Page 105 - Basic Gas Chromatography
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91                                                              and         diame-   limited   i.d.   6.6),   These   are   in
                                                     (AROCHLOR)®:   diameter;   microme-   of  operation   small   Fig.   required   microme-   compromise   diameters   seen   analytical


                                         C                           composition;   internal   have   (see   are   operation.   to
              C                          210°                     internal     530      These    320         columns,
             1260   210°   —          1260   @   60                            to   6.2,   Ease   or   best
              @                         1                                                 analyses   systems
             ®   1500  THEORETICAL   T               biphenyls    1)   phase   100   larger   Table   capacity.   250   the   of   internal   compared
            AROCHLOR   ISOTHERMAL   PLATES   T   AROCLOR  ®   SPLIT  30  TO   ISOTHERMAL   are:   from   even   of   one   analysis.   fast   data   of   represent   ease   and   other   ‘“‘widebore”




                         T                           polychlorinated   columns   stationary   briefly.   range  silica   have   row   trace   for   sample   produce   high-speed   diameters   capacity,   all   or   resolution

                         T      minutes   (@)       minutes   {b)   of   capillary   4)   fused   capillaries   columns,   suited   limited   and   and   internal   id.’s   which   in   loss
                                                     separations     thickness;   discussed   well   very   These   sample   against
                         T                             column.    for       i.d.   for   glass   the   efficiency   have   show

                                                     two   capillary   parameters   film   Diameter,   diameters   Some   are   good   columns   columns   6.2,
                         T                                             be           micrometer   not   of   techniques   potential.   6.2.   speed,
                                                     of   (5)   SELECTION   3)   will   mm).   and   because   full   Table   Five-hundred-and-thirty-micrometer   Table
     Selection           f                           Comparison   column;   critical   length;   Each   rate.   Column   column   (0.10-0.53   One-hundred   capacity,   limited   very   have   sampling   their   capillary   of   two   resolution,   reference   of
                         T


     Column                                          Fig.   6.5.   packed   (a)   COLUMN   The   five   column   2)   flow   5)   Internal   Internal   ters   ters.   sample   also   is   columns   special   but   realize   to   Many   row   ters,   between   the   are   measured.   three   row











     Inlets   maximum   column   are   lengths,   hand,   drops   is   phase   high   Packed   and   long   columns   and   two-   capture   and   50-meter   the   of   resolu-   80   to   complex   Packed   meters
     and                    they   long   other   pressure   length   liquid   a   films,   in   resolution.   packed   AROCHLOR   A   1,500,   a   capacities,   entered   amount   better   150,000 plates   2   2000   4000
     Columns   a   to   higher   For   Since   thus   the   on   column   uniform   generates   meter.   per   nonuniform   available   packed   lower   a   on   of   compounds.   electron   an   about   of   on   run   low   31   in   small   much   compared   very   a   with



    Capillary   columns   silica   380°C).   required.   is   popular.   so   across   them;   columns,   greater  producing   packed   thin,   a   which   plates   often   total   plates   while  300,000,   much   same  sample   separation   biphenyl   used   with   number   sample   relatively   have   part   one   a  allows   very   shows   minutes   obviously   is   column   Columns




           fused   (short   term   fused   silica   are  columns   drop   Packed   typical   A   with   surface,   inert   theoretical   thicker,   Thus,   to   show   and   the   of   packed-column   was   glass   plate   a   sample.   same   the   columns   only   that   chromatogram   analysis—52   Arochlor®   capillary   Packed   Capillary   meters   3,000-5,000   K  180-300

           most        COLUMNS   pressure   used.   support,   impractical.   coated   5,000   have   meter.   180,000   plates   of  polychlorinated   i.d.   exhibits   this   shows   so   technique   This   faster   resolution   and         60

           limits   360°C   of   steel-clad   capillary   be  easily   solid   may   be   smooth,   to   hand,   per   from   4,000   chromatograms   a   is   with   capillary   split,   injection”   a   column.   peaks.   Capillary


           that   stainless   OF   OT   why   little   is   can   with   lengths   silica’s   3,000   other   plates   range   only   top   On   blend   of  two-millimeter,   chromatogram   peaks   16   chromatogram   Because   was   rapidly.   and   packed   high   this   the   of   of
           coating   temperature   explains   there   meters,   packed   long   columns   fused   of   typically   the   on   2,000   only   columns   generate   shows   6.5   column.   commercial   This   about   bottom   column.   sample   “split   The   injected   be   peaks,   65   the   even   and   all  resolve   Comparison   N/m



           polyimide   operating   temperatures,   ADVANTAGES   6.1   tubes,   as   60   tightly   making   meters.   Capillary   because   efficiency,   columns,   generate   capillary   typically   Figure   capillary   a   column   detector.   observe   The   capillary   vaporized   column.   to   over   for  minutes   mixture,   not   6.1   Theoretical   (N/m)  plates   plates   X  length


    90                     Table   open   such   are   and   two   1260®,   meter   we   the   sample   tion,   did   TABLE   Length   Total
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