UNICUBE trace

Matrix-independent determination of N and C at trace levels

The UNICUBE trace measures low-level nitrogen and carbon concentrations in solids and highly viscous liquids with a detection limit of 10 mg/kg. Its speciality: nitrogen and carbon determination are carried out using the Dumas method, which involves the removal of interfering gases during reduction and subsequent detection of the target gases using a thermal conductivity detector. As such, the UNICUBE trace is able to combine the benefits of the matrix-independent Dumas method with high sensitivity.

With UNICUBE trace, sample digestion is carried out via catalytic combustion at a temperature of 950 °C, with the nitrogen and carbon-containing components in the sample forming a mixture of different oxides and N2. The resulting gases then pass through the reduction tube, where carbon compounds are safely reduced to CO2 and nitrogen compounds to N2. After removing other combustion products like H2O and SO2, CO2 and N2 are measured by thermal conductivity detection.

The system is designed for easy, low-maintenance operation; matrix-independent analysis allows the use of a standard ‘universal’ calibration for any sample type. The front door of the analyser opens to give excellent access for the replacement of consumables – exchanging the combustion and reduction tube is simple, thanks to the slide-out furnace.

Specifications:
High-temperature combustion:
UNICUBE trace offers quantitative sample digestion at up to 1,200 °C – with a 10-year furnace warranty – and is able to deliver complete conversion of all N components into N2. The jet injection of oxygen directly to the sample leads to the highest oxygen concentrations at the point of combustion, while minimising gas consumption.

Largest weighing range:
The weighing range encompasses micro (less than 1 mg) and macro (around 1 g of soil) applications, depending on requirements, and can be used to analyse up to 20 mg of organic matter.

Largest dynamic range of element concentrations and element ratio:
UNICUBE trace supports element concentrations and ratios up to 50 mg C abs. or 10 mg N abs. (or 100%, depending on analysis mode and sample matrix), from ppm to 100%, LOD 10 ppm N and C

Multipoint calibration
Offering matrix-independent stability for months at a time.

PC-based instrumentation control
Full digitalisation of the instrument allows for remote operation from a standard PC and perfect results, even when dealing with unknown or heavily variable sample matrices. The integrated standard sample feeder accommodates 120 samples, with 21 CFR part 11 functionality also available.

One simple instrument for all applications
UNICUBE trace requires no expensive special catalysts, facilitating easy ash removal from the combustion tube and offering long-lasting components to ensure a low cost of ownership.

Clean, safe and fast
Each analysis only takes a few minutes and uses helium carrier gas, with no aggressive or toxic chemicals needed.

Easy installation requirements
UNICUBE trace takes up just 48 x 55 cm of benchtop space and operates using a single power supply (230, 110 or 100 V) and two gases, providing lengthy periods of maintenance-free operation.