Geochemistry Labs

The Geochemistry facility contains several laboratories (wet laboratories, HF laboratories) and instruments to analyse the chemical composition of natural samples and experimental products. In addition to the equipment listed below, geochemical experiments can be conducted in the Petrology and fluid-rock interaction facility, and geochemical analyses can be conducted with instruments in the Electron microscopy facility.

Inorganic geochemistry laboratory

Enlarge

The inorganic geochemistry lab is equipped with a SPECTROGREEN ICP-OES and a SYKAM S150 Plus IC, which allow elemental analysis of inorganic compounds in solution. The instruments are used to measure concentrations of major and trace elements as well as ionic compounds in digested geological samples, leachates, and natural waters.

The ICP-OES can measure concentrations of the following elements in a range of materials and at concentrations from μg/L (or lower) to g/L:
Ag, Al, As, B, Ba, Be, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Li, Mg, Mn, Mo, Na, Ni, P, Pb, Sb, Se, Si, Sn, Sr, Tl, V, Zn

The IC is equipped to analyse concentrations of the following anions and cations in the range of mg/L:
F^-, Cl^-, Br^-, NO₃^-, NO₂^-, PO₄^3-, SO₄^2- and Li⁺, NH₄⁺, Na⁺, K⁺, Mg²⁺, Ca²⁺

Wet chemistry lab

Enlarge

Our wet chemistry laboratory is equipped with fume hoods, components for sample preparation and classic wet chemical treatment possibilities, and instruments for chemical analysis. The wet chemistry lab is complemented by a separate lab equipped with fume hoods for the use of hydrochloric acid (HF).

The facility further includes:

• a Heraeus M110 high temperature furnace for the determination of loss on ignition (LOI) of volatile components (e.g.: H₂O) when heating rock powders up to 1100 °C.

Enlarge

• XYLEM SI Analytics TitroLine 7000 for automated titration and determination of Fe²⁺ concentrations in sample solutions.

FlashSmart Elemental Analyser

Enlarge

Many experimental and field-based studies deal with dissolved COH-fluid concentrations in silicate- and carbonatite melts and minerals. The ThermoScientificTM FlashSmartTM CNHSO elemental analyzer enables quantitative analysis of 2-10 milligram of synthetic or natural materials for carbon, nitrogen, hydrogen, sulfur and oxygen concentration. The elemental analyzer operates on a modified Dumas method where <10 mg of material (solid or liquid) is enclosed in tin or silver containers and subsequently get combusted at approximately 2000°C in presence of high-purity oxygen with helium acting as carrier gas to an adjacent gas chromatograph. CNHSO are detected by thermal conductivity and are recalculated to weight percent volatiles relative to the initial sample mass.

Currently, a set of 10 one bar gas mixing furnaces is ready to use for various experimental purposes. Their flexible design allows a wide variety of experimental investigations: 2 furnaces are equipped with Brookfield viscosimeters for rheological investigations, while 1 furnace is equipped with a Mettler Toledo 104 balance for in situ density determinations. One furnace is used for oxidation state determinations of various metals in silicate melts (Fe2+/Fe3+, Eu2+/Eu3+, Cu1+/Cu2+). Synthesis of geomaterials or glasses under controlled fO2 (oxygen fugacity) conditions are only one standard method routinely applied. Six one bar furnace assemblages, including all necessary experimental infrastructure (gasmixing systems, oxygen sensor assemblages, etc.), are reserved for element partitioning studies concerning moderately and highly siderophile elements,. A new area of research will be the control of sulphur fugacity applying SO2 containing gas mixtures in planned partitioning studies to investigate this important parameter in respect to planetary segregation and core formation processes.