Direct Mercury Analyzer, DMA-5, DMA-5P

Description

The DMA-5 Series Direct Mercury Analyzer is suitable for the analysis and detection of mercury content in various types of solid, liquid and gas samples; The instrument uses the principle of electrothermal evaporation, gold amalgam enrichment, and cold vapor atomic absorption spectroscopy (CVAAS). There is no need for tedious and complex sample pretreatment steps, and it effectively avoids problems such as cross contamination, memory effects, and environmental impacts that occur in traditional mercury element analysis processes.

Application

Suitable for laboratories in food, environment, medicine, agriculture, petrochemical, mining, nuclear power plants, coal-fired power plants, energy, etc.

Technical Principle

In an oxygen atmosphere, the instrument completes automatic sampling, and performs drying and thermal decomposition in an ashing furnace. The decomposed products are further carried into the catalytic combustion tube by oxygen, and the mercury ions are catalytically reduced to mercury atoms, which are then selectively captured by the amalgamation tube to form gold amalgam. As the amalgamation module heats up rapidly, elemental mercury (Hg) is released and carried by the carrier gas to a cold atomic absorption detector with a single wavelength (253.7nm) for analysis and detection. The amalgamation tube, a highly selective atomic trap, effectively separates the complex matrix in the sample from the elements to be analyzed, thereby completing the direct detection of mercury in the sample. The cold atomic absorption detector uses a measurement method in which multiple specifications of absorption cells are connected in series to obtain a wider detection range.

Features and Advantages

High repeatability, stability, and sensitivity

• The ashing furnace and catalytic combustion furnace are both high-precision PID temperature control systems, which can ensure the consistency of sample pretreatment and eliminate signal drift caused by fluctuations in ambienttemperature;
• With advanced pre-enrichment function, it can achieve more than 40 times enrichment capacity for ultra-low content samples;
• High-efficiency amalgamation tube, using nano-gold-plated quartz sand, has high efficiency in capturing trace amounts of mercury, can achieve multiple captures of samples, greatly improves the sensitivity of the instrument, and ensures rapid absorption and release of mercury;
• The detection system automatically switches the calibration curve according to the sample concentration to ensure the accuracy of the calculation results;
• Double beam light source correction system, dynamic drift correctionand reference beam are used to eliminate the influence of light source fluctuations on measurement results;

Effectively avoid cross contamination and memory effect

• Amalgamation system with constant power heating can quickly and accurately reach the required temperature, avoiding cross contamination and memory effect;
• The detection cell temperature range is from room temperature to 150°C, which effectively removes water vapor interference and avoids data errors caused by the memory effect of mercury;
• Equipped with high mercury protection function, the system automatically and quickly cleans after high-content samples detection to avoid cross contamination;

Low cost and good user experience

• Independently designed catalytic combustion tube and amalgamation tube can be replaced separately to reduce the cost of use;
• No water removal consumables, reducing usage costs while the analysis results are not affected by changes in consumable performance;

Flexible and convenient to use

• The sample tray is easy to switch and adjust, and no power-off is required. Emergency samples can be inserted for analysis at any time;
• The three-dimensional injection structure can realize automatic injection of 100-positionsamples, truly realizing unattended operation for more than 8 hours;

Strong scalability to accommodate multiple application scenarios

• Optional sample pretreatment systems include electrothermal decomposition, stannous chloride reduction, gas capture sampling, directgas sampling, etc.;
• Supportsdifferent liquid sample sampling volumes (5mL~250mL);
• Supportshigh and low concentration switching (mercury trap module);
• Upgradable gaseous mercury detection function, supporting gas bag and adsorption tube sample injection;
• Can be connected to a standard interface balance to automatically import weighing results with one click, avoiding manual recording errors;

Specification