Polyynes: Synthesis with the Submerged Electric Arc - Polyynes: Synthesis, Properties, and Applications - page 150

8 Polyynes: Synthesis

with the Submerged
Electric Arc

Franco Cataldo

CONTENTS

8.1 Introduction .................................................. 156
8.2 Experimental Aspects on the Synthesis and Analysis of
Polyynes with the Electric Arc.................................. 157
8.2.1 Synthesis of Polyynes in a Submerged Electric Arc ...... 157
8.2.2 HPLC Analysis of the Polyynes ........................ 159
8.2.3 Study of the End-Capping of the Polyyne Chains........ 159
8.2.4 The Electric Arc Between Graphite Electrodes in
n-Hexane .............................................. 159
8.2.5 The Electric Arc Between Graphite Electrodes at Very
High Current Density .................................. 160
8.2.6 Electric Arc Between Titanium Electrodes in n-Hexane . . 160
8.2.7 The Electric Arc Between Titanium Electrodes in
Methanol: A Comparison with Carbon Arc ............ 161
8.3 Results and Discussion ........................................ 161
8.3.1 Some Kinetic Aspects on the Formation of Polyynes .... 161
8.3.2 Detection and Identification of Polyynes by
HPLC-DAD and Other Analytical Techniques . . ........ 164
8.3.3 PAHs as Byproducts Formed with the Polyynes
During Arcing .......................................... 169
8.3.4 The Role Played by the Nature of the Electrodes in the
Polyynes Formation .................................... 174
8.3.5 Formation of Carbon Coke or Pyrocarbon:
A Comparison with a Series of Halogenated Solvents.... 176
8.4 Conclusions . ................................................... 177
Acknowledgments .................................................. 178
References .......................................................... 178

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