates [582], Further, the method was developed for the analysis of five silicates in siliceous rocks [583], as follows. A 20-g amount of powdered sample was added to a mixture of 125 g of ice, 150 ml of concentrated HC1, 300 ml of 2-propanol and 200 ml of hexamethyl-disilazane, which had been stirred for 1 h. The complete reaction mixture was then stirred for 16 h at room temperature. After filtration the silazane (upper) layer was separated, washed with water, mixed with 2.5 g of Amberlyst 15 for 1 h, filtered and stripped at 115°C. The liquid residue in the distillation flask was analysed on a column packed with SE-30 with temperature programming. 

Fishel, C. T. and Davis, R. J. (1994). Characterization of Mg-Al mixed oxides by temperature-programmed reaction of 2-propanol. Langmuir 10, 159. 

In this paper, we will discuss the use of temperature programmed desorption as a complementary technique for obtaining lattice concentrations for high-silica materials. While TPD of ammonia is commonly used as a measure of the number of acid sites in zeolites, this paper will discuss the use of the reactive probe molecules, 2-propanamine and 2-propanol. It has previously been demonstrated that well-defined adsorption complexes, with a stoichiometry of one molecule/Al atom could be observed in high-silica zeolites for a number of adsorbates. These complexes were found to be independent of Si/Al2 ratio for a series of H-ZSM-5 zeolites and were unaffected by... 

Temperature-Programmed Decomposition of 2-Propanol on the Zinc-Polar, Nonpolar, and Oxygen-Polar Surfaces of Zinc Oxide... 

The dehydrogenation reaction produces acetone and hydrogen, and is dominant over basic oxides ( ) The dehydration reaction produces propene and water, and is dominant over acidic oxides. It would be interesting to see if the competition between these two pathways depend on the exposed crystal planes of ZnO. We report here the results of such an investigation. 2-Propanol was decomposed on ZnO single crystal surfaces by the temperature programmed decomposition technique. To assist the interpretation of data, the temperature programmed desorption of propene and acetone were also studied. 

Gas Chromatography. To verify the compounds identified by HPLC, both standards and product solutions were converted to propyl esters with BF3-propanol according to the method of Salwin and Bond (12). Analysis of the esterified compounds was performed on a Hewlett Packard 5880A gas chromatograph equipped with a flame ionization detector and a bonded Superox FA (Alltech Assoc., Inc. Deerfield, IL) fused-silica capillary column (25m x 0.25mm I.D., 0.2 pm film thickness). The temperature program was 100 C to 240 C at 5 C/min and 10 min at 240 C. The injector temperature was 225 C and the detector temperature was 300 C. Carrier flow rate (He) was 1.0 ml/min. Injection volume was Ipl with a split ratio of 80 1. 

Figure 6.3 Conparlson of the separation of the octylphenol poly(ethylene glycol) ether, Triton X-16S on a packed column, left, and an open tubular column, right, using UV detection. For the packed column separation al0cmx2mmI.D. column packed with Nucleosil C g, d. 3 micrometers, temperature > 170 C, and mobile phase carbon dioxide (2 ml/min] and methanol (0.15 nl/rnin). pressure programmed from 130 to 375 bar in 12 min were used. For the open tubular column separation a 10 m x 50 micrometers I.O., SB-Biphenyl-30, temperature = 175°C, mobile phase carbon dioxide (0.175 ml/min) and 2-propanol (0.0265 ml/min) pressure programmed, 125 bar for 5 min, then ramped from 125 to 380 bar over 19.5 min, and held at 380 bar for 15 min. were used. (Reproduced with permission from ref. 57. Copyright Preston Publications, Inc.) ...

The concentration of products in the supernatants was determined on a Varian model 2400 gas chromatograph equipped with a flcune ionization detector. The chromatograph had installed a 6 ft X 1/8 in stainless steel teflon lined column packed with Chromosorb W-AW coated with 10% AT-1000. The temperature of the column was programmed from 100 C to 180 C at a rate of 20 C/min. Helium was used as the carrier gas at a flow rate of 30 ml/min. The flame ionization detector temperature was 230 C. A 10% (w/w) n-propanol solution containing 4% (w/w) H2SO4 was used as an internal standard. 

The flow rate required for pyrolysis is determined by injecting through the pyrolyser head 1 ul of headspace gas from a retention time standard comprising methanol -n-propanol (50 + 50) with the column temperature at 100°C and immediately programming at 8 C min-1. The flow rate of nitrogen is adjusted to give retention times of 2.6 and 9.1 minutes for methanol and n-propanol respectively. 

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