Clean Lab Complex
Digestions and chemical separations of samples for analysis as solutions by inductively coupled plasma mass spectrometry (ICPMS) are carried out in a state-of-the-art class 100 clean laboratory complex in MAF-IIC. Low-blank reagents (water and acids) are also produced in this complex. Where possible, plastics and non-metal synthetics have been used for construction of piping, faucets, bench surfaces, door handles, ceiling supports, etc. Where metal present, it is sealed with an inert epoxy paint. This provides an ultra-clean environment suitable for low-level analysis of the concentrations and isotopic compositions of a wide variety of chemical elements.
The complex comprises four main rooms plus an ante room for changing into clean room attire and a room for reagent storage. The rooms are designed to have effective flow of HEPA (high efficiency particle attenuation) filtered air through the complex. Air flows are balanced so that there is positive flow from the back rooms of the complex toward the front rooms and the outside hallway.
Each of the four main rooms in the complex is dedicated to a specific task. The first room, adjoining the change room, is used for sample dissolution. It is equipped with a mechanical convection oven, a Milestone high-pressure microwave digestion system and hot plates in a fume-hood. Sample dissolutions can be performed either in the microwave, in the oven using up to three 125ml Parr bombs and Savillex Teflon microcapsules or on the hot plates using Savillex Teflon beakers.
A second room, enclosed from the rest of the complex, is used as a balance room in order to weigh samples and isotopic spikes. It contains a high-precision dual range micro-balance, a top loading balance and micro-centrifuge. For mineral identification and weight estimates for spike additions, a x7 to x60 stereo-microscope equipped with a 1Mpixel digital camera is also available.
A third room is dedicated for acid distillation and water purification. The acids (HF, HCl, HNO3) are doubled distilled in six (two per acid) Savillex Teflon sub-boiling distillation units built inside a fume hood. To provide ultra-pure water (18 MΩ /cm), building water is first sent to a Millipore RIOS 5 reverse osmosis system and stored in a 60L Millipore tank. The water from the tank is then sent to a Millipore Milli-Q Gradient distillation unit producing metal blanks at the parts per trillion level.
Finally a fourth room, and the cleanest of the entire complex, is equipped with two fume-hoods (one suitable for perchloric acid) and two ultra-clean boxes (for ion-exchange resin separation). It serves as the chemical separation/sample final preparation room. This is where chemical separations for isotopic tracer studies using Nd, Sr, Pb and other elements are carried out.