The measurement of total oil and grease (TOG) and total petroleum hydrocarbons (TPH) in water is important not only in pollution monitoring but also in site remediation
The use of freon has now been banned under the Montreal Protocol, so the ASTM's new method D 7066-04 using the environmentally acceptable S-316 solvent (a dimer/trimer of chlorotrifluoroethylene) as an extraction solvent will be welcomed.
The new method follows the S-316 extraction by measurement of infra-red absorption at 3.4 microns in a fixed-wavelength infra-red analyser such as the Wilks Infracal Model CVH.
The Infracal CVH was one of the instruments used in the development of the new method, and can determine TOG and TPH levels down to 1-2ppm in 10-15 minutes, including extraction.
The scope of ASTM D 7066-04 is up to 100ppm, but the Infracal CVH can give reliable measurements to well over 500ppm.
The instrument is extremely portable and is very easy to use, making it ideal for on-site measurements.
UK distributor for the Infracal CVH is Quantitech.
