With ValcoPLOT Al2O3 PLOT columns, you don’t need cryogenic equipment to analyze C1 - C5 hydrocarbons. ValcoPLOT Al2O3 columns are deactivated with small salt crystals and stable to 200°C. KCl deactivation produces a relatively apolar column, while Na 2 SO 4 produces columns exhibiting increased retention of unsaturated hydrocarbons.