Agilent G6602-64002 is the 230 V version of the Agilent 355 Sulfur Chemiluminescence Detector (SCD), a highly sulfur-selective detector for gas chromatography. The detector uses chemiluminescence generated from the reaction of sulfur monoxide produced during combustion of sulfur-containing analytes with ozone, providing high sensitivity, a wide linear range, and exceptional selectivity against hydrocarbon matrices.
The 355 SCD is suitable for trace-level determination of sulfur compounds in petrochemical, fuel, environmental, food, and other GC applications.
Detection Principle
The Agilent 355 SCD is an element-selective sulfur detector.
Sulfur-containing compounds eluting from the GC column are combusted in the Dual Plasma Burner, converting sulfur to sulfur monoxide (SO). The SO is transferred under vacuum to the reaction cell, where it reacts with ozone and produces chemiluminescent emission.
The emitted light is:
- optically filtered,
- detected by a photomultiplier tube (PMT),
- amplified and converted into an analytical signal.
This approach provides very high selectivity for sulfur-containing compounds.
Dual Plasma Burner
The Dual Plasma Burner uses two sequential combustion zones:
- an oxidant-rich lower plasma,
- a hydrogen-rich upper plasma.
This configuration promotes efficient sulfur conversion while oxidizing hydrocarbon matrix components.
Typical SCD burner temperature is 800 °C.
Chemiluminescence Reaction Cell
Combustion products are drawn into the reaction cell under vacuum.
Inside the cell:
- SO reacts with ozone,
- chemiluminescent emission is generated,
- UV light passes through an approximately 300–400 nm bandpass filter,
- the emitted signal is detected by the PMT.
This configuration minimizes response from non-sulfur compounds.
Detector Performance
Sensitivity
- Typical <0.5 pg S/s
- Based on approximately 3.3:1 signal-to-noise
Selectivity
- Typical >2 × 10⁷ g S/g C
Linearity
- >10⁴
Precision and Stability
- <2% RSD over 2 hours
- <5% RSD over 72 hours
Typical Operating Conditions
- Burner temperature: 800 °C
- Burner pressure: approximately 250–400 Torr
- Hydrogen flow: typically 40–50 sccm
- Oxidant flow: typically 60–65 sccm air
- Reaction-cell pressure:
- 4–8 Torr with oil-sealed pump
- 6–12 Torr with dry piston pump
- Typical background noise: 0.3–2.0 mV
Ozone Generator
The detector incorporates a corona-discharge ozone generator.
Ozone is supplied to the chemiluminescence reaction cell to react with sulfur monoxide generated by the burner.
Typical ozone flow:
- 20–30 mL/min
- approximately 3–6 psig inlet pressure
Vacuum System
The 355 SCD requires an external vacuum pump.
Supported configurations include:
- Edwards RV5 oil-sealed rotary pump
- oil-free dry piston pump
The higher vacuum produced by the oil-sealed pump can provide slightly lower detection limits by reducing residence time in the reaction cell.
Signal Output and Controls
The detector provides analog output for connection to a chromatography data system or integrator.
- 0–1 V
- 0–10 V
Front-panel functions include:
- signal monitoring,
- reaction-cell pressure display,
- signal attenuation,
- baseline offset adjustment,
- vacuum pump control,
- ozone-generator control.
GC Compatibility
The Agilent 355 SCD is designed as a stand-alone sulfur-selective GC detector and can be mounted on different GC platforms using the appropriate mounting kit and interface.
The offered configuration is associated with G6644A.
Technical Specifications
- Model: 355 SCD
- PN: G6602-64002
- Technique: GC-SCD
- Detected Element: Sulfur
- Detection Principle: Sulfur chemiluminescence
- Sensitivity: typically <0.5 pg S/s
- Selectivity: >2 × 10⁷ g S/g C
- Linearity: >10⁴
- Precision: <2% RSD / 2 h
- Long-Term Stability: <5% RSD / 72 h
- Burner Temperature: typically 800 °C
- Burner Pressure: typically 250–400 Torr
- Hydrogen Flow: typically 40–50 sccm
- Air Flow: typically 60–65 sccm
- Reaction Cell Pressure: typically 4–8 Torr with RV5 / 6–12 Torr with dry piston pump
- Signal Output: 0–1 V / 0–10 V
- Power Requirements: 220–240 VAC, 50/60 Hz
- Power Consumption: 650 W
- Dimensions (H × W × D): approx. 40.6 × 23.4 × 55.3 cm
- Weight: approx. 15 kg
