hydrogen sulfide lab sensor
a sensor for indoor and industrial applications
overview
- Rapid measurements of dissolved hydrogen sulfide.
- Combine temperature and pH probe for total sulfide measurements.
- Calibrated and ready to use.
- Ideal for solutions with depths less than 1m.
- Data loggers available, if required.
This laboratory version of the amperometric H2S micro-sensor has been developed for the in-situ determination of dissolved H2S/sulphide in liquid samples. Because of the partial pressure of the gaseous H2S, the analyte is separated by permeation through the membrane. Inside the sensor the hydrogen sulphide reacts with a redox mediator. The electrochemical oxidation of this formed compound at the working electrode causes a current corresponding to the concentration of the dissolved molecular H2S amount.
The sensor has very short response times and streaming as it is well known from nearly all kind of Clark-type oxygen sensors is not necessary. So, profiling becomes possible with very high signal and local resolution. The sensor works highly selective and there are no signal interferences e.g. to CO, CO2, H2O-vapour, CH4, CS2, dimethyl sulfide (DMS), acetic acid or NH3. Both salt concentrations of up to 40 g/l and turbid or coloured solutions do not interfere with the signal.
For measuring the total sulphide concentration within a range of pH = 5 to 8,5, the sensor must be combined with a pH-electrode and always with a temperature measurement. All sensors are delivered with calibration and temperature compensation data and also with mathematical formulas to calculate the total sulphide concentration.
specifications
| feature | specification |
|---|---|
| measuring principle: | amperometric sensor with redox mediator, 3 electrodes |
| polarization time: | 10-15 minutes (increases due to natural aging) |
| power supply: | 9 ... 30 VDC |
| output: | 0 ... + 3 VDC |
| connector: | Fischer-type |
| materials: | titanium (housing), silicone (membrane), glass (sensor), epoxy resin |
| dimensions: | total length (without connector): 205.0 mm diameter housing (main body): 12.7 mm diameter housing (largest part): 16.7 mm |
| housing: | titanium |
| concentration ranges: | type I: 50 μg/l ... 10 mg/l H2S type II: 500 μg/l ... 50 mg/l H2S type III: 10 μg/l ... 3 mg/l H2S others on request |
| accuracy: | 2% (measuring value) |
| pressure range: | up to 10 bar |
| pH-range: | 0 ... 8,5 pH |
| temperature range: | 0...30°C (for measuring and storage !) |
| response time: | t90%: down to approx. 1 second |
| duration of life: | approximately 5...9 months (depends on H2S stress and on matrix of the analyte) |
| special features: | exchangeable sensor tip, integrated electronic device for the transformation of the current into 0...+3 V DC and for provision of polarisation voltage |