SRC Design and Operation

At the heart of the UltraWAVE is a Teflon lined, 1L stainless steel reaction chamber, which is also the microwave cavity. This allows the design of the1500W microwave source to be perfectly matched to the cavity shape for optimum microwave distribution and fast, even heating. Samples are weighed into vials and placed in a rack, which is lowered into the reaction chamber. The chamber is sealed and pre-pressurized with inert gas, which acts as a “cover” over the samples, preventing cross contamination. Unlike closed vessel digestion, different sample matrices can be digested together, and the chamber is water cooled, which makes cool down time very fast.

Safety

Like all Milestone products, the UltraWAVE has been designed with operator safety of paramount importance. A thick acrylic shield surrounds the work area, which lowers into position automatically as the chamber is closed.
A run can not be started unless the chamber clamp is in position, and the clamp cannot be released until the chamber is cool, and pressure has been released. The PID controller monitors pressure, digestion and chamber temperature 20 times/sec, adjusting microwave power instantaneously to control even highly exothermic reactions.

Performance and Control

The UltraWAVE is an ultra high performance system, operating up to 199 bar pressure and 300°C, and ensuring complete digestion of even the most difficult samples. And unlike closed vessel digestion, every sample is under direct pressure and temperature control; no need to rely on indirect control such as infrared temperature sensors.
This assures complete control of the digestion process in every sample. No need to use a reference sample, and no venting of vessels due to over pressure. The UltraWAVE reaches temperature faster, cools faster, and is capable of higher pressure and temperature than any closed vessel system.

Digestion Sequence

This diagram shows how a digestion is performed in the UltraWAVE.

Racks and Vials

Available sample rack configurations include 4, 5 and 15 position, plus a 22 position rack for microsamples. Vials are available in glass (disposable), quartz or TFM, and are fitted with Teflon caps, loose fitting to ensure pressure equalization. Numbered rack trays give the operator an easy visual check of vial number.
UltraWAVE sample racks fit easily on a balance, so samples can be weighed directly into vials already loaded into a rack. Unlike closed vessel digestion, no vessel assembly or disassembly is required, and with disposable vials, no cleaning step is needed, greatly increasing productivity.