Transport Effects in a Microchemical Reactor
Introduction
What are microchemical
reactors?
Microchemical reactors, or microreactors, are miniaturized reaction systems containing one or more reaction channels with sub-centimeter dimensions. Microreactors enable the introduction of new reaction procedures in chemistry, molecular biology and pharmaceutical chemistry. They also offer tremendous opportunities in the traditional chemical engineering sub-disciplines of catalysis, transport phenomena, and reaction engineering. Some examples of microreactors are shown below.
Source: Klavs F. Jensen, AIChE Journal 1999, Vol. 45, No. 10, pp2051
How to manufacture
microreactors?
Generally, microreactors are produced by
micro-fabrication or micro-lamination.
Microreactors are normally produced from metals, glass, silicon, and
ceramic, due to their chemical inertness and temperature stability.
Advantages of microreactors
over large-scale processes:
1. Safer operation due to:
á Quicker transport process
á
On-site
or on-demand production
á
Novel
reaction conditions
2. Larger surface area to volume ratio, and new
catalyst testing with tiny amount of catalyst
3. Better control of product distribution
1. Different reactions, such as ammonia oxidation, hydrogen and oxygen on platinum, aliphatic alcohol to aldehydes, and so on.
2. Biological applications, such as polymerase chain reaction (PCR), kinetics of bacterial reaction, T-sensor, and nuclei acid synthesis and detection.
Commercial use of
microreactors:
Microreactors are attracting more and more
interests, due to many important and unique features. However, the scale-up
problem must be overcome before the commercial use. Numbering-up of
microreactors should be about to lead to a cost-effective production of amounts
of chemicals not profitable on a larger scale. It is believed that
microreactors will become commercial in the near future.