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Slurry Reactor

What is a slurry reactor?

A slurry reactor is a particular continuous flow reactor which has the capability to mix solids, liquids and gases simultaneously. The solid, also referred to as the catalyst, is typically suspended in a liquid with gas pumped through it.


The ‘slurry’ is what is referred to as the suspended solid, whereby fine solid particles are suspended in a liquid to catalyse the reaction of a gas with a liquid.  A slurry reactor allows for all three phases to occur continuously in a reactor system.


What is an example of a slurry reactor?

Slurry reactors have a wide number of uses within the fine chemical and pharmaceutical industries. In order for flow reactors to replace the majority of batch reactor usage, they must have the capability to handle reactions that involve suspended solids.


Examples include heterogenous chemistry that involves solid slurries, such as hydrogenations, oxidations, chlorinations and reductions. This also includes reductions with metal catalysts and reactions that form a precipitate.


















Continuous flow slurry reactor


In a continuous flow reactor, solid particles which are part of the chemical process need to be able to flow through the system without risking blocking, bridging, fouling or settling. Standard flow methods used for handling homogenous fluid rarely work well when solids are present in the reactor.


The way the flow reactor is designed is integral to it functioning as a slurry reactor. This is why a continuous slurry reactor is usually engineered to have simple internal geometry and large channel diameters, which lead to good mixing.


Good mixing is required to keep solids suspended in horizontal transfer lines, with turbulent flow assisting in keeping the slurry at high axial velocity.


The versatility of the Coflore ACR cell block is a clear example of why a flow reactor is an ideal host for slurry reactions. With various injection sites available for the gas to be pumped in, in-between the various CSTR agitator stages, meaning the Coflore systems can be modelled to exact reaction requirements. 

The Coflore range, including the Coflore ACR and ATR have been engineered to accommodate a wide range of slurries with different attributes, including fast-settling solid slurries, slow-settling slurries and varying solid particle sizes.


Check out some of the technical notes and publications our systems have been involved in, including a phosphorylation reaction and deoxygenation.

A suspended solid slurry

slurry reactor technical note
slurry reactor technical note

Flow chemistry in pharmaceuticals: Slurry hydrogenation


Using Coflore’s answer to the slurry reactor, we recently tested our flow reactor for another pharmaceutical application. Slurry reactors are a fundamental

Related Pages...

Plug flow reactors

Useful External Links

Flow Chemistry (

“One of today's most important tools for modernizing the pharmaceutical industry is a process known as continuous manufacturing”

Director of the FDA’s Center for Drug Evaluation and Research, Janet Woodcock M.D.

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