8690-2007
- Hydrocarbon and hydrogen-selective
- Detects down to 500ppm
- Gasless operating capability
- Inexpensive and rugged
- Built-in spare element
The CCD detector sensor is rugged and can be expected to last a long time. A second sensor is included in the detector housing at no extra cost, providing a built-in replacement should the first sensor become inoperable. Replacement sensor sets are installed in minutes without tools and are very economical, making this detector a good choice for academic settings where the detector may be damaged by inexperienced operators.
The Catalytic Combustion Detector consists of a tiny coil of platinum wire embedded in a catalytic ceramic bead. A small electric current flows through the platinum coil, heating the ceramic bead to around 500°C. The CCD is maintained in an oxidative environment typically by using air as carrier gas. When a hydrogen or hydrocarbon molecule impacts the hot bead, it combusts on the surface and raises the temperature and resistance of the platinum wire. This resistance change causes the detector output signal to change, thus producing a peak. The brass detector housing is mounted on a stainless steel bulkhead fitting, which is secured directly to the wall of the GC column oven.
The CCD is about as sensitive as a TCD, but it has the hydrocarbon selectivity of an FID while capable of operating on air alone. Because the CCD needs no compressed gases like hydrogen or helium, it can be used in SRI’s Gas-lessTM GCs where a built-in, ″whisper quiet″ air compressor supplies the ambient air carrier gas.
The CCD can also be used as a hydrocarbon monitor in non-chromatographic applications where the CCD senses the total hydrocarbon content of a flowing air stream, or as a hydrogen/hydrocarbon leak detector.
8690-2007 CCD detector
8670-2007 Replacement CCD detector housing (2 sensors in 1 housing)