2015 Microwave Digester Survey Results

Microwave-acid digestion is a common sample preparation step for atomic absorption, atomic emission, or inductively coupled plasma analysis of metals. Microwave digestion takes minutes,
compared with hours for conventional hot plate digestion. 

By Trevor Henderson

Because it uses high temperature and strong acids—commonly nitric and hydrofluoric—microwave digestion mineralizes any matrix. For example, EPA method 3052, based on microwave, provides total metal analysis from soil, sediments, sludge, oils, plastics, and biological materials.

Top 5 Questions You Should Ask When Buying a Microwave Digester

  1. What is the system’s maximum microwave power output? Microwave energy heats substances quickly to high temperatures. The higher the temperature, the faster and more completely substances are digested. Extractions also need sufficient power, as some solvents can act as a heat sink and are difficult to heat.
  2. Can the system monitor and control every vessel? Temperature and pressure monitoring and control are extremely important. Inadequate safeguards can result in damaged vessels and equipment, and a lack of temperature and pressure control can pose a safety hazard to lab personnel.
  3. How many samples can be processed per run? Though the number of samples processed is dependent upon your laboratory’s needs, planning for growth is always a good idea.
  4. Does the company offer free applications support? Do they offer dedicated, direct service support and local factory- trained field service technicians? Dependable applications and service support are essential since you never know what may go wrong.
  5. How user-friendly is the system? As with many instruments, if a system is very complicated to operate, it generally becomes either a glorified shelf to store things on or a headache to those having to operate it. The easier a microwave system is to use, the better off you will be. Also make sure the vessels are easy to handle and set up.

Acid types used by survey respondents for microwave digestion:

Nitric acid 87%
Hydrochloric acid 63%
Hydrofluoric acid 37%
Sulfuric acid 27%
Phosphoric acid 10%
Perchloric acid 7%
Borofluoric acid 3%
Other 3%

Microwave digestion applications as reported by survey respondents:

Analyzing metals 37%
Trace metal analysis 27%
Biological sample analysis 13%
Material analysis 7%
Oil and lubricant analysis 7%
Soil analysis 3%
Other 7%

Nearly 45% of respondents are engaged in purchasing a new microwave digester. The reasons for these purchases are as follows:

Replacement of aging systems
Addition to existing systems, increase capacity
Setting up a new lab
First time purchase
Replacement of a damaged

Top 10 Features/Factors Respondents Look for When Purchasing a Microwave Digester:

High Durability 83%
Service and Support 76%
Intuitive Controls and Software 67%
Low Maintenance 62%
Price 51%
Vendor Reputation 45%
Small Footprint 55%
High Sample Weight Capacity 31%
Short Cool-Down Time 29%
Speed of Heating 27%

For more information on microwace digesters, including useful articles and a list of manufacturers, visit www.labmanager.com/microwave-digesters

See the most recent survey results here

Categories: Surveys

Published In

Future Labs Magazine Issue Cover
Future Labs

Published: July 13, 2015

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