Perkin-Elmer TITAN MPS, User Manual

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3
Proper Use
The Titan MPS (Microwave Preparation System) has been specially developed for
sample preparation for AAS and ICP spectroscopy procedures. The Titan MPS has
been designed to perform chemical digestion procedures under extreme pressure
and temperature conditions in chemical laboratories. Digestion is understood to
mean the decomposition of a solid material by means of a suitable digestion reagent
at increased temperature in a vessel that is permeable with regard to microwaves.
The digestion solutions are directly heated through the absorption of the
microwave radiation by the polar digestion reagent, which generally also contains
ionic components.
Digestion reagents used can include nitric acid (70%), hydrochloric acid (37%),
hydrofluoric acid (49%), phosphoric acid (85%), and sulfuric acid (96%), as well
as mixtures of these acids. The maximum initial weight for organic compounds
depends on the digestion vessel being used and the sample's carbon content and
must always be carefully chosen. The use of organic solvents is strictly prohibited
since the Titan MPS is not designed to prevent the spontaneous combustion of any
solvent vapors that may escape into the oven chamber.
Heating in the pressure vessel can frequently result in digestion temperatures in
excess of 200 °C (392°F). The Titan MPS has been specially developed for sample
preparation for AAS and ICP spectroscopy procedures. Temperature spikes >280
°C (>536°F) can occasionally occur during the course of exothermic reactions and
can result in irreversible damage to the Teflon vessels. Since such scorching can
only be avoided by proper sample and reagent selection by the operator and not by
Observe all operating instructions!
Since sample composition is generally not precisely defined, a certain
residual risk exists when performing pressure digestion processes.
Careful working practices and conscious compliance with safety
regulations can only minimize this risk, not totally eliminate it. Due to
different degrees of mixing, even identical samples can exhibit totally
different behaviors during the course of the digestion! Please strictly
comply with the operating instructions, particularly when handling the
pressure vessels, i.e. when removing and opening the vessels.
Incorrect
handling of the hot, pressurized vessels can result in injuries from
escaping acid vapors!
!
Warning