DMA-2020 Direct Injection Mercury Analyzer

Direct injection mercury analyzer

2. Instrument principle

In an oxygen environment, the sample is automatically injected and dried and thermally decomposed in an ashing furnace. The decomposed products are further loaded into the catalytic combustion tube by oxygen, and the high valence mercury is catalytically reduced to the ground state, which is then selectively captured by a mercury trap at low temperatures to form a gold amalgam. As the mercury trap rapidly heats up, mercury (Hg) is released and carried by the carrier gas to an atomic absorption detector with a single wavelength (254nm) for analysis and detection. By using a highly selective atomic trap such as a mercury trap, effective separation of complex matrices and analyzed elements in the sample has been achieved, thereby achieving direct detection of mercury in the sample.

The atomic absorption detector adopts a measurement method of connecting long and short absorption cells in series, which can obtain a wider detection range.

The detection of mercury using the principle of thermal cracking gold amalgam enrichment cold atomic absorption is applicable to domestic and foreign standard methods such as GB5009.17-2021, EPA7473, HJ923-2017, HJ917-2017, HJ910-2017, etc.

3. Application Fields

DMA direct injection mercury analyzer can directly inject solid, liquid, and gas samples. The method is simple, does not require any pre-treatment, has high sensitivity, fast detection speed, saves time and effort, and has no reagent pollution or environmental pollution.

Sample inspection in industries such as disease control, food and medicine, customs, and third-party testing;

Water quality inspection of urban water supply and drainage systems;

Environmental sample inspection;

Clinical fluid and toxicological pathological examination;

The field of cosmetics toxicity testing requires trace detection of Hg element.

4. Working environment

Power supply: AC voltage: (220 ± 22) V, frequency: (50 ± 1) Hz;

Temperature: (15-30) ℃;

Relative humidity: ≤ 80%;

Instrument power consumption: startup: ≤ 1000W; operation: ≤ 600W;

5. Performance indicators

5.1 Instrument Parameters and Technical Indicators

5.1.1 Injection volume: Solid 1500mg, Liquid 1500 μ L

5.1.2 Light source: Low pressure mercury lamp (imported) wavelength: 253.65nm

5.1.3 Detector: Silicon UV photodetector (imported)

5.1.4重复性： RSD＜2.0% @ 1ng

Detection limit: 0.005ng

Measurement range: Long pool: 0ng~20ng; Short pool: 20ng~1000ng

Correlation coefficient (r): ≥ 0.9990

5.1.5 Temperature range of catalytic combustion furnace: 100 ℃~1000 ℃

Heating power of mercury trap: 0W~100W

Temperature range of detection pool: 100 ℃~150 ℃

5.2 Technical specifications for instrument configuration

5.2.1 Automatic sampler: Adopting a four-dimensional stereo automatic sampler, it can achieve automatic sampling of 100 samples.

5.2.2 Direct injection mercury analyzer

5.2.2.1 Gas path system: Adopting a dual channel integrated electronic mass flow gas path control device, the flow range is (0-1000) mL/min, continuously adjustable, providing stable flow rate, and also having real-time pressure and flow rate monitoring and alarm functions;

5.2.2.2 Temperature Control System: The ashing furnace, catalytic combustion furnace, and detection cell are all high-precision PID temperature control systems to ensure consistency in sample pretreatment and eliminate signal drift caused by fluctuations in environmental temperature, ensuring high repeatability and stability;

A mercury trap system with constant power heating can quickly and accurately reach the desired temperature, avoiding cross contamination and memory effects;

5.2.2.3 Detection System:

The dual absorption cell series design meets the detection needs of high, medium, and low concentration samples;

The dual beam light source calibration system eliminates the effects of light source drift and fluctuations in real time, ensuring the accuracy of the results;

High resolution sampling circuit design, strong anti-interference ability, adaptable to high and low range switching, achieving accurate and reliable data transmission system.

5.2.3 Data processing system (software system)

5.2.3.1 It can achieve comprehensive system self inspection, with graphical equipment status monitoring and parameter display (gas flow rate, pressure, power, etc.), instrument self diagnosis, and abnormal state alarm;

5.2.3.2 Online and offline operation modes, independent data analysis module, supporting simultaneous opening and switching of multiple data files for processing;

5.2.3.3 Real time monitoring of signal curves, with the ability to load background spectra for comparison;

5.2.3.4 Flexible report templates, with built-in simple, universal, detailed, and various performance testing report templates that can be selected as needed; Support custom templates;

5.2.3.5 The test results can be converted into at least 5 commonly used file formats, including PDF, XLSX, DOC, TXT, etc., and support LIMS data reading;

5.2.3.6 LIMS Implementation Method: SQLite is used for data storage, supporting the export of various formats such as text, images, and Excel files. Data can be reported through WebService, HTTP, and other methods;

5.2.3.7 It has user permission management and audit tracking functions. Administrators can classify and review logs, and automatically record important user operations, in compliance with GMP/GLP requirements;

5.2.3.8 Monitoring and alarm information

Equipped with a comprehensive sensing system, digital gas path pressure monitoring (inlet and outlet), gas path flow monitoring, multi temperature zone temperature monitoring, etc;

Operation protection alarm system, no carrier gas safety protection, heating wire short circuit and open circuit protection, etc;