automated microprocessor controller which continuously monitors system operation providing fault detection pressure control and valve sequencing ensuring purifier reliability while minimizing operator involvement by way of example and not limitation level sensors 44 45 pressure sensors 53 54 and temperature sensors can provide information for the controller in order to provide instructions to flow control valves 15 34 52 or pressure relief valves 46 47 48 the valves in the apparatus may be actuated pneumatically by pulling a tap off of the co 2 vapor conduit such as at valve 57 to supply gas for valve actuation the apparatus may include system alarms to detect potential hazards such as temperature or pressure excursions to ensure system integrity alarm and warning conditions may be indicated at the operator interface and may be accompanied by an alarm beeper a human machine interface displays valve operation operating mode warning and alarm status sequence timers system temperature and pressure heater power levels and system cycle count in summary industrial grade co 2 gas may be pulled off of the head space of a supply tank where the supply tank acts as a single stage distillation column stage 1 the higher purity gas phase is passed through at least a coalescing filter reducing the condensable hydrocarbon concentration and resulting in a higher level of purity stage 2 stage 3.