Development of a Novel Mass Spectrometric ... - Jacobs University

More documents

Recommendations

Info

Results and Discussion Intens. [%] 100 80 60 40 20 0 +MS 449.5 561.6 491.6 243.0 313.3 281.3 341.3 365.4 577.6 603.7 250 300 350 400 450 500 550 600 m/z Figure 3-6 APCI mass spectrum of model mixture of n-alkanes injected using n- pentane Table 3.1 Summary of APCI data of n-alkanes Alkane M ∙+ (M-1) + (M-3) + (M-3) + H 2 O C 12 N Y* N Y C 13 N Y* N Y C 14 N Y* N Y C 15 N Y* N Y C 16 N Y* N Y C 18 N Y* N Y C 20 Y Y N Y C 21 Y Y N Y C 22 Y Y N Y C 23 Y Y* N Y C 24 Y Y N Y C 26 Y* Y N Y* C 28 Y Y N Y* C 32 Y Y Y* Y C 36 Y Y Y* Y C 40 Y Y Y* Y *Species with low Intensity Further direct infusion experiments were performed using standard mixtures of alternative composition such as, C7-C40 and C8-C40, C21-C40 n-alkane standards using n-heptane as the APCI reagent. Such experiments yielded a 41
Results and Discussion common feature regarding the n-alkanes’ detection. Each of these saturated n- alkanes were depicted instantly as (M-1) + molecular species which was accompanied by low intensity M •+ ions. Figure 3-7 shows an APCI-MS spectrum of the C7-C40 standard. This clearly emphasized that each single (M-1) + was strictly related to its corresponding n-alkane precursor within the standard mixture. Although the relative product ion abundances do not exactly match the relative molar concentration of each component in the C7-C40 mixture, they are still remarkably close when considering the fact that the volatilities of the compounds vary widely. Other n-paraffin mixtures were also tested by the same method. Figure 3-8 shows the mass spectrum of n-paraffin mixture containing C18, C20, C22 and C24 detected as m/z 269, m/z 297, m/z 325 and m/z 353 respectively. In all cases the ideal behavior of these analytes is mostly attributed to the proper solvent selection, purity of reference standards and careful tuning of the APCI method settings. In fact ionization was achieved without the use of any additional additives and without any fragmentation. The data demonstrates that molecules of various volatilities (boiling points ranging from 174 °C of C10 to 525 °C of tetracontane) can be efficiently ionised by APCI and accurately mass analysed by TOF MS. Intens. [%] 100 +MS 561.6 547.6 80 533.6 505.6 60 449.5 477.5 40 20 253.3 281.3 337.4 239.3 379.4 407.5 435.5 0 211.2 200 250 300 350 400 450 500 550 m/z Figure 3-7 APCI-MS spectrum in positive ion mode of C7-C40 showing (M-1) + ions of n-alkanes 42
Page 1 and 2:
Development of a Novel Mass Spectro
Page 3 and 4:
Declaration of Authorship I ,Nadim
Page 5 and 6:
This work has been carried out unde
Page 7 and 8: Contents Contents Declaration of Au
Page 9 and 10: List of Figures List of Figures Fig
Page 11 and 12: List of Figures Figure 3-39 MS 2 fr
Page 13 and 14: List of Tables List of Tables Table
Page 15 and 16: Abbreviations Abbreviations APCI AP
Page 17 and 18: Abbreviations UV VGOs VOCs VRs ultr
Page 19 and 20: Introduction Analytical chemistry h
Page 21 and 22: Introduction 1.2 Presence and Fate
Page 23 and 24: Introduction aliphatic hydrocarbons
Page 25 and 26: Introduction Figure 1-1 Examples of
Page 27 and 28: Introduction Figure 1-2 Range of io
Page 29 and 30: Introduction fractions. 42 Another
Page 31 and 32: Introduction 1.3.5 APLI Other crude
Page 33 and 34: Introduction products). Other molec
Page 35 and 36: Introduction Other studies performe
Page 37 and 38: Introduction APLI-FT ICR-MS Crude o
Page 39 and 40: Introduction spectrometry in as muc
Page 41 and 42: Introduction catalytic processing t
Page 43 and 44: Introduction Figure 1-6 Kendrick ma
Page 45 and 46: Introduction including determinatio
Page 47 and 48: Introduction 1.5 Scope and Signific
Page 49 and 50: Experimental e) Other model mixture
Page 51 and 52: Experimental 2.2.2 Preparation of O
Page 53 and 54: Experimental 2.4 Graphical Presenta
Page 55 and 56: Results and Discussion experiment.
Page 57: Results and Discussion Intens. [%]
Page 61 and 62: Results and Discussion 3.2 APCI-TOF
Page 63 and 64: Results and Discussion These compou
Page 65 and 66: Results and Discussion Intens. [%]
Page 67 and 68: Results and Discussion Ions were pr
Page 71 and 72: Results and Discussion procedure ba
Page 75 and 76: Results and Discussion to produce m
Page 77 and 78: Results and Discussion 519.5863 519
Page 79 and 80: Results and Discussion Higher mass
Page 87 and 88: Results and Discussion isolated fro
Page 93 and 94: Results and Discussion 3.4.5 Tandem
Page 97 and 98: Results and Discussion injected int
Page 101 and 102: Results and Discussion 3.4.8 Quanti
Page 103 and 104: Results and Discussion Int. x 10000
Page 105 and 106: Results and Discussion Table 3.6 Qu
Page 107 and 108: Results and Discussion assessment o
Page 109 and 110:
Results and Discussion hydrocarbons
Page 111 and 112:
Results and Discussion Intens. [%]
Page 113 and 114:
Page 115 and 116:
Page 117 and 118:
Results and Discussion of n-alkanes
Page 119 and 120:
Results and Discussion flow (in I2)
Page 121 and 122:
Results and Discussion Other intere
Page 123 and 124:
Results and Discussion Figure 3-80
Page 125 and 126:
Results and Discussion KMD 2.4 2.2
Page 127 and 128:
Results and Discussion KMD 1.1 1 Le
Page 129 and 130:
Results and Discussion 3.6.4 Asphal
Page 131 and 132:
Conclusions In conclusion we could
Page 133 and 134:
References References 1. Fay, R. M.
Page 135 and 136:
References 23. Colavecchia, M. V.,
Page 137 and 138:
References 47. Dzidic, I., Petersen
Page 139 and 140:
References Hydroconversion Processe
Page 141 and 142:
References 91. Golovlev, V. V., All
Page 143 and 144:
Appendix Light shredder waste Meas.
Page 145 and 146:
419.4592 C 30 H 59 419.4611 4.6 421
Page 147 and 148:
Liqui Moly car motor oil Meas. m/z
Page 149 and 150:
345.3511 C 25 H 45 345.3516 1.5 349
show all

Development of a Novel Mass Spectrometric ... - Jacobs University

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?