Alternative capillary column to 30% G22 phase support S1D

Question

in ether USP monograph (2-mm &times; 3.7-m stainless steel; with 30% phase G22 on 30- to 60-mesh support S1D) is required for "Limit of Low-Boiling Hydrocarbons" analysis but it is packed column, and we want to find alternative capillary column.

Thanks in advance. 
 
 Dami&aacute;n Walton

Dr. Know · Accepted Answer

Hi Damian, 
 G22 is B is(2-ethylhexyl) phthalate and there is no capillary equivalent (see also GC and GC/MS Columns - USP Designations ). Even as packed phase it falls under REACH as carcinogenic chemical and we don't offer it anymore. 
 Looking at the McReynolds constants for BEHP the closest capillary phases would be CP-Sil 19 CB/VF-1701ms, VF-35ms or DB-Alc2, all slightly less polar and a changed selectivity.

Phase 
 Class 
 McR1 
 McR2 
 McR3 
 McR4 
 McR5 
 Euclidean Distance 
 Cosine Similarity 
 CP-Index

Bis(2-ethylhexyl) phthalate, BEHP 
 Packed 
 92 
 186 
 150 
 236 
 167 
 0.0000 
 1.0000 
 19.7

USP G22 
 Packed 
 92 
 186 
 150 
 236 
 167 
 0.0000 
 1.0000 
 19.7

DB-ALC2 
 Capillary 
 84 
 172 
 159 
 241 
 161 
 0.0913 
 0.9981 
 19.4

CP-Sil 19 CB 
 Capillary 
 82 
 170 
 157 
 236 
 160 
 0.0980 
 0.9983 
 19.1

VF-1701ms 
 Capillary 
 82 
 170 
 157 
 236 
 160 
 0.0980 
 0.9983 
 19.1

VF-35ms 
 Capillary 
 80 
 179 
 146 
 224 
 188 
 0.1212 
 0.9964 
 19.4

Regards, 
 Norbert

Alternative capillary column to 30% G22 phase support S1D

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