Digestors
Systems and equipment designed to perform safe chemical digestions of a sample.
Typically performed on foodstuffs, the Kjeldahl method or test is designed to determine (or confirm) the amount of protein in soil, wastewater, fertilizer, and other materials. They are used in agricultural and environmental testing to measure trace metals, nitrates, and ammonium.
The method converts proteins, amines, organic compounds and other nitrogen compounds into ammonia compounds. A caustic is added to release the ammonia, which is then distilled and titrated. Samples are heated from 360o to 410°C in the presence of concentrated sulfuric acid and a catalyst. This decomposes or digests the sample and frees the nitrogen. The digestion is complete when the liquid is clarified and the fumes are released. The samples are cooled, and the liquid is distilled and titrated.
Several catalysts are available (called Kjeldahl tablets), and usually contain a mixture of copper and titanium. Some catalysts work better with specific materials, and others are more environmentally friendly. Digestions can be performed manually, but are somewhat hazardous and should always be performed under a chemical hood.
Automated or semi-automated digestors reduce the risk to the person performing the Kjeldahl testing. Some equipment is designed to heat to the maximum temperature in an hour and cool down faster for more efficient digestions. Some perform only the digestion portion of the procedure, and the distillation and titration must occur separately. More complete digestion systems incorporate all of the necessary steps and deliver a final result. The choice of digestor type, including rapid digestors , depends on the workload, speed required, and sample volume.
BUCHI KjelDigester K-449
KjelDigester K-449 offers fast and safe digestion of up to 20 samples simultaneously. This fully automated model offers a convenient automatic lift for raising and lowering the sample tube rack, and a programming mode so that all digestion methods can be saved.
Parr™ General Purpose Acid Digestion Bombs
Acid digestion bomb for organic and inorganic analytical samples
Velp Scientifica™ Automatic Kjeldahl Digestion Unit DKL Series
Automatic Kjeldahl Digestion Units with aluminum heating block that offers excellent thermal stability and homogeneity. The DKL Series is supplied with an auto lift, an auto suction cap, test tubes, sample rack and drip tray.
Labconco™ Kjeldahl Rapid Digestor-25
Extra-fast heating and cool-down time
Labconco™ Kjeldahl Micro Digestor
Individual electric heaters with adjustable controls
BUCHI SpeedDigester K-439
Combines all advantages of IR and block heating digestion systems to revolutionize Kjeldahl digestion. K-439 is the only programmable IR digestion system with an integrated temperature sensor, making fast IR digestion achievable at precise temperatures.
Accessories for Labconco™ Kjeldahl Rapid Digester-25
Required for use with Labconco Rapid Digestors
Labconco™ Kjeldahl Digestion Tubes for Rapid Digestor-4 and Rapid Digestor-25
For Rapid Digestor-25 and Rapid Digestor-4
BUCHI Scrubber K-415 TripleScrub
A three-step gas scrubbing instrument with a powerful pump and condensation, neutralization and adsorption steps. It protects the user and the environment not only by neutralizing poisonous fumes and reaction gases, but also by minimizing the use of cooling water.
Velp Scientifica™ DK8 Kjeldahl Digester System
This digestion unit with an 8-position aluminum heating block offers ideal thermal homogeneity.
Velp Scientifica™ DK 42/26 Digestion Unit
Kjeldahl Digestion Units with 42-position aluminum heating block that offers an excellent thermal homogeneity for micro-kjeldahl applications.
Velp Scientifica™ DKL12 Automatic Kjeldahl Digester System
This digestion unit with a 12-position aluminum heating block offers ideal thermal stability and homogeneity.
Velp™ Scientific DK6 Digester
Kjeldahl Digestion Unit with a six position aluminum heating block that offers high thermal homogeneity.
Velp Scientifica™ DK6 Kjeldahl Digester System
This digestion unit with an 6-position aluminum heating block offers ideal thermal homogeneity.