Page 91 - Basic Gas Chromatography
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77                                                                has

                                                          which   according   with   Figure   trade   solution   Because   most   5.4.   PLOT.
                                                          blacks   coated   tailing.   common   that   good   on  badly   Figure   25-m

                                            min.            molecules   lightly   polymer   a   solvents.   in
                                            24    gel.    carbon   One        tails   shown                    column;
                                              N,)               minimize   provided                      IN
                                              and   silica    also     porous   polar   usually   as           sieve

              Gel   6                     T   O,   on  gases   graphitized   organic   are   and   mixture.   a   It   in   problem
              Silica   C   1.H,             18   (Not         they          water   water                      molecular
              1/8”   60°                          fixed   are   separate   solvent   patented   Porapak®.   that   J   on
              x                               Gases           Often   performance
              18’   Temp:  5                1   T   12   Fixed   light   of   adsorbents   and   a   of   Carbopack®.   and   name   analyzing   hydrogen-bond,   solves   1He   3 Ar   40.   5 No   nitrogen

     (GSC)   Conditions:   Column:   Column   Light   Separation   polarity.   their   prepared   trade   and   and

                                          T   6          carbon   nonspecific   and   separation   is   the   to   Porapak®   oxygen
     Phases    4                              for  Good   5.1.   Fig.   of   and   structure   enhance   materials   [3]   under   separating   of   tendency   but   1  I:   of

     Stationary                                          class   nonporous   geometric   to  phase   a  typical   these   for   Hollis   1996   marketed   problem   strong   phases,   Separation




     Solid                                               Another   are   to   liquid   a   shows   5.3   name   In   been   the   to   its   of   stationary   Fig.   5.2.




                                                                                                                  by




     Inlets   silicone   to   supports.   complete   surface   to   usually   instru-   Column   packing   discussed   actual   Supelco   but   specific   will   5.1.   example,   and   and   molecular   metal   is  sieve   their   A   either   sieve.   this   separate   just   weight   names
     and   polar   needed   the   difficult   is   the   9).   both   of   by   GSC,   in   for   chapter   Figure   tailing)   oxygen   alkali   with   13X,9   on   in   GC,   containing   will   sieves   trade
     Columns   highly   phase   some   for   give   will   on   are  coatings   percentage   if  critical   Chapter   in   was  sample   examples   recently   used   developed   this   and   in  shown   this   in   (usually   into   as  known   like   molecular   accordance   and   pores   same   the   molecular   A   for   made   carbon   molecular   molecular   Other



     Packed   a   stationary   limits   that   dependent   not   is   (see   convenience   given   200   available   information.   are  alumina   been   them   is   gel   rather  good   shapes   separated   solids   materials   synthetic   in   A   about   5   the   been   pure   Carbosieves®   the   low   of   water.
           polarity,   Carbowax®.   of   upper   the   amount   is   that   uniform   minimum   the   it   but   temperature   for   for   a   nearly   made   and   have   of  some   silica   are   poor   not   is   using   synthetic   a   on   named   5   has   5A   is  nitrogen   from   have   yields   that   The   for   separation   and



           intermediate   like   amount   the   is   listed   minimum   amount   an   However,   and   length,   meters)   3   phase)  (liquid   providing   been   has   application   (GSC)   gel  silica   phases   listed   uses.   on   gases   number  plate   produce   air   that   nitrogen   and   and   separation   are   sieves   e.g.,  sizes,   and   elute   to   long   that  solids   sieve.  molecular   substituted   be   the   for   methanol





           of   polyglycol   5.1   Table   the   surface,   5.1).   liquids,   error.   column   is   programmed   to   (1   column   reference   columns   provide   PHASES   like   stationary   4.6   Table   common   of   fixed   and   GSC   in   Note   oxygen   Zeolites   classic   These   pore   oxygen   as   of  polymeric  precursor   a   can   use   formaldehyde,   Carboxen®.
           several   a   consideration   support.   usually   is   support   Table   in   polar   for   and   trial   consideration   of   short   best   useful   a   packed   also   solids   used   as   GSC.   their   separation   shapes   used   efficiencies.   gel.   separate   occurring   The   5.2.   effective   of   twice   typical   are   of  a   as  serving   and   also   find   and


           silicones,   OV-275,   and   secondary   solid   limit   the   of   listed   especially   by   capable   usually   are   handling.   the   but   4,   on   suppliers   STATIONARY   adsorbent   solids   in   of   some   typical   peak   the   solids   the   silica   on   easy  to   naturally   aluminoscilicates.   Figure   in   separation   The   takes   CO   Carbosieves®   pyrolysis   and   nitrogen   and   They   and   Ambersorb®



           methyl   A   the   lower   coverage   (also   attain   determined   third   A   is   lengths   Choosing   Chapter   separations   Other   SOLID   Common   of  the   applications   illustrate   A   Although   of   disappointing   nitrogen   is   It   sieves,   shown   approximate   but   by   pores   oxygen   described.   hydrocarbons

    76       like   coat   The   area   ment   and   in   [2].   most     many              pores.   sieve,   case   small   are






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