Group-type MS analysis

The group-type MS analysis shows that the extent and/or pattern of aliphatic substitution affects the ease of deoxygenation. For example, Table V presents the weight percentages of ... 

Here, the mixture analytical FIA-MS-MS approach reached its limitation to identify compounds. Hence, LC separations prior to MS analysis are essential to separate compounds with the same m/z ratio but with different structures. The behaviour in the LC separation will be influenced by characteristic parameters of the surfactant such as linear or strongly branched alkyl chain, the type, the number and the mixture of glycolether groups—PEG and/or PPG—and the ethoxylate chains. The retardation on SPE materials applied for extraction and/or concentration also depends on these properties and can therefore be used for an appropriate pre-separation of non-ionic surfactants in complex environmental samples as well as in industrial blends and household detergent formulations. A sequential selective elution from SPE cartridges using solvents or their mixtures can improve this preseparation and saves time in the later LC separation [22],... 

As seen in Table II, the four asphaltene-acid fractions exhibit different volatilities. However, the MS data in Tables V-VII and the IR data reveal no significant differences in the group types present in the volatiles from these four fractions. Consequently, the production of four acid fractions represents the use of an inadequate quantity of A-29 resin in the asphaltene separation rather than a separation based upon compound type. Therefore, the individual asphaltene-acid fractions could have been combined prior to analysis. 

Like other pyrolysis oil processes. Biocarbons Corporation s reactor produces a large number of oil compounds. For mixed hardwood (maple, birch and beech) pyrolyzed at typical operating conditions, 69 peaks were found by GC/MS analysis. Of these, the 14 peaks present at above 2 mole percent, represented 45 mole percent of the product that came through the GC. The 27 peaks between 1 and 2 mole percent, represented an additional 37 mole percent of the product. These compounds that were identified are listed in Table 1, in order of appearance (time). Several of the 4-position groups could also be occurring at the 3 position. All are reactable to make a phenol-forma Idehvde type adhesive. Pyrolysis oil from pine that was nude at the same operating condition (but has not yet been tested for adhesive use) had essentially the same compounds present at >1 mole percent, but at different relative concentrations. Some lower concentration compounds such as fatty acids are only produced from pine, but these compounds are specific to softwoods and the composition of softwoods. A comparison between the mixed hardwoods and pine products is shown in Table 2. 

The type of analysis utilized to determine the composition of a pyrolysate is important because only a certain group of compounds can be seen in one type of analysis. The identification of more volatile compounds found in cellulose pyrolysate can be done very conveniently by on-line Py-GC/MS analysis. The TIC traces of cellulose pyrolysate obtained at 590° C and separated on a Carbowax or on a methyl-phenyl silicone type column were already given in Section 5.2 (Figures 5.2,10, 5.2.11 and 5.2.13). As indicated in Section 5.2, in these chromatograms compounds such as formaldehyde, methanol, or CO were not seen because the mass spectrometer used for the analysis had the mass range detection with a low cut-off at m/z = 32. 

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