Oil and grease (hexane extractables) is a general indicator of the amount of hydrocarbon in a water supply. It is used around the world to indicate pollution and to help ensure reliable waste treatment plant operation.   
   
In the past this measurement was often made by extracting the water with a chlorofluorocarbon solvent and infrared used for the measurement step. With concern about the ozone layer and important toxicity concerns, these solvents have been outlawed in many countries and n-hexane is now the extraction solvent of choice. A simple gravimetric measurement is used for the analytical step.   
   
The SPE-DEX 3100 extractor (now CE-marked), coupled with the safe solvent delivery system, Pacific Premium solid phase extraction disks, in-line extract drying, the Speed-Vap IV Evaporation system, and the SolventTrap og provides a full workflow process for oil & grease analysis.