Advanced moisture analyzers measure moisture content in solids, liquids or gases. These systems employ capacitance, IR, automated Karl Fischer titrations (KFTs) or other techniques to obtain more precise and quicker measurements compared with the loss-on-drying method (LOD), in which a sample’s mass is compared before and after it is fully dried using an autoclave or similar instrument.

Capacitive techniques measure moisture by comparing the dielectric constants of water and the sample using electrodes that may or may not be in direct contact with the material. IR moisture analysis is performed by directing an IR beam into the material and examining the ratio of absorbed and reflected wavelengths. In KFT, a photometric or electrometric detector measures the amount of solution absorbed by the sample following a chemical reaction.

LOD methods rely on evaporation, which may not provide accurate results, particularly for samples containing other volatile substances. Advanced moisture analyzers can provide a higher level of accuracy while also providing a palette of options depending on electrical conductivity, overall moisture level, particle size and shape, and other characteristics.

Sinar Technology’s Aquapal III is an automated Karl Fischer Titrator. The KFT reaction can sometimes take a long time to perform and usually requires small amounts of sample with low moisture content (under 0.1%), such as minerals and granules. The Aquapal III automates the process. For samples that interfere with KFT, the Aquapal III can connect to the Aquapal Vaporiser. The Aquapal III is sensitive within 0.1 mg, a range of 1 ppm to 100% of sample and produces results at a rate of 2 mg of sample per minute. Additionally, the system can interface with a computer.

Nyad’s ACT. (Advanced Capacitive Transducer) is a line of application-specific, capacitance-based probes for trace-moisture analysis. Its rugged design is suitable for a range of environmental conditions and is insensitive to flow, pressure and temperature range. The instruments have fully interchangeable sensors and function in gas and nonconductive liquid samples.

MA100Q Infrared Moisture Analyzer from Sartorius is a high-sensitivity thermogravimetric moisture meter suitable for electrically conductive material (above 20 ?/cm) of very dry samples. The system features a readability of 0.001%, with a maximum capacity of 100 g, and a heating unit choice of ceramic IR, halogen lamp or coiled quartz radiator. The MA100Q has several heating modes as well as up to 30 programmable templates.

The advanced moisture analyzer market has an estimated value of $10 million. The primary applications are for foods, pharmaceuticals, chemicals and minerals. Recent quality questions regarding adulterants in foods could potentially lead to increased usage of moisture analysis equipment.

Advanced Moisture Analyzers at a Glance:

Leading Suppliers

• Sinar Technology

• Sartorius

• Nyad

Largest Markets

• Food

• Chemicals

• Minerals

Instrument Cost

• $2,000–$10,000