The Model HC2930 is a fixed wavelength IR spectrophotometer designed to perform repetitive quantitative analysis of total hydrocarbons dissolved in non-absorbing solvent. Both volatile and nonvolatile oily samples can be analyzed using EPA methods 413.2 and 418.1. The instrument accommodates standard IR Grade cuvettes and holders (see Hydrocarbon Test Kit) of up to 100mm. Using a 100mm cell in the concentration expansion mode permits analysis of hydrocarbon levels as low as 0.05 ppm.

Water and hydrocarbons absorb in the near IR at 3.4 to 3.5 microns (2930 cm-1). By dissolving the oil content of a sample into fluorochlorocarbon (freon), which is nonabsorbing at 3.4 to 3.5 microns, and following the extraction procedure established in EPA methods 413.2 and 418.1, a working curve is prepared using blank solvent (freon) and known standards. Samples are then compared to the calibration curve in direct ppm readings shown on the instrument. Repeatability is +/-1% on identical samples.

The Model 2930 can also be used with hexane based EPA method 1664, which is an analysis technique that does not require the use of freon as a solvent. A special cell is an optional accessory for this freon-free technique.

Features And Specifications

• Fixed 3.42 micron wavelength and 30 CM-1 bandwidth allows quick 10 second analysis without unnecessary scanning. Response time is a maximum of 40 seconds in damping 2 mode. Furthermore, the operating range permits the use of stable coated quartz optics that are not subject to degradation over time.
• Digital readout in %T, absorbance or concentration. Ranges: 0-100% T; 0-2 absorbance units; and 0-1 and 0-0.1 concentration. Built in scale expansion. Direct ppm readout. Recorder output is provided for optional recorder.
• Built in curve linearizer. Higher concentrations easily calibrated. Small footprint requires minimal benchspace. Portable. Weight: 20 pounds. Dimensions: 14” W x 11” D x 10” H.
• PbSe Peltier cooled detector provides signal to noise ratio of >2500 to 1, instrument stability (drift) <0.01 absorbance units per hour and photometric accuracy of +/-1%.
• Instrument is simple to master and use, requires no maintenance, purging or special atmospheres and is warranted for a full year. Source is enclosed to avoid open source hazards.
• Electrical: 115/230v, 50-60 Hz, 80 watts.