The Earth and Planetary Science Isotope Laboratory (EPSIL) is part of the Department of Earth and Planetary Sciences at Rutgers University, located in the Wright-Rieman labs on Busch Campus. The new laboratory is currently being constructed and is expected to being its operation in the Fall 2022.
The purpose of EPSIL is to explore the origins of the Solar System and Earth through sample-based science. This is pursued through the analysis of meteorites and terrestrial samples using high precision analytical techniques where we resolve compositional variations in the sixth to seventh decimal place! We interpret these cutting edge data in the context of astrophysical models, astronomical observations, and terrestrial planet mantle models to generate meaningful constraints on our origins that are relevant to the broader Planetary Science community.
The laboratory will consist of a clean chemistry laboratory where cosmochemical and terrestrial materials will be processed and purified for analysis. It will be equipped with a thermal ionization mass spectrometer (TIMS; photo below), multi-collector inductively coupled plasma-mass spectrometer (MC-ICP-MS) and laser ablation-inductively couple plasma-mass spectrometer (LA-ICP-MS).
Photo of a thermal ionization mass spectrometer (TIMS) used to extract high-precision isotope ratio information from samples.
Schematic depicting dissolution of a meteorite in concentrated acid. To isolate elements of interest, the resultant solution is passed through a resin bed housed in a column. A sequence of acids is then washed through the column to elute elements of interest that wash off the column in bands. Solutions can then be used for mass spectrometric analysis.
An example of a ~2 g sample dissolution of an iron meteorite (left photo). The sample is digested in high molarity hydrochloric acid at 130 ℃ for at least 48 hours in Teflon beakers. The resulting solution (right photo) contains the digested iron meteorite and phosphide inclusions that could not completely by digested by the hydrochloric acid.
Ion Exchange Chromatography
Photo shows column chromatography used to separate elements of interest from sample matrix. In this photo, the digested sample was loaded onto an anion exchange (~1.4 mL) resin bed. Tungsten, Molybdenum and Platinum can be eluted from this column for high precision isotopic analysis.
After eluting the element of interest from your column, the solution is dried down in a vented laminar flow hood under a heat lamp (left photo). The sample is dried down to a tiny dot. The right photo shows purified Ruthenium after one primary column separation.
Photo of Ruthenium microdistillation. After separating Ru from the sample matrix, the aliquot is further purified by placing the sample and an oxidant (dilute H2SO4 + CrO3) on the cap of a 5 mL conical Teflon vessel, and a reductant (dilute HBr) in the tip of the beaker. The vessel is enclosed in an Al foil jacket (with the tip of the beaker exposed to atmosphere) and heated to 90 ℃ for 2 hours. The body of the beaker is warmed and initiates oxidation of Ru in the cap of the beaker while keeping the tip of the beaker cool to allow reduction of Ru. The resulting solution in the tip becomes red because of the addition of Ru to the dilute HBr.
Purified Molybdenum (blue) solution (~1 uL) is loaded onto a Rhenium filament (left photo). The solution is dried onto the filament with a Lanthanum activator, and loaded into the TIMS for analysis. Right photo shows the glowing filament inside the TIMS source housing, being heated at a temperature of 1229 ℃.